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Fernando PMS, Hooper AJ, Burnett JR. Lepodisiran, an siRNA targeting lipoprotein(a) for the potential future treatment of cardiovascular disease. Expert Opin Investig Drugs 2024. [PMID: 38699928 DOI: 10.1080/13543784.2024.2352129] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2024] [Accepted: 05/02/2024] [Indexed: 05/05/2024]
Affiliation(s)
- P Mihika S Fernando
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital & Fiona Stanley Hospital Network, Perth, Western, Australia
| | - Amanda J Hooper
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital & Fiona Stanley Hospital Network, Perth, Western, Australia
- School of Medicine, University of Western Australia, Perth, Western, Australia
| | - John R Burnett
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital & Fiona Stanley Hospital Network, Perth, Western, Australia
- School of Medicine, University of Western Australia, Perth, Western, Australia
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Burnett JR. Pathology: evolution not revolution. Pathology 2024; 56:298-299. [PMID: 38355341 DOI: 10.1016/j.pathol.2024.01.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2024] [Accepted: 01/28/2024] [Indexed: 02/16/2024]
Affiliation(s)
- John R Burnett
- Editor-in-Chief, Pathology, Royal College of Pathologists of Australasia, Sydney, NSW, Australia; Department of Clinical Biochemistry, Royal Perth Hospital and Fiona Stanley Hospital Network, PathWest Laboratory Medicine WA, Perth, WA, Australia; School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, WA, Australia.
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Hooper AJ, Fernando PMS, Burnett JR. Potential of muvalaplin as a lipoprotein(a) inhibitor. Expert Opin Investig Drugs 2024; 33:5-7. [PMID: 38186354 DOI: 10.1080/13543784.2024.2302592] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Accepted: 01/03/2024] [Indexed: 01/09/2024]
Affiliation(s)
- Amanda J Hooper
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital & Fiona Stanley Hospital Network, Perth, Western Australia, Australia
- School of Medicine, University of Western Australia, Perth, Western Australia, Australia
| | - P Mihika S Fernando
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital & Fiona Stanley Hospital Network, Perth, Western Australia, Australia
| | - John R Burnett
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital & Fiona Stanley Hospital Network, Perth, Western Australia, Australia
- School of Medicine, University of Western Australia, Perth, Western Australia, Australia
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Loh WJ, Pang J, Chakraborty A, Ward NC, Chan DC, Hooper AJ, Bell DA, Burnett JR, Martin AC, Watts GF. Cascade testing of children and adolescents for elevated Lp(a) in pedigrees with familial hypercholesterolaemia. J Clin Lipidol 2024; 18:e33-e37. [PMID: 38040538 DOI: 10.1016/j.jacl.2023.11.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2023] [Accepted: 11/09/2023] [Indexed: 12/03/2023]
Abstract
Elevated plasma lipoprotein(a) [Lp(a)] is a common, inherited condition independently causing cardiovascular disease. Recent expert recommendations suggest opportunistically testing for elevated Lp(a) during cascade testing for familial hypercholesterolaemia (FH). We investigated the effectiveness of detecting elevated Lp(a) in 103 children and adolescents who were first-degree relatives of 66 adult index FH cases as part of an established FH cascade screening program. The yield of detection of elevated Lp(a) using a threshold of ≥30 mg/dL in children and adolescents was assessed. Cascade testing from FH index cases with elevated Lp(a) ≥50 mg/dL identified 1 case of Lp(a) ≥30 mg/dL for every 2 children or adolescents tested. In contrast, opportunistic screening from index cases with FH but normal Lp(a) levels demonstrated 1 case of Lp(a) ≥30 mg/dL for every 7.5 children or adolescents tested (p < 0.001). In conclusion, cascade testing for elevated Lp(a) from index cases with FH and elevated Lp(a) is effective in identifying new cases of elevated Lp(a).
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Affiliation(s)
- Wann Jia Loh
- School of Medicine, University of Western Australia, Perth, Australia (Drs Loh, Pang, Chakraborty, Chan, Hooper, Bell, Burnett, Watts); Department of Endocrinology, Changi General Hospital, Singapore (Dr Loh); Duke-NUS Medical School, Singapore (Dr Loh).
| | - Jing Pang
- School of Medicine, University of Western Australia, Perth, Australia (Drs Loh, Pang, Chakraborty, Chan, Hooper, Bell, Burnett, Watts)
| | - Anindita Chakraborty
- School of Medicine, University of Western Australia, Perth, Australia (Drs Loh, Pang, Chakraborty, Chan, Hooper, Bell, Burnett, Watts)
| | - Natalie C Ward
- Dobney Hypertension Centre, Medical School, University of Western Australia (Dr Ward)
| | - Dick C Chan
- School of Medicine, University of Western Australia, Perth, Australia (Drs Loh, Pang, Chakraborty, Chan, Hooper, Bell, Burnett, Watts)
| | - Amanda J Hooper
- School of Medicine, University of Western Australia, Perth, Australia (Drs Loh, Pang, Chakraborty, Chan, Hooper, Bell, Burnett, Watts); Department of Biochemistry, Royal Perth Hospital and Fiona Stanley Hospital Network, Pathwest Laboratory Medicine, Perth, Australia (Drs Hooper, Bell)
| | - Damon A Bell
- School of Medicine, University of Western Australia, Perth, Australia (Drs Loh, Pang, Chakraborty, Chan, Hooper, Bell, Burnett, Watts); Department of Biochemistry, Royal Perth Hospital and Fiona Stanley Hospital Network, Pathwest Laboratory Medicine, Perth, Australia (Drs Hooper, Bell); Department of Cardiology and Internal Medicine, Royal Perth Hospital, Perth, Australia (Drs Bell, Burnett, Watts)
| | - John R Burnett
- School of Medicine, University of Western Australia, Perth, Australia (Drs Loh, Pang, Chakraborty, Chan, Hooper, Bell, Burnett, Watts); Department of Cardiology and Internal Medicine, Royal Perth Hospital, Perth, Australia (Drs Bell, Burnett, Watts)
| | - Andrew C Martin
- School of Paediatrics and Child Health, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia (Dr Martin); Department of General Paediatrics, Perth Children's Hospital, Perth, Western Australia, Australia (Dr Martin)
| | - Gerald F Watts
- School of Medicine, University of Western Australia, Perth, Australia (Drs Loh, Pang, Chakraborty, Chan, Hooper, Bell, Burnett, Watts); Department of Cardiology and Internal Medicine, Royal Perth Hospital, Perth, Australia (Drs Bell, Burnett, Watts)
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Masuda R, Wist J, Lodge S, Kimhofer T, Hunter M, Hui J, Beilby JP, Burnett JR, Dwivedi G, Schlaich MP, Bong SH, Loo RL, Holmes E, Nicholson JK, Yeap BB. Plasma lipoprotein subclass variation in middle-aged and older adults: Sex-stratified distributions and associations with health status and cardiometabolic risk factors. J Clin Lipidol 2023; 17:677-687. [PMID: 37442713 DOI: 10.1016/j.jacl.2023.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 06/19/2023] [Accepted: 06/26/2023] [Indexed: 07/15/2023]
Abstract
BACKGROUND Circulating lipids and lipoproteins mediate cardiovascular risk, however routine plasma lipid biochemistry provides limited information on pro-atherogenic remnant particles. OBJECTIVE We analysed plasma lipoprotein subclasses including very low-density and intermediate-density lipoprotein (VLDL and IDL); and assessed their associations with health and cardiometabolic risk. METHODS From 1,976 community-dwelling adults aged 45-67 years, 114/1071 women (10.6%) and 153/905 men (16.9%) were categorised as very healthy. Fasting plasma lipoprotein profiles comprising 112 parameters were measured using 1H nuclear magnetic resonance (NMR) spectroscopy, and associations with health status and cardiometabolic risk factors examined. RESULTS HDL cholesterol was higher, and IDL and VLDL cholesterol and triglycerides lower, in very healthy women compared to other women, and women compared to men. IDL and VLDL cholesterol and triglyceride were lower in very healthy men compared to other men. HDL cholesterol and apolipoprotein (apo) A-I were inversely, and IDL and VLDL cholesterol, apoB-100, and apoB-100/apoA-I ratio directly associated with body mass index (BMI) in women and men. In women, LDL, IDL and VLDL cholesterol increased with age. Women with diabetes and cardiovascular disease had higher cholesterol, triglycerides, phospholipids and free cholesterol across IDL and VLDL fractions, with similar trends for men with diabetes. CONCLUSION Lipoprotein subclasses and density fractions, and their lipid and apolipoprotein constituents, are differentially distributed by sex, health status and BMI. Very healthy women and men are distinguished by favorable lipoprotein profiles, particularly lower concentrations of VLDL and IDL, providing reference intervals for comparison with general populations and adults with cardiometabolic risk factors.
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Affiliation(s)
- Reika Masuda
- Australian National Phenome Centre, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia
| | - Julien Wist
- Australian National Phenome Centre, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia; Center for Computational and Systems Medicine, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia; Chemistry Department, Universidad del Valle, 76001, Cali, Colombia
| | - Samantha Lodge
- Australian National Phenome Centre, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia; Center for Computational and Systems Medicine, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia
| | - Torben Kimhofer
- Australian National Phenome Centre, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia; Center for Computational and Systems Medicine, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia
| | - Michael Hunter
- School of Population and Global Health, University of Western Australia, Perth, WA, 6009, Australia
| | - Jennie Hui
- PathWest Laboratory Medicine, Queen Elizabeth II Medical Centre, Perth, WA, 6009, Australia
| | - John P Beilby
- School of Biomedical Sciences, University of Western Australia, Perth, WA, 6009, Australia
| | - John R Burnett
- Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth Hospital & Fiona Stanley Hospital Network, Perth, WA, 6000, Australia; Medical School, University of Western Australia, Perth, WA, 6009, Australia
| | - Girish Dwivedi
- Medical School, University of Western Australia, Perth, WA, 6009, Australia; Harry Perkins Institute of Medical Research, Perth, WA, 6150, Australia; Department of Cardiology, Fiona Stanley Hospital, Perth, WA, 6150, Australia
| | - Markus P Schlaich
- Medical School, University of Western Australia, Perth, WA, 6009, Australia; Dobney Hypertension Centre, Royal Perth Hospital Medical Research Foundation, University of Western Australia, Perth, WA, 6000, Australia; Departments of Cardiology and Nephrology, Royal Perth Hospital, Perth, WA, 6000, Australia
| | - Sze-How Bong
- Australian National Phenome Centre, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia; Center for Computational and Systems Medicine, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia
| | - Ruey Leng Loo
- Australian National Phenome Centre, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia; Center for Computational and Systems Medicine, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia
| | - Elaine Holmes
- Australian National Phenome Centre, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia; Center for Computational and Systems Medicine, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia; Department of Metabolism, Digestion and Reproduction, Faculty of Medicine, Imperial College London, London SW7 2AZ, United Kingdom
| | - Jeremy K Nicholson
- Australian National Phenome Centre, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia; Center for Computational and Systems Medicine, Health Futures Institute, Murdoch University, Perth, WA, 6150, Australia; Medical School, University of Western Australia, Perth, WA, 6009, Australia; Institute of Global Health Innovation, Imperial College London, London SW7 2AZ, United Kingdom.
| | - Bu B Yeap
- Medical School, University of Western Australia, Perth, WA, 6009, Australia; Department of Endocrinology and Diabetes, Fiona Stanley Hospital, Perth WA, 6150, Australia.
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Abstract
INTRODUCTION Atherosclerotic cardiovascular disease (ASCVD) is a leading cause of morbidity and mortality worldwide. Lowering LDL-cholesterol, by lifestyle modification or therapeutically, reduces the risk of ASCVD. Proprotein convertase subtilisin/kexin type 9 (PCSK9), a protein which binds to the LDL-receptor and induces degradation, is a clinically validated target to lower LDL-cholesterol. Injectable PCSK9 inhibitor therapies have demonstrated substantial reductions in LDL-cholesterol with associated decreased risk of ASCVD events. AREAS COVERED MK-0616 is an orally bioavailable, renally excreted, macrocyclic peptide inhibitor of PCSK9. The article provides an understanding of the chemistry and development, pharmacokinetic and pharmacodynamic characteristics of MK-0616 and insight into its clinical efficacy and safety. In clinical trials, MK-0616 produced dose-dependent reductions in LDL-cholesterol, non-HDL-cholesterol, and apolipoprotein (apo) B levels. Furthermore, MK-0616 modestly lowered lipoprotein (a) [Lp(a)]. EXPERT OPINION MK-0616 is a potent, oral macrocyclic peptide inhibitor of PCSK9 that is not only able to reduce LDL-cholesterol, non-HDL-cholesterol, and apoB, but can also lower Lp(a). Safety and tolerability studies reported to date are promising. MK-0616 may offer advantages over injectable anti-PCSK9 therapies in terms of ease of dosing, patient preference and cost. The results from phase III trials of MK-0616 on cardiovascular outcomes are awaited with interest.
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Affiliation(s)
- John R Burnett
- Department of Clinical Biochemistry, PathWest Laboratory Medicine, Perth, Western Australia
- Royal Perth Hospital & Fiona Stanley Hospital Network, Perth, Western Australia
| | - Amanda J Hooper
- Department of Clinical Biochemistry, PathWest Laboratory Medicine, Perth, Western Australia
- School of Medicine, University of Western Australia, Perth, Western Australia
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Page MM, Ellis KL, Chan DC, Pang J, Hooper AJ, Bell DA, Burnett JR, Moses EK, Watts GF. A variant in the fibronectin (FN1) gene, rs1250229-T, is associated with decreased risk of coronary artery disease in familial hypercholesterolaemia. J Clin Lipidol 2022; 16:525-529. [DOI: 10.1016/j.jacl.2022.05.065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Revised: 05/09/2022] [Accepted: 05/16/2022] [Indexed: 11/29/2022]
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Martin AC, Hooper AJ, Norman R, Nguyen LT, Burnett JR, Bell DA, Brett T, Garton-Smith J, Pang J, Nowak KJ, Watts GF. Pilot study of universal screening of children and child-parent cascade testing for familial hypercholesterolaemia in Australia. J Paediatr Child Health 2022; 58:281-287. [PMID: 34387892 DOI: 10.1111/jpc.15700] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 07/21/2021] [Accepted: 08/01/2021] [Indexed: 12/26/2022]
Abstract
AIM Familial hypercholesterolaemia (FH) is a common and treatable cause of premature coronary artery disease. However, the majority of individuals with FH remain undiagnosed. This study investigated the feasibility, acceptability and cost-effectiveness of screening children aged 1-2 years for FH at the time of an immunisation. METHODS Children 1-2 years of age were offered screening for FH with a point-of-care total cholesterol (TC) test by capillary-collected blood sample at the time of an immunisation. An additional blood sample was taken to allow genetic testing if the TC level was above the 95th percentile (>5.3 mmol/L). Parents of children diagnosed with FH were offered testing. Following detection of the affected parent, cascade testing of their first-degree blood relatives was performed. RESULTS We screened 448 children with 32 (7.1%) having a TC ≥ 5.3 mmol/L. The FH diagnosis was confirmed in three children (1:150 screened). Reverse cascade testing of other family members identified a further five individuals with FH; hence, eight new cases of FH were diagnosed from screening 448 children (1:56 screened). Ninety-six percent of parents would screen future children for FH. The approach was cost-effective, at $3979 per quality-adjusted life year gained. CONCLUSION In Western Australia, universal screening of children aged 1-2 years for FH, undertaken at the time of an immunisation, was a feasible and effective approach to detect children, parents and other blood relatives with FH. The approach was acceptable to parents and is potentially a highly cost-effective detection strategy for families at risk of FH.
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Affiliation(s)
- Andrew C Martin
- Department of General Paediatrics, Perth Children's Hospital, Perth, Western Australia, Australia.,School of Medicine, University of Western Australia, Perth, Western Australia, Australia
| | - Amanda J Hooper
- School of Medicine, University of Western Australia, Perth, Western Australia, Australia.,Department of Clinical Biochemistry, PathWest Laboratory Medicine, Perth, Western Australia, Australia
| | - Richard Norman
- School of Public Health, Curtin University, Perth, Western Australia, Australia
| | - Lan T Nguyen
- Department of Clinical Biochemistry, PathWest Laboratory Medicine, Perth, Western Australia, Australia
| | - John R Burnett
- School of Medicine, University of Western Australia, Perth, Western Australia, Australia.,Department of Clinical Biochemistry, PathWest Laboratory Medicine, Perth, Western Australia, Australia.,Lipid Disorders Clinic, Cardiometabolic Service, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Damon A Bell
- School of Medicine, University of Western Australia, Perth, Western Australia, Australia.,Department of Clinical Biochemistry, PathWest Laboratory Medicine, Perth, Western Australia, Australia.,Lipid Disorders Clinic, Cardiometabolic Service, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Tom Brett
- General Practice and Primary Health Care Research, School of Medicine, University of Notre Dame, Fremantle, Western Australia, Australia
| | - Jacquie Garton-Smith
- Clinical Excellence Division, Department of Health, Health Networks, Perth, Western Australia, Australia
| | - Jing Pang
- School of Medicine, University of Western Australia, Perth, Western Australia, Australia
| | - Kristen J Nowak
- Public and Aboriginal Health Division, Department of Health, Office of Population Health Genomics, Perth, Western Australia, Australia
| | - Gerald F Watts
- School of Medicine, University of Western Australia, Perth, Western Australia, Australia.,Lipid Disorders Clinic, Cardiometabolic Service, Royal Perth Hospital, Perth, Western Australia, Australia
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Thowfeek Zeenath Thaneefa M, Amarakoon G, Mendis D, Jasinge E, Hooper AJ, Burnett JR. Incidental diagnosis of LPL deficiency in an infant presenting with an acute respiratory infection. Clin Chim Acta 2022; 529:1-3. [DOI: 10.1016/j.cca.2022.01.016] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Revised: 01/18/2022] [Accepted: 01/21/2022] [Indexed: 11/27/2022]
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Chakraborty A, Pang J, Chan DC, Ellis KL, Hooper AJ, Bell DA, Burnett JR, Moses EK, Watts GF. Cascade testing for elevated lipoprotein(a) in relatives of probands with familial hypercholesterolaemia and elevated lipoprotein(a). Atherosclerosis 2021; 349:219-226. [PMID: 34862044 DOI: 10.1016/j.atherosclerosis.2021.11.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Revised: 10/08/2021] [Accepted: 11/03/2021] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND AIMS Familial hypercholesterolaemia (FH) and elevated plasma lipoprotein(a) [Lp(a)] are inherited conditions independently associated with atherosclerotic cardiovascular disease. This study investigated the detection of new cases of elevated Lp(a) during cascade testing of relatives of probands with a definite diagnosis of FH and elevated Lp(a) (≥50 mg/dL). METHODS Relatives from 62 adult probands were tested for FH genetically and for elevated Lp(a) using an immunoassay. The prevalence and yield of new cases of FH with or without elevated Lp(a) among relatives and the association between the detection of elevated Lp(a) and the Lp(a) concentration of the probands were assessed. RESULTS Among 162 relatives tested (136 adults and 26 children), the prevalence of FH and elevated Lp(a) was 60.5% and 41.4%, respectively: FH alone was detected in 31.5%, elevated Lp(a) alone in 12.3%, FH with elevated Lp(a) in 29.0%, and neither disorder in 27.2% of the relatives. Cascade testing detected a new case of FH, elevated Lp(a) and FH with elevated Lp(a) for every 1.5, 2.1 and 3.0 relatives tested, respectively. The proportion of relatives detected with elevated Lp(a) was significantly higher when tested from probands with Lp(a) ≥100 mg/dL compared with those from probands with Lp(a) between 50 and 99 mg/dL (53% vs 34%, p = 0.018). The concordance between the detection of FH and elevated Lp(a) was 56.2% (kappa statistic 0.154), indicating a poor agreement. CONCLUSIONS A dual approach to cascade testing families for FH and high Lp(a) from appropriate probands can effectively identify not only new cases of FH, but also new cases of elevated Lp(a) with or without FH. The findings accord with the co-dominant and independent heritability of FH and Lp(a).
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Affiliation(s)
- Anindita Chakraborty
- Medical School, University of Western Australia, Perth, Western Australia, Australia
| | - Jing Pang
- Medical School, University of Western Australia, Perth, Western Australia, Australia
| | - Dick C Chan
- Medical School, University of Western Australia, Perth, Western Australia, Australia
| | - Katrina L Ellis
- Medical School, University of Western Australia, Perth, Western Australia, Australia
| | - Amanda J Hooper
- Medical School, University of Western Australia, Perth, Western Australia, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia
| | - Damon A Bell
- Medical School, University of Western Australia, Perth, Western Australia, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia; Lipid Disorders Clinic, Department of Cardiology and Internal Medicine, Royal Perth Hospital, Perth, Western Australia, Australia
| | - John R Burnett
- Medical School, University of Western Australia, Perth, Western Australia, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia; Lipid Disorders Clinic, Department of Cardiology and Internal Medicine, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Eric K Moses
- Menzies Institute for Medical Research, University of Tasmania, Tasmania, Australia
| | - Gerald F Watts
- Medical School, University of Western Australia, Perth, Western Australia, Australia; Lipid Disorders Clinic, Department of Cardiology and Internal Medicine, Royal Perth Hospital, Perth, Western Australia, Australia.
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Burnett JR. Genetic testing for familial hypercholesterolaemia. Pathology 2021. [DOI: 10.1016/j.pathol.2021.05.042] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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12
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Burnett JR. Genetic testing for familial hypercholesterolaemia. Pathology 2021. [DOI: 10.1016/j.pathol.2021.05.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Heenan JM, Hooper AJ, Burnett JR, Cooney J. l-asparaginase-induced biochemical toxicities in young adults with acute lymphoblastic leukaemia and T-lymphoblastic lymphoma. Pathology 2021; 53:924-926. [PMID: 34049714 DOI: 10.1016/j.pathol.2021.02.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 02/11/2021] [Accepted: 02/16/2021] [Indexed: 01/19/2023]
Affiliation(s)
- Jessica M Heenan
- Department of Haematology, Launceston General Hospital, Launceston, Tas, Australia
| | - Amanda J Hooper
- Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, WA, Australia; School of Medicine, University of Western Australia, Nedlands, WA, Australia
| | - John R Burnett
- Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, WA, Australia; School of Medicine, University of Western Australia, Nedlands, WA, Australia
| | - Julian Cooney
- Department of Haematology, PathWest Laboratory Medicine, Fiona Stanley Hospital, Perth, WA, Australia.
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Thadchanamoorthy V, Dayasiri K, Majitha SI, Hooper AJ, Burnett JR. Homozygous autosomal recessive hypercholesterolaemia in a South Asian child presenting with multiple cutaneous xanthomata. Ann Clin Biochem 2021; 58:153-156. [PMID: 32936664 DOI: 10.1177/0004563220961755] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Autosomal recessive hypercholesterolemia (ARH; OMIM #603813) is an extremely rare disorder of lipid metabolism caused by loss-of-function variants in the LDL receptor adapter protein 1 (LDLRAP1) gene, which is characterized by severe hypercholesterolaemia and an increased risk of premature atherosclerotic cardiovascular disease. We report the case of an 11-year-old girl who presented with multiple painless yellowish papules around her elbows and knees of two-year duration. She had been reviewed by several general practitioners, with some of the papules having been excised, but without a specific diagnosis being made. The child was referred to a paediatric service for further evaluation and treatment of the cutaneous lesions, which appeared xanthomatous in nature. A lipid profile showed severe hypercholesterolaemia. Next generation sequencing analysis of a monogenic hypercholesterolaemia gene panel revealed homozygosity for a pathogenic frameshift mutation, c.71dupG, p.Gly25Argfs*9 in LDLRAP1. Her parents and brother, who were asymptomatic, were screened and found to be heterozygous carriers of the LDLRAP1 variant. There was no known consanguinity in the family. She was commenced on the HMG-CoA reductase inhibitor, atorvastatin, to good effect, with a ∼76% reduction in LDL-cholesterol at a dose of 50 mg per day. At six-month follow-up, there had been no obvious regression of the xanthomata, but importantly, no enlargement of, or the development of new papular lesions, have occurred. In summary, we report a child who presented with multiple cutaneous xanthomata and was confirmed to have ARH by the presence of a homozygous novel pathogenic frameshift variant in LDLRAP1.
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Affiliation(s)
- V Thadchanamoorthy
- Department of Paediatrics, Faculty of Health Care Science, Eastern University, Chenkalady, Sri Lanka
| | | | - S I Majitha
- Department of Chemical Pathology, Batticaloa Teaching Hospital, Batticaloa, Sri Lanka
| | - Amanda J Hooper
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Australia
- School of Medicine, University of Western Australia, Royal Perth Hospital, Perth, Australia
| | - John R Burnett
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Australia
- School of Medicine, University of Western Australia, Royal Perth Hospital, Perth, Australia
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15
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Burnett JR, Hooper AJ, Hegele RA. Remnant Cholesterol and Atherosclerotic Cardiovascular Disease Risk. J Am Coll Cardiol 2020; 76:2736-2739. [DOI: 10.1016/j.jacc.2020.10.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2020] [Accepted: 10/19/2020] [Indexed: 12/22/2022]
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Page MM, Ekinci EI, Burnett JR, Hooper AJ, Reid N, Bishop W, Florkowski CM, Scott R, O'Brien RC, Watts GF. Lipoprotein apheresis and PCSK9 inhibitors for severe familial hypercholesterolaemia: Experience from Australia and New Zealand. J Clin Apher 2020; 36:48-58. [PMID: 32911577 DOI: 10.1002/jca.21839] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Revised: 08/14/2020] [Accepted: 08/17/2020] [Indexed: 12/23/2022]
Abstract
INTRODUCTION Severe familial hypercholesterolaemia (FH) causes premature disability and death due to atherosclerotic cardiovascular disease and is refractory to standard lipid-lowering therapies. Lipoprotein apheresis (LA) has long been a standard of care for patients with severe FH, but is invasive, expensive and time-consuming for patients and their caregivers. Newer drug therapies, including the proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors, may reduce the need for LA. MATERIALS AND METHODS We audited the records of 16 patients (eight homozygous, eight heterozygous) treated with LA in Australia and New Zealand, 14 of whom subsequently commenced PCSK9 inhibitor therapy. LA was performed by cascade filtration in all centres. RESULTS LDL-cholesterol was acutely lowered by 69 ± 7% in patients with homozygous FH and by 72 ± 9% in those with heterozygous FH, representing time-averaged reductions of 36 ± 12% and 34 ± 5%, respectively. LA was well-tolerated, and patients reported comparable quality of life to population and disease-related norms. After commencement of PCSK9 inhibitors, four of seven patients with homozygous FH had meaningful biochemical responses, with a reduction in the frequency of LA permitted in one patient and complete cessation in another. Four of seven patients with heterozygous FH were able to be managed without LA after commencing PCSK9 inhibitors. CONCLUSION While PCSK9 inhibitors have reduced the need for LA, some patients with severe FH continue to require LA, and will require it for the foreseeable future. However, emerging therapies, including angiopoetin-like 3 inhibitors, may further reduce the need for LA.
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Affiliation(s)
- Michael M Page
- School of Medicine, University of Western Australia, Crawley, Western Australia, Australia.,Western Diagnostic Pathology, Myaree, Western Australia, Australia
| | - Elif I Ekinci
- Department of Endocrinology, Austin Health, Heidelberg, Victoria, Australia.,Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
| | - John R Burnett
- School of Medicine, University of Western Australia, Crawley, Western Australia, Australia.,Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital, Perth, Western Australia, Australia.,Lipid Disorders Clinic, Cardiovascular Medicine, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Amanda J Hooper
- School of Medicine, University of Western Australia, Crawley, Western Australia, Australia.,Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital, Perth, Western Australia, Australia
| | - Nicola Reid
- Cardiovascular Prevention and Lipid Disorders Clinic, Christchurch Hospital, Christchurch, New Zealand
| | - Warrick Bishop
- Calvary Cardiac Centre, Calvary Hospital, Lenah Valley, Tasmania, Australia
| | - Chris M Florkowski
- Cardiovascular Prevention and Lipid Disorders Clinic, Christchurch Hospital, Christchurch, New Zealand.,Canterbury Health Laboratories, Christchurch, New Zealand
| | - Russell Scott
- Cardiovascular Prevention and Lipid Disorders Clinic, Christchurch Hospital, Christchurch, New Zealand
| | - Richard C O'Brien
- Department of Endocrinology, Austin Health, Heidelberg, Victoria, Australia.,Department of Medicine, Austin Health, University of Melbourne, Heidelberg, Victoria, Australia
| | - Gerald F Watts
- School of Medicine, University of Western Australia, Crawley, Western Australia, Australia.,Lipid Disorders Clinic, Cardiovascular Medicine, Royal Perth Hospital, Perth, Western Australia, Australia
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Pang J, Sullivan DR, Hare DL, Colquhoun DM, Bates TR, Ryan JDM, Bishop W, Burnett JR, Bell DA, Simons LA, Mirzaee S, Kostner KM, Nestel PJ, Wilson AM, O'Brien RC, Janus ED, Clifton PM, Ardill JJ, Chan DC, van Bockxmeer F, Watts GF. Gaps in the Care of Familial Hypercholesterolaemia in Australia: First Report From the National Registry. Heart Lung Circ 2020; 30:372-379. [PMID: 32873489 DOI: 10.1016/j.hlc.2020.07.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2020] [Revised: 06/26/2020] [Accepted: 07/08/2020] [Indexed: 12/14/2022]
Abstract
BACKGROUND Familial hypercholesterolaemia (FH) is under-diagnosed and under-treated worldwide, including Australia. National registries play a key role in identifying patients with FH, understanding gaps in care and advancing the science of FH to improve care for these patients. METHODS The FH Australasia Network has established a national web-based registry to raise awareness of the condition, facilitate service planning and inform best practice and care services in Australia. We conducted a cross-sectional analysis of 1,528 FH adults enrolled in the registry from 28 lipid clinics. RESULTS The mean age at enrolment was 53.4±15.1 years, 50.5% were male and 54.3% had undergone FH genetic testing, of which 61.8% had a pathogenic FH-causing gene variant. Only 14.0% of the cohort were family members identified through cascade testing. Coronary artery disease (CAD) was reported in 28.0% of patients (age of onset 49.0±10.5 years) and 64.9% had at least one modifiable cardiovascular risk factor. The mean untreated LDL-cholesterol was 7.4±2.5 mmol/L. 80.8% of patients were on lipid-lowering therapy with a mean treated LDL-cholesterol of 3.3±1.7 mmol/L. Among patients receiving lipid-lowering therapies, 25.6% achieved an LDL-cholesterol target of <2.5 mmol/L without CAD or <1.8 mmol/L with CAD. CONCLUSION Patients in the national FH registry are detected later in life, have a high burden of CAD and risk factors, and do not achieve guideline-recommended LDL-cholesterol targets. Genetic and cascade testing are under-utilised. These deficiencies in care need to be addressed as a public health priority.
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Affiliation(s)
- Jing Pang
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, WA, Australia
| | - David R Sullivan
- Department of Chemical Pathology, Royal Prince Alfred Hospital, Sydney, NSW, Australia; Sydney Medical School, University of Sydney, Sydney, NSW, Australia
| | - David L Hare
- Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, Vic, Australia; Department of Cardiology, Austin Health, Melbourne, Vic, Australia
| | - David M Colquhoun
- School of Medicine, University of Queensland, Brisbane, Qld, Australia; Wesley Medical Centre, Wesley Hospital and Greenslopes Private Hospital, Brisbane, Qld, Australia
| | - Timothy R Bates
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, WA, Australia; Department of Medicine, St John of God Hospital Midland, Perth, WA, Australia; Curtin Medical School, Faculty of Health Sciences, Curtin University, Perth, WA, Australia
| | | | - Warrick Bishop
- Department of Cardiology, Calvary Cardiac Centre, Calvary Health Care, Hobart, Tas, Australia
| | - John R Burnett
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, WA, Australia; Lipid Disorders Clinic, Cardiometabolic Services, Department of Cardiology, Royal Perth Hospital, Perth, WA, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, WA, Australia
| | - Damon A Bell
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, WA, Australia; Lipid Disorders Clinic, Cardiometabolic Services, Department of Cardiology, Royal Perth Hospital, Perth, WA, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, WA, Australia
| | - Leon A Simons
- University of New South Wales and St Vincent's Hospital, Sydney, NSW, Australia
| | - Sam Mirzaee
- Monash Cardiovascular Research Centre, MonashHeart, Melbourne, Vic, Australia
| | - Karam M Kostner
- Department of Cardiology, Mater Hospital, University of Queensland, Brisbane, Qld, Australia
| | - Paul J Nestel
- Baker Heart & Diabetes Institute, Melbourne, Vic, Australia; Department of Cardiology, The Alfred Hospital, Melbourne, Vic, Australia
| | - Andrew M Wilson
- Department of Cardiology, St. Vincent's Hospital, Melbourne, Vic, Australia; Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne, Vic, Australia
| | - Richard C O'Brien
- Austin Clinical School, University of Melbourne, Melbourne, Vic, Australia; Department of Endocrinology, Austin Health, Melbourne, Vic, Australia
| | - Edward D Janus
- Western Health Chronic Disease Alliance, Western Health, Melbourne, Vic, Australia; Department of Medicine, Western Health Melbourne Medical School, University of Melbourne, Melbourne, Vic, Australia
| | - Peter M Clifton
- Department of Endocrinology, Royal Adelaide Hospital, Adelaide, SA, Australia
| | | | - Dick C Chan
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, WA, Australia
| | - Frank van Bockxmeer
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, WA, Australia
| | - Gerald F Watts
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, WA, Australia; Department of Cardiology, Calvary Cardiac Centre, Calvary Health Care, Hobart, Tas, Australia.
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18
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Affiliation(s)
| | - Belinda Neill
- Editorial Manager, Pathology, RCPA, Sydney, NSW, Australia
| | - John R Burnett
- Senior Associate Editor Clinical Pathology, Pathology, RCPA, Sydney, NSW, Australia
| | - Richard A Scolyer
- Senior Associate Editor Anatomical Pathology, Pathology, RCPA, Sydney, NSW, Australia
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19
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Napier KR, Hooper AJ, Ng DM, Render L, Bell DA, Pang J, Watts GF, Bellgard MI, Burnett JR. Design, development and deployment of a web-based patient registry for rare genetic lipid disorders. Pathology 2020; 52:447-452. [PMID: 32276786 DOI: 10.1016/j.pathol.2020.02.002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2019] [Revised: 02/04/2020] [Accepted: 02/07/2020] [Indexed: 10/24/2022]
Abstract
Rare genetic lipid disorders comprise all the monogenic disorders of lipoprotein metabolism with the exception of heterozygous familial hypercholesterolaemia (FH). The creation and maintenance of patient registries is critical for disease monitoring, improving clinical best practice, facilitating research and enabling the development of novel therapeutics, but very few disease-specific rare genetic lipid disorder registries currently exist. Our aim was to design, develop and deploy a web-based patient registry for rare genetic lipid disorders. The Rare Genetic Lipid Disorders Registry is based on the FH Australasia Network (FHAN) Registry, which has been operating since 2015. The Rare Genetic Lipid Disorders Registry was deployed utilising the open-source Rare Disease Registry Framework (RDRF), which enables the efficient customisation and sustainable deployment of web-based registries. The Registry has been designed to capture longitudinal data on 13 rare genetic lipid disorders, with the ability to add more if required in the future. Recruitment of volunteers into the Registry is currently through the Royal Perth Hospital Lipid Disorders Clinic in Western Australia. Although in essence a clinic-based patient registry, the web-based design allows for expansion and distribution across Australia and beyond. Data collated by the Registry may ultimately improve the diagnosis, management and treatment of these conditions.
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Affiliation(s)
- Kathryn R Napier
- Centre for Comparative Genomics, Murdoch University, Murdoch, WA, Australia
| | - Amanda J Hooper
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, WA, Australia; School of Medicine, University of Western Australia, Nedlands, WA, Australia
| | - David M Ng
- School of Medicine, University of Western Australia, Nedlands, WA, Australia
| | - Lee Render
- Centre for Comparative Genomics, Murdoch University, Murdoch, WA, Australia
| | - Damon A Bell
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, WA, Australia; School of Medicine, University of Western Australia, Nedlands, WA, Australia; Lipid Disorders Clinic, Cardiometabolic Service, Royal Perth Hospital, Perth, WA, Australia
| | - Jing Pang
- School of Medicine, University of Western Australia, Nedlands, WA, Australia
| | - Gerald F Watts
- School of Medicine, University of Western Australia, Nedlands, WA, Australia; Lipid Disorders Clinic, Cardiometabolic Service, Royal Perth Hospital, Perth, WA, Australia
| | - Matthew I Bellgard
- eResearch Office, Queensland University of Technology, Brisbane, Qld, Australia
| | - John R Burnett
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, WA, Australia; School of Medicine, University of Western Australia, Nedlands, WA, Australia.
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20
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Abstract
PURPOSE OF REVIEW To appraise recent advances in our knowledge of the severe genetic HDL deficiency disorder, Tangier disease. RECENT FINDINGS While Tangier disease can cause premature atherosclerotic cardiovascular disease (ASCVD), new evidence suggests that heterozygous ABCA1 variant carriers are also at increased risk. Advances have been made in the study of the neurological abnormalities observed in Tangier disease, both in their assessment and the identification of potential new therapies. SUMMARY Tangier disease is an extremely rare condition and, as such, the published literature around its range of clinical manifestations, including peripheral neuropathy, premature ASCVD and platelet abnormalities is limited. Patient registries may assist in this regard.
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Affiliation(s)
- Amanda J Hooper
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital & Fiona Stanley Hospital Network
- School of Medicine, Faculty of Health & Medical Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Robert A Hegele
- Departments of Medicine and Biochemistry, Schulich School of Medicine and Robarts Research Institute, Western University, London, Ontario, Canada
| | - John R Burnett
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital & Fiona Stanley Hospital Network
- School of Medicine, Faculty of Health & Medical Sciences, University of Western Australia, Perth, Western Australia, Australia
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21
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Pang J, Abraham A, Vargas-García C, Bates TR, Chan DC, Hooper AJ, Bell DA, Burnett JR, Schultz CJ, Watts GF. An age-matched computed tomography angiographic study of coronary atherosclerotic plaques in patients with familial hypercholesterolaemia. Atherosclerosis 2020; 298:52-57. [PMID: 32171980 DOI: 10.1016/j.atherosclerosis.2020.03.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Revised: 02/28/2020] [Accepted: 03/03/2020] [Indexed: 12/12/2022]
Abstract
BACKGROUND AND AIMS Familial hypercholesterolaemia (FH) is characterised by a high, but variable risk of premature coronary artery disease (CAD). Cardiac computed tomography angiography (CCTA) can be employed to assess subclinical coronary atherosclerosis. We investigated the features and distribution of coronary artery plaques in asymptomatic patients with and without genetically confirmed heterozygous FH. METHODS We undertook an aged-matched case-control study of asymptomatic phenotypic FH patients with (cases, M+) and without (controls, M-) an FH-causing mutation. Coronary atherosclerosis was assessed by CCTA and calcium scoring. Coronary segments were evaluated for global and vessel-level coronary plaques and degree of stenosis. RESULTS We studied 104 cases and 104 controls (mean age 49.9 ± 10.4 years), who had a similar spectrum of non-cardiovascular risk factors. Pre-treatment plasma LDL-cholesterol was higher in the M+ than M- group (7.8 ± 2.1 vs 6.2 ± 1.2 mmol/L, p<0.001). There was a greater proportion of patients with mixed and calcified plaque, as well as a higher coronary artery calcium score and segment stenosis score (all p<0.05), in the M+ compared with the M- group. M+ patients also had a significantly higher frequency of coronary artery calcium in the left main and anterior descending and right coronary arteries (all p<0.05), but not in the left circumflex. CONCLUSIONS Among patients with phenotypic FH, those with a genetically confirmed diagnosis had a higher frequency and severity of coronary atherosclerotic plaques, and specifically more advanced calcified plaques.
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Affiliation(s)
- Jing Pang
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Arun Abraham
- Department of Diagnostic Imaging, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Cristian Vargas-García
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Timothy R Bates
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia; St John of God Midland Public and Private Hospitals, Midland, Western Australia, Australia; Curtin Medical School, Faculty of Health Sciences, Curtin University, Perth, Western Australia, Australia
| | - Dick C Chan
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Amanda J Hooper
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia
| | - Damon A Bell
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia; Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia
| | - John R Burnett
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia; Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Carl J Schultz
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia; Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Gerald F Watts
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia; Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia.
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22
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Ellis KL, Hooper AJ, Pang J, Chan DC, Burnett JR, Bell DA, Schultz CJ, Moses EK, Watts GF. A genetic risk score predicts coronary artery disease in familial hypercholesterolaemia: enhancing the precision of risk assessment. Clin Genet 2019; 97:257-263. [PMID: 31571196 DOI: 10.1111/cge.13648] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2019] [Revised: 08/31/2019] [Accepted: 09/07/2019] [Indexed: 01/31/2023]
Abstract
Familial hypercholesterolaemia (FH) is associated with increased risk of coronary artery disease (CAD); however, risk prediction and stratification remain a challenge. Genetic risk scores (GRS) may have utility in identifying FH patients at high CAD risk. The study included 811 patients attending the lipid disorders clinic at Royal Perth Hospital with mutation-positive (n = 251) and mutation-negative (n = 560) FH. Patients were genotyped for a GRS previously associated with CAD. Associations between the GRS, clinical characteristics, and CAD were assessed using regression analyses. The average age of patients was 49.6 years, and 44.1% were male. The GRS was associated with increased odds of a CAD event in mutation-positive [odds ratio (OR) = 3.3; 95% confidence interval (CI) = 1.3-8.2; P = .009] and mutation-negative FH patients (OR = 1.8; 95% CI = 1.0-3.3; P = .039) after adjusting for established predictors of CAD risk. The GRS was associated with greater subclinical atherosclerosis as assessed by coronary artery calcium score (P = .039). A high GRS was associated with CAD defined clinically and angiographically in FH patients. High GRS patients may benefit from more intensive management including lifestyle modification and aggressive lipid-lowering therapy. Further assessment of the utility of the GRS requires investigation in prospective cohorts, including its role in influencing the management of FH patients in the clinic.
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Affiliation(s)
- Katrina L Ellis
- Centre for Genetic Origins of Health and Disease, School of Biomedical Sciences, University of Western Australia, Perth, Western Australia, Australia.,Centre for Genetic Origins of Health and Disease, School of Biomedical Sciences, Curtin University, Perth, Western Australia, Australia.,School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Amanda J Hooper
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia.,Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia
| | - Jing Pang
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Dick C Chan
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - John R Burnett
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia.,Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia.,Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Damon A Bell
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia.,Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia.,Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Carl J Schultz
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia.,Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Eric K Moses
- Centre for Genetic Origins of Health and Disease, School of Biomedical Sciences, University of Western Australia, Perth, Western Australia, Australia.,Centre for Genetic Origins of Health and Disease, School of Biomedical Sciences, Curtin University, Perth, Western Australia, Australia
| | - Gerald F Watts
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia.,Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia
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23
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Chan DC, Pang J, Hooper AJ, Bell DA, Burnett JR, Watts GF. Effect of Lipoprotein(a) on the Diagnosis of Familial Hypercholesterolemia: Does It Make a Difference in the Clinic? Clin Chem 2019; 65:1258-1266. [DOI: 10.1373/clinchem.2019.306738] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Accepted: 06/10/2019] [Indexed: 11/06/2022]
Abstract
Abstract
BACKGROUND
Diagnostic tools for familial hypercholesterolemia (FH) rely on estimation of LDL cholesterol concentration. However, routine measurement or calculation of LDL cholesterol concentration using the Friedewald equation contains a cholesterol contribution from lipoprotein(a) [Lp(a)]. We investigated whether Lp(a) influences the phenotypic diagnosis of FH by commonly used clinical criteria.
METHODS
A cohort of 907 adult index patients attending a clinic were studied. The Dutch Lipid Clinic Network (DLCN) and Simon Broome (SB) diagnostic criteria were estimated before and after adjusting LDL cholesterol concentration for the cholesterol content (30%) of Lp(a). Diagnostic reclassification rates and area under the ROC (AUROC) curves in predicting an FH mutation were also compared.
RESULTS
Seventy-four patients defined by DLCN criteria (8.2%) and 207 patients defined by SB criteria (22.8%) were reclassified to “unlikely” FH after adjusting LDL cholesterol for Lp(a) cholesterol. The proportion of FH patients defined by DLCN (probable/definite) and SB (possible/definite) criteria decreased significantly in patients with increased Lp(a) (>0.5 g/L; n = 330) after Lp(a) cholesterol adjustment (P < 0.01). The overall reclassification rate was significantly higher in patients with Lp(a) concentration >1.0 g/L (P < 0.001). The AUROC curve for LDL cholesterol concentration ≥191 mg/dL (≥5.0 mmol/L), DLCN criteria, and SB criteria in predicting an FH mutation increased significantly after adjustment (P < 0.001). There was no significant difference in AUROC curve before and after Lp(a) cholesterol adjustment at an LDL cholesterol concentration ≥251 mg/dL (≥6.5 mmol/L).
CONCLUSIONS
Adjusting LDL cholesterol concentration for Lp(a) cholesterol improves the diagnostic accuracy of DLCN and SB criteria, especially with Lp(a) >1.0 g/L and LDL cholesterol <251 mg/dL (<6.5 mmol/L). Lp(a) should be measured in all patients suspected of having FH.
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Affiliation(s)
- Dick C Chan
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Jing Pang
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Amanda J Hooper
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia
| | - Damon A Bell
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia
- Lipid Disorders Clinic, Cardiometabolic Services, Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia
| | - John R Burnett
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia
- Lipid Disorders Clinic, Cardiometabolic Services, Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Gerald F Watts
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia
- Lipid Disorders Clinic, Cardiometabolic Services, Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia
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Napier KR, Hooper AJ, Ng DM, Render L, Bell DA, Pang J, Watts GF, Bellgard MI, Burnett JR. A web-based registry for rare genetic lipid disorders. Pathology 2019. [DOI: 10.1016/j.pathol.2018.12.302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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25
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Affiliation(s)
- John R Burnett
- Department of Clinical Biochemistry, Royal Perth Hospital and Fiona Stanley Hospital Network, PathWest Laboratory Medicine, Perth, WA, Australia; School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, WA, Australia.
| | - Amanda J Hooper
- Department of Clinical Biochemistry, Royal Perth Hospital and Fiona Stanley Hospital Network, PathWest Laboratory Medicine, Perth, WA, Australia; School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, WA, Australia
| | - Robert A Hegele
- Departments of Medicine and Biochemistry, Schulich School of Medicine and Robarts Research Institute, Western University, London, Ontario, Canada
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26
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Carr SS, Hooper AJ, Sullivan DR, Burnett JR. Non-HDL-cholesterol and apolipoprotein B compared with LDL-cholesterol in atherosclerotic cardiovascular disease risk assessment. Pathology 2018; 51:148-154. [PMID: 30595507 DOI: 10.1016/j.pathol.2018.11.006] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Revised: 11/25/2018] [Accepted: 11/25/2018] [Indexed: 12/11/2022]
Abstract
Low density lipoprotein (LDL) is the predominant atherogenic lipoprotein particle in the circulation. Conventionally, a fasting lipid profile has been used for atherosclerotic cardiovascular disease (ASCVD) risk assessment. A non-fasting sample is now regarded as a suitable alternative to a fasting sample. In routine clinical practice, the Friedewald equation is used to estimate LDL-cholesterol, but it has limitations. Commercially available direct measures of LDL-cholesterol are not standardised. LDL-cholesterol is a well-established risk factor for ASCVD, being the primary therapeutic target in both primary and secondary prevention. Non-high-density lipoprotein (HDL)-cholesterol is a measure of the cholesterol content in the atherogenic lipoproteins, but it does not reflect the particle number. Non-HDL-cholesterol has the advantage over LDL-cholesterol of including remnant cholesterol and being independent of triglyceride variability, but it is compromised by the non-specificity bias of direct HDL-cholesterol methods used in the calculation. Apolipoprotein (apo) B, the major structural protein in very low-density lipoprotein, intermediate density lipoprotein, LDL and lipoprotein (a), is a measure of the number of atherogenic lipoproteins. ApoB methods are standardised, but the assay comes at an additional, albeit relatively low cost. Non-HDL-cholesterol and apoB are more accurate measures than LDL-cholesterol in hypertriglyceridaemic individuals, non-fasting samples, and in those with very-low LDL-cholesterol concentrations. Accumulating evidence suggests that non-HDL-cholesterol and apoB are superior to LDL-cholesterol in predicting ASCVD risk, and both have been designated as secondary targets in some treatment guidelines. We review the measurement, potential role, utility and current status of non-HDL-cholesterol and apoB when compared with LDL-cholesterol in ASCVD risk assessment.
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Affiliation(s)
- Stuart S Carr
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, WA, Australia
| | - Amanda J Hooper
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, WA, Australia; Department of Clinical Biochemistry, Royal Perth Hospital and Fiona Stanley Hospital Network, PathWest Laboratory Medicine, Perth, WA, Australia
| | - David R Sullivan
- Department of Chemical Pathology, Royal Prince Alfred Hospital, Camperdown, NSW, Australia
| | - John R Burnett
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, WA, Australia; Department of Clinical Biochemistry, Royal Perth Hospital and Fiona Stanley Hospital Network, PathWest Laboratory Medicine, Perth, WA, Australia.
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Affiliation(s)
- John R Burnett
- From the School of Medicine, University of Western Australia, and the Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Australia
| | - Amanda J Hooper
- From the School of Medicine, University of Western Australia, and the Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Australia
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Pang J, Martin AC, Bates TR, Hooper AJ, Bell DA, Burnett JR, Norman R, Watts GF. Parent-child genetic testing for familial hypercholesterolaemia in an Australian context. J Paediatr Child Health 2018; 54:741-747. [PMID: 29626384 DOI: 10.1111/jpc.13898] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2017] [Revised: 12/18/2017] [Accepted: 01/14/2018] [Indexed: 01/18/2023]
Abstract
AIM The aim of this study was to evaluate the clinical outcome of parent-child testing for familial hypercholesterolaemia (FH) employing genetic testing and the likely additional cost of treating each child. METHODS Parent-child testing for gene variants causative of FH was carried out according to Australian guidelines. The number of new cases detected, the low-density lipoprotein (LDL)-cholesterol that best predicted a mutation and the proportional reduction in LDL-cholesterol following statin treatment was evaluated. Treatment costs were calculated as the cost per mmol/L reduction in LDL-cholesterol. RESULTS A total of 126 adult patients, known to have a pathogenic mutation causative of FH, and their children were studied. From 244 children identified, 148 (60.7%) were genetically screened; 84 children were identified as mutative positive (M+) and 64 as mutative negative. Six of the M+ children were already on statin treatment; 40 were subsequently treated with low-dose statins, with LDL-cholesterol falling significantly by 38% (P < 0.001). The estimated cost per mmol/L reduction of LDL-cholesterol of a child receiving statins from ages 10 to 18 years is AU$1361, which can potentially be cost-effective. An LDL-cholesterol threshold of 3.5 mmol/L had a sensitivity of 92.8% and specificity of 96.6% for the detection of a mutation. CONCLUSION Genetic testing of children of affected parents with FH is an effective means of detecting new cases of FH. Cascade testing can enable early statin therapy with significant reductions in LDL-cholesterol concentration.
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Affiliation(s)
- Jing Pang
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Andrew C Martin
- Department of General Paediatrics, Princess Margaret Hospital for Children, Perth, Western Australia, Australia.,School of Paediatrics and Child Health, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia
| | - Timothy R Bates
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia.,St John of God Midland Public and Private Hospitals, Perth, Western Australia, Australia
| | - Amanda J Hooper
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia.,Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia
| | - Damon A Bell
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia.,Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia.,Lipid Disorders Clinic, Cardiometabolic Services, Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia
| | - John R Burnett
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia.,Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia.,Lipid Disorders Clinic, Cardiometabolic Services, Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Richard Norman
- School of Public Health, Curtin University, Perth, Western Australia, Australia
| | - Gerald F Watts
- School of Medicine, Faculty of Health and Medical Sciences, University of Western Australia, Perth, Western Australia, Australia.,Lipid Disorders Clinic, Cardiometabolic Services, Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia
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Chan DC, Pang J, Hooper AJ, Bell DA, Bates TR, Burnett JR, Watts GF. A Comparative Analysis of Phenotypic Predictors of Mutations in Familial Hypercholesterolemia. ATHEROSCLEROSIS SUPP 2018. [DOI: 10.1016/j.atherosclerosissup.2018.04.208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Abstract
PURPOSE OF REVIEW We review the role, utility and current status of patient registries for rare genetic lipid disorders. RECENT FINDINGS The creation and maintenance of rare genetic lipid disorder patient registries is critical for disease monitoring, improving clinical best practice, facilitating research and enabling the development of novel therapeutics. An open-source disease registry platform, termed the Rare Disease Registry Framework, has been developed, optimized and deployed for homozygous familial hypercholesterolemia. A global disease-specific registry for lipoprotein lipase deficiency (LPLD), GENetherapy In the mAnagement of Lipoprotein Lipase deficiency, has been established with the aim of enrolling 20-40% of LPLD patients worldwide and will study the natural history of LPLD as well as therapeutic response to the gene therapy alipogene tiparvovec. Similarly, a registry for lysosomal acid lipase deficiency patients in Europe and the United States is studying the clinical outcomes of the enzyme-replacement therapy sebelipase alfa. SUMMARY There are currently few disease-specific rare lipid disorder patient registries. The very nature of rare genetic lipid disorders would suggest that larger national or international registries are necessary to capture clinical data on a sufficient number of patients to provide insight into the prevalence and natural history of these conditions. Furthermore, these registries can help to identify and address deficiencies in current diagnostic and management practices, and facilitate clinical trials of new therapies.
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Affiliation(s)
- David M Ng
- School of Medicine, Faculty of Health & Medical Sciences, University of Western Australia
| | | | - Matthew I Bellgard
- Centre for Comparative Genomics, Murdoch University, Perth, Western Australia, Australia
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Chan DC, Pang J, Hooper AJ, Bell DA, Bates TR, Burnett JR, Watts GF. A Comparative Analysis of Phenotypic Predictors of Mutations in Familial Hypercholesterolemia. J Clin Endocrinol Metab 2018; 103:1704-1714. [PMID: 29408959 DOI: 10.1210/jc.2017-02622] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 01/29/2018] [Indexed: 02/13/2023]
Abstract
CONTEXT The gold standard for diagnosing familial hypercholesterolemia (FH) is identification of a causative pathogenic mutation. However, genetic testing is expensive and not widely available. OBJECTIVE To compare the validity of the Dutch Lipid Clinic Network (DLCN), Simon Broome (SB), Make Early Diagnosis to Prevent Early Deaths (MEDPED), and American Heart Association (AHA) criteria in predicting an FH-causing mutation. DESIGN, SETTING, AND PATIENTS An adult cohort of unrelated patients referred to a lipid clinic for genetic testing. MAIN OUTCOME MEASURES Odds ratio (OR), area under the curve (AUC), sensitivity, and specificity. RESULTS A pathogenic FH-causing mutation was detected in 30% of 885 patients tested. Elevated low-density lipoprotein (LDL) cholesterol and personal or family history of tendon xanthomata were independent predictors of a mutation (OR range 5.3 to 16.1, P < 0.001). Prediction of a mutation for the DLCN and SB definite and MEDPED criteria (ORs 9.4, 11.7, and 10.5, respectively) was higher than with the AHA criteria (OR 4.67). The balance of sensitivity and specificity was in decreasing order DLCN definite (Youden Index 0.487), MEDPED (0.457), SB definite (0.274), and AHA criteria (0.253), AUC being significantly higher with DLCN definite and MEDPED than other criteria (P < 0.05). Pretreatment LDL cholesterol and tendon xanthomata had the highest AUC in predicting a mutation. CONCLUSIONS The DLCN, SB, and MEDPED criteria are valid predictors of an FH-causing mutation in patients referred to a lipid clinic, but concordance between these phenotypic criteria is only moderate. Use of pretreatment LDL cholesterol and tendon xanthomata alone may be particularly useful for deciding who should be genetically tested for FH.
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Affiliation(s)
- Dick C Chan
- School of Medicine, University of Western Australia, Perth, Western Australia, Australia
| | - Jing Pang
- School of Medicine, University of Western Australia, Perth, Western Australia, Australia
| | - Amanda J Hooper
- School of Medicine, University of Western Australia, Perth, Western Australia, Australia
- Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia
| | - Damon A Bell
- School of Medicine, University of Western Australia, Perth, Western Australia, Australia
- Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia
- Lipid Disorders Clinic, Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Timothy R Bates
- School of Medicine, University of Western Australia, Perth, Western Australia, Australia
- St. John of God Midland Public and Private Hospitals, Midland, Western Australia, Australia
| | - John R Burnett
- School of Medicine, University of Western Australia, Perth, Western Australia, Australia
- Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia
- Lipid Disorders Clinic, Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Gerald F Watts
- School of Medicine, University of Western Australia, Perth, Western Australia, Australia
- Lipid Disorders Clinic, Department of Cardiology, Royal Perth Hospital, Perth, Western Australia, Australia
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Ellis KL, Pang J, Chieng D, Bell DA, Burnett JR, Schultz CJ, Hillis GS, Watts GF. Elevated lipoprotein(a) and familial hypercholesterolemia in the coronary care unit: Between Scylla and Charybdis. Clin Cardiol 2018; 41:378-384. [PMID: 29480541 DOI: 10.1002/clc.22880] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 12/21/2017] [Accepted: 12/27/2017] [Indexed: 01/05/2023] Open
Abstract
BACKGROUND Elevated lipoprotein(a) (Lp[a]) and familial hypercholesterolemia (FH) are inherited lipid disorders. Their frequencies, coexistence, and associations with premature coronary artery disease (CAD) in patients admitted to the coronary care unit (CCU) remain to be defined. HYPOTHESIS Elevated Lp(a) and FH are commonly encountered among CCU patients and independently associated with increased premature CAD risk. METHODS Plasma Lp(a) concentrations were measured in consecutive patients admitted to the CCU with an acute coronary syndrome (ACS) or prior history of CAD for 6.5 months. Elevated Lp(a) was defined as concentrations ≥0.5 g/L. Patients with LDL-C ≥ 5 mmol/L exhibited phenotypic FH. Premature CAD was diagnosed in those age < 60 years, and the relationship between this and elevated Lp(a) and FH was determined by logistic regression. RESULTS 316 patients were screened; 163 (51.6%) had premature CAD. Overall, elevated Lp(a) and FH were identified in 27.0% and 11.6% of patients, respectively. Both disorders were detected in 4.4% of individuals. Elevated Lp(a) (32.0% vs 22.2%; P = 0.019) and FH phenotype (15.5% vs 8.0%; P = 0.052) were more common with premature vs nonpremature CAD. Elevated Lp(a) alone conferred a 1.9-fold, FH alone a 3.2-fold, and the combination a 5.3-fold increased risk of premature CAD (P = 0.005). CONCLUSIONS Elevated Lp(a) and phenotypic FH were commonly encountered and more frequent with premature CAD. The combination of both disorders is especially associated with increased CAD risk. Patients admitted to the CCU with ACS or previously documented CAD should be routinely screened for elevated Lp(a) and FH.
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Affiliation(s)
- Katrina L Ellis
- School of Medicine, University of Western Australia, Perth, Australia.,School of Biomedical Sciences, University of Western Australia, Perth, Australia
| | - Jing Pang
- School of Medicine, University of Western Australia, Perth, Australia
| | - David Chieng
- Department of Cardiology, Royal Perth Hospital, Perth, Australia
| | - Damon A Bell
- School of Medicine, University of Western Australia, Perth, Australia.,Department of Cardiology, Royal Perth Hospital, Perth, Australia
| | - John R Burnett
- School of Medicine, University of Western Australia, Perth, Australia.,Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Australia
| | - Carl J Schultz
- School of Medicine, University of Western Australia, Perth, Australia.,Department of Cardiology, Royal Perth Hospital, Perth, Australia
| | - Graham S Hillis
- School of Medicine, University of Western Australia, Perth, Australia.,Department of Cardiology, Royal Perth Hospital, Perth, Australia
| | - Gerald F Watts
- School of Medicine, University of Western Australia, Perth, Australia.,Department of Cardiology, Royal Perth Hospital, Perth, Australia
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Faraj J, Mander J, Burnett JR, Prentice D. Filiarial chyluria with nephrotic-range proteinuria and associated hypoalbuminaemia and hypogammaglobulinaemia secondary to bilateral lymphorenal fistulae. BMJ Case Rep 2017; 2017:bcr-2017-221114. [PMID: 28978592 DOI: 10.1136/bcr-2017-221114] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
A 55-year-old man of Indian descent, presented to the emergency department with a 2-year history of passing 'milky' white urine, associated with dysuria, urinary retention, bilateral flank pain and 15 kg weight loss. He had migrated to Australia from India at the age of 16, with no overseas travel since, and denied having any fevers, rigours or chills. He was found to have chyluria and nephrotic-range proteinuria with marked hypoalbuminaemia and hypogammaglobulinaemia. Due to his ethnic origin and by diagnostic exclusion, a presumptive diagnosis of filariasis was made. With bilateral lymphorenal disconnection, as definitive management, the patient's chyluria and proteinuria resolved with restoration of normal plasma protein and immunoglobulin levels.
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Affiliation(s)
- Joseph Faraj
- Department of Urology, Royal Perth Hospital, Perth, Western Australia, Australia
| | - Julian Mander
- Department of Urology, Royal Perth Hospital, Perth, Western Australia, Australia
| | - John R Burnett
- Department of Clinical Biochemistry, Royal Perth Hospital, Perth, Western Australia, Australia.,School of Medicine, University of Western Australia, Perth, Australia
| | - David Prentice
- Department of Internal Medicine, Royal Perth Hospital, Perth, Western Australia, Australia
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Vidanapathirana DM, Rodrigo T, Waidyanatha S, Jasinge E, Hooper AJ, Burnett JR. Lipoprotein Lipase Deficiency in an Infant With Chylomicronemia, Hepatomegaly, and Lipemia Retinalis. Glob Pediatr Health 2017; 4:2333794X17715839. [PMID: 28695157 PMCID: PMC5495498 DOI: 10.1177/2333794x17715839] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Accepted: 05/11/2017] [Indexed: 11/19/2022] Open
Affiliation(s)
| | | | | | | | - Amanda J Hooper
- Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia.,University of Western Australia, Crawley, Western Australia, Australia
| | - John R Burnett
- Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia.,University of Western Australia, Crawley, Western Australia, Australia
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Sorubarajan T, Lewis BD, Burnett JR, Martin AC. Documenting family history in children with hypercholesterolaemia: A lost opportunity. J Paediatr Child Health 2017; 53:470-473. [PMID: 28045210 DOI: 10.1111/jpc.13457] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Revised: 10/26/2016] [Accepted: 11/06/2016] [Indexed: 10/20/2022]
Abstract
AIM To determine whether information about a family history of hypercholesterolaemia or early cardiovascular disease was documented by paediatricians in children and adolescents with elevated low-density lipoprotein (LDL)-cholesterol levels. METHODS Retrospective chart review of all children with a LDL-cholesterol level ≥95th percentile (3.4 mmol/L) and ≥99th percentile (3.8 mmol/L) at a tertiary paediatric hospital in 2014. RESULTS Of 86 children with a LDL-cholesterol level ≥3.4 mmol/L, only 18 (20.9%) had documentation of a family history of hypercholesterolaemia or early cardiovascular disease. In those 18, 13 (72.2%) had a family history of hypercholesterolaemia and 11 (61.1%) a family history of early cardiovascular disease. Increasing the LDL-cholesterol cut-off level to ≥3.8 mmol/L (n = 46) did not improve documentation of a family history (9/46, 19.6%). CONCLUSIONS In patients with elevated LDL-cholesterol levels, paediatricians rarely document a positive or negative family history of hypercholesterolaemia or early cardiovascular disease. This represents a lost opportunity to diagnose children and adolescents with familial hypercholesterolaemia.
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Affiliation(s)
- Tharmarajah Sorubarajan
- Department of General Paediatrics, Princess Margaret Hospital for Children, Perth, Western Australia, Australia
| | - Barry D Lewis
- Department of Clinical Biochemistry, PathWest Laboratory Medicine, Princess Margaret Hospital for Children, Queen Elizabeth Medical Centre Network, Perth, Western Australia, Australia
| | - John R Burnett
- Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia.,School of Medicine and Pharmacology, University of Western Australia, Perth, Western Australia, Australia
| | - Andrew C Martin
- Department of General Paediatrics, Princess Margaret Hospital for Children, Perth, Western Australia, Australia
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Page MM, Hooper AJ, Glendenning P, Burnett JR. Isolated brachydactyly type E and idiopathic pancreatitis in a patient presenting to a lipid disorders clinic. BMJ Case Rep 2017; 2017:bcr-2016-218825. [PMID: 28385908 DOI: 10.1136/bcr-2016-218825] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
An 18-year-old female tertiary student was referred to a lipid clinic with hypertriglyceridaemia discovered after presentation with acute pancreatitis. The patient's only medication was l-thyroxine for treatment of hypothyroidism. She was overweight, normotensive, with unremarkable facies. However, she had hypermobile hand joints and brachydactyly resulting in loss of left 3-5 and right 4 and 5 knuckle definitions. Radiography revealed shortening of metacarpals 3-5 on the left and 4 and 5 on the right. Her mother had similar skeletal changes, consistent with a dominant mode of inheritance. Abnormally short digits involving the metacarpals, classified as brachydactyly type E, can be isolated or occur as part of a syndrome. Turner syndrome, Albright hereditary osteodystrophy, hypertension with brachydactyly, chromosome 2q37 microdeletion and PTHLH mutations were excluded following clinical, biochemical and genetic testing. No specific treatment was required. Genetic testing for isolated and syndromic forms of brachydactyly facilitates family screening and prepregnancy counselling.
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Affiliation(s)
- Michael M Page
- Department of Clinical Biochemistry, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Australia.,School of Medicine and Pharmacology, University of Western Australia, Perth, Australia
| | - Amanda J Hooper
- Department of Clinical Biochemistry, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Australia.,School of Medicine and Pharmacology, University of Western Australia, Perth, Australia.,School of Pathology and Laboratory Medicine, University of Western Australia, Perth, Australia
| | - Paul Glendenning
- Department of Clinical Biochemistry, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Australia.,School of Medicine and Pharmacology, University of Western Australia, Perth, Australia
| | - John R Burnett
- Department of Clinical Biochemistry, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Australia .,School of Medicine and Pharmacology, University of Western Australia, Perth, Australia
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Nguyen LT, Burnett JR, Bell DA, Watts GF, Bates TR, Pang J, Allcock R, Hooper AJ. Improved detection of genetic hypercholesterolaemia using a custom cardiometabolic gene panel. Pathology 2017. [DOI: 10.1016/j.pathol.2016.12.276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Chan DC, Pang J, Barrett PHR, Sullivan DR, Mori TA, Burnett JR, van Bockxmeer FM, Watts GF. Effect of omega-3 fatty acid supplementation on arterial elasticity in patients with familial hypercholesterolaemia on statin therapy. Nutr Metab Cardiovasc Dis 2016; 26:1140-1145. [PMID: 27614801 DOI: 10.1016/j.numecd.2016.07.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/09/2016] [Revised: 07/19/2016] [Accepted: 07/26/2016] [Indexed: 11/24/2022]
Abstract
BACKGROUND AND AIMS Increased arterial stiffness is closely linked with raised blood pressure that contributes substantially to enhanced risk of coronary heart disease in high risk individuals with familial hypercholesterolaemia (FH). Omega-3 fatty acid (ω3-FA) supplementation has been demonstrated to lower blood pressure in subjects with a high cardiovascular disease risk. Whether ω3-FA supplementation improves arterial stiffness in FH subjects, on background statin therapy, has yet to be investigated. METHOD AND RESULTS We carried out an 8-week randomized, crossover intervention trial to test the effect of 4 g/d ω3-FA supplementation (46% eicosapentaenoic acid and 38% docosahexaenoic acid) on arterial elasticity in 20 adults with FH on optimal cholesterol-lowering therapy. Large and small artery elasticity were measured by pulse contour analysis of the radial artery. ω3-FA supplementation significantly (P < 0.05 in all) increased large artery elasticity (+9%) and reduced systolic blood pressure (-6%) and diastolic blood pressure (-6%), plasma triglycerides (-20%), apoB concentration (-8%). In contrast, ω3-FAs had no significant effect on small artery elasticity. The change in large artery elasticity was not significantly associated with changes in systolic blood pressure or plasma triglyceride concentration. CONCLUSIONS ω3-FA supplementation improves large arterial elasticity and arterial blood pressure independent of statin therapy in adults with FH. CLINICAL TRIAL REGISTRATION https://www.clinicaltrials.com/NCT01577056.
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Affiliation(s)
- D C Chan
- School of Medicine and Pharmacology, University of Western Australia, Perth, Western Australia, Australia
| | - J Pang
- School of Medicine and Pharmacology, University of Western Australia, Perth, Western Australia, Australia
| | - P H R Barrett
- School of Medicine and Pharmacology, University of Western Australia, Perth, Western Australia, Australia; Faculty of Engineering, Computing and Mathematics, University of Western Australia, Perth, Western Australia, Australia
| | - D R Sullivan
- Department of Clinical Biochemistry, Royal Prince Alfred Hospital, Sydney, Australia
| | - T A Mori
- School of Medicine and Pharmacology, University of Western Australia, Perth, Western Australia, Australia
| | - J R Burnett
- School of Medicine and Pharmacology, University of Western Australia, Perth, Western Australia, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Australia
| | - F M van Bockxmeer
- Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Australia; School of Surgery, University of Western Australia, Perth, Australia
| | - G F Watts
- School of Medicine and Pharmacology, University of Western Australia, Perth, Western Australia, Australia.
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Ellis KL, Pang J, Chan DC, Hooper AJ, Bell DA, Burnett JR, Watts GF. Familial combined hyperlipidemia and hyperlipoprotein(a) as phenotypic mimics of familial hypercholesterolemia: Frequencies, associations and predictions. J Clin Lipidol 2016; 10:1329-1337.e3. [DOI: 10.1016/j.jacl.2016.08.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2016] [Revised: 08/11/2016] [Accepted: 08/16/2016] [Indexed: 12/11/2022]
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40
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Chan DC, Pang J, Barrett PHR, Sullivan DR, Burnett JR, van Bockxmeer FM, Watts GF. ω-3 Fatty Acid Ethyl Esters Diminish Postprandial Lipemia in Familial Hypercholesterolemia. J Clin Endocrinol Metab 2016; 101:3732-3739. [PMID: 27490922 DOI: 10.1210/jc.2016-2217] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
CONTEXT Impaired postprandial chylomicron metabolism induces hypertriglyceridemia and may increase the risk of atherosclerotic cardiovascular disease. Omega-3 fatty acid ethyl ester (ω-3 FAEE) supplementation decreases plasma triglycerides. However, its effect on postprandial chylomicron metabolism in familial hypercholesterolemia (FH) has not yet been investigated. OBJECTIVE We aimed to examine the effect of ω-3 FAEE supplementation on postprandial responses in plasma triglycerides, very-low-density lipoprotein (VLDL) apolipoprotein B (apoB)-100, and apoB-48 in FH patients receiving standard cholesterol-lowering treatment. DESIGN, SETTING, AND PATIENTS We carried out an 8-week open-label, randomized, crossover intervention trial to test the effect of oral supplementation with 4 g/d ω-3 FAEE (46% eicosapentaenoic acid and 38% docosahexaenoic acid) on postprandial triglyceride, VLDL-apoB-100, and apoB-48 responses in FH patients after ingestion of an oral fat load. OUTCOMES MEASURES Plasma total and incremental triglyceride, VLDL-apoB-100, and apoB-48 0- to 10-hour area under the curve (AUC). RESULTS ω-3 FAEE supplementation significantly (P < .05 in all) reduced concentrations of fasting plasma triglyceride (-20%), apoB (-8%), VLDL-apoB-100 (-26%), and apoB-48 (-36%); as well as systolic blood pressure (-6%) and diastolic blood pressure (-6%). Postprandial triglyceride and VLDL-apoB-100 total AUCs (-19% and -26%, respectively; P < .01) and incremental AUCs (-18% and -35%, respectively; P < .05), as well as postprandial apoB-48 total AUC (-30%; P < .02) were significantly reduced by ω-3 FAEE supplementation. CONCLUSION Supplementation with ω-3 FAEEs improves postprandial lipemia in FH patients receiving standard care; this may have implications for further reducing atherosclerotic cardiovascular disease in this high-risk patient group.
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Affiliation(s)
- Dick C Chan
- School of Medicine and Pharmacology (D.C.C., J.P., P.H.R.B., J.R.B., G.F.W.), Faculty of Engineering, Computing, and Mathematics (P.H.R.B.), and School of Surgery (F.M.v.B.), University of Western Australia, Perth, Western Australia 6847, Australia; Department of Clinical Biochemistry (D.R.S.), Royal Prince Alfred Hospital, Camperdown, New South Wales 2050, Australia; and Department of Clinical Biochemistry (J.R.B., F.M.v.B.), PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia 6000, Australia
| | - Jing Pang
- School of Medicine and Pharmacology (D.C.C., J.P., P.H.R.B., J.R.B., G.F.W.), Faculty of Engineering, Computing, and Mathematics (P.H.R.B.), and School of Surgery (F.M.v.B.), University of Western Australia, Perth, Western Australia 6847, Australia; Department of Clinical Biochemistry (D.R.S.), Royal Prince Alfred Hospital, Camperdown, New South Wales 2050, Australia; and Department of Clinical Biochemistry (J.R.B., F.M.v.B.), PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia 6000, Australia
| | - P Hugh R Barrett
- School of Medicine and Pharmacology (D.C.C., J.P., P.H.R.B., J.R.B., G.F.W.), Faculty of Engineering, Computing, and Mathematics (P.H.R.B.), and School of Surgery (F.M.v.B.), University of Western Australia, Perth, Western Australia 6847, Australia; Department of Clinical Biochemistry (D.R.S.), Royal Prince Alfred Hospital, Camperdown, New South Wales 2050, Australia; and Department of Clinical Biochemistry (J.R.B., F.M.v.B.), PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia 6000, Australia
| | - David R Sullivan
- School of Medicine and Pharmacology (D.C.C., J.P., P.H.R.B., J.R.B., G.F.W.), Faculty of Engineering, Computing, and Mathematics (P.H.R.B.), and School of Surgery (F.M.v.B.), University of Western Australia, Perth, Western Australia 6847, Australia; Department of Clinical Biochemistry (D.R.S.), Royal Prince Alfred Hospital, Camperdown, New South Wales 2050, Australia; and Department of Clinical Biochemistry (J.R.B., F.M.v.B.), PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia 6000, Australia
| | - John R Burnett
- School of Medicine and Pharmacology (D.C.C., J.P., P.H.R.B., J.R.B., G.F.W.), Faculty of Engineering, Computing, and Mathematics (P.H.R.B.), and School of Surgery (F.M.v.B.), University of Western Australia, Perth, Western Australia 6847, Australia; Department of Clinical Biochemistry (D.R.S.), Royal Prince Alfred Hospital, Camperdown, New South Wales 2050, Australia; and Department of Clinical Biochemistry (J.R.B., F.M.v.B.), PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia 6000, Australia
| | - Frank M van Bockxmeer
- School of Medicine and Pharmacology (D.C.C., J.P., P.H.R.B., J.R.B., G.F.W.), Faculty of Engineering, Computing, and Mathematics (P.H.R.B.), and School of Surgery (F.M.v.B.), University of Western Australia, Perth, Western Australia 6847, Australia; Department of Clinical Biochemistry (D.R.S.), Royal Prince Alfred Hospital, Camperdown, New South Wales 2050, Australia; and Department of Clinical Biochemistry (J.R.B., F.M.v.B.), PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia 6000, Australia
| | - Gerald F Watts
- School of Medicine and Pharmacology (D.C.C., J.P., P.H.R.B., J.R.B., G.F.W.), Faculty of Engineering, Computing, and Mathematics (P.H.R.B.), and School of Surgery (F.M.v.B.), University of Western Australia, Perth, Western Australia 6847, Australia; Department of Clinical Biochemistry (D.R.S.), Royal Prince Alfred Hospital, Camperdown, New South Wales 2050, Australia; and Department of Clinical Biochemistry (J.R.B., F.M.v.B.), PathWest Laboratory Medicine, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia 6000, Australia
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Al-Mahdili HA, Hooper AJ, Sullivan DR, Stewart PM, Burnett JR. A mild case of abetalipoproteinaemia in association with subclinical hypothyroidism. Ann Clin Biochem 2016; 43:516-9. [PMID: 17132287 DOI: 10.1258/000456306778904650] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Abetalipoproteinaemia (ABL), an extremely rare recessive disorder, is characterized by exceptionally low or undetectable concentrations of apolipoprotein (apo) B-containing lipoproteins. ABL results from mutations in the gene encoding microsomal triglyceride transfer protein (MTP), a chaperone that facilitates the transfer of lipids onto apoB. Patients with ABL often present in childhood with a range of symptoms including fat malabsorption and manifestations of fat-soluble vitamin deficiencies. We describe a patient with sub-clinical hypothyroidism and ABL found to be compound heterozygous for a novel splice site mutation of intron 1 (c.61 + 2T > C) and a single adenine insertion in MTP exon 4 (c.419-420insA) that results in a frameshift and a protein truncated at 140 amino acids.
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Affiliation(s)
- Huda A Al-Mahdili
- Department of Clinical Biochemistry, Royal Prince Alfred Hospital, Camperdown, NSW, Australia.
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42
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Tani M, Horvath KV, Lamarche B, Couture P, Burnett JR, Schaefer EJ, Asztalos BF. High-density lipoprotein subpopulation profiles in lipoprotein lipase and hepatic lipase deficiency. Atherosclerosis 2016; 253:7-14. [PMID: 27573733 DOI: 10.1016/j.atherosclerosis.2016.08.014] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 08/01/2016] [Accepted: 08/18/2016] [Indexed: 11/26/2022]
Abstract
BACKGROUND AND AIMS Our aim was to gain insight into the role that lipoprotein lipase (LPL) and hepatic lipase (HL) plays in HDL metabolism and to better understand LPL- and HL-deficiency states. METHODS We examined the apolipoprotein (apo) A-I-, A-II-, A-IV-, C-I-, C-III-, and E-containing HDL subpopulation profiles, assessed by native 2-dimensional gel-electrophoresis and immunoblotting, in 6 homozygous and 11 heterozygous LPL-deficient, 6 homozygous and 4 heterozygous HL-deficient, and 50 control subjects. RESULTS LPL-deficient homozygotes had marked hypertriglyceridemia and significant decreases in LDL-C, HDL-C, and apoA-I. Their apoA-I-containing HDL subpopulation profile was shifted toward small HDL particles compared to controls. HL-deficient homozygotes had moderate hypertriglyceridemia, modest increases in LDL-C and HDL-C level, but normal apoA-I concentration. HL-deficient homozygotes had a unique distribution of apoA-I-containing HDL particles. The normally apoA-I:A-II, intermediate-size (α-2 and α-3) particles were significantly decreased, while the normally apoA-I only (very large α-1, small α-4, and very small preβ-1) particles were significantly elevated. In contrast to control subjects, the very large α-1 particles of HL-deficient homozygotes were enriched in apoA-II. Homozygous LPL- and HL-deficient subjects also had abnormal distributions of apo C-I, C-III, and E in HDL particles. Values for all measured parameters in LPL- and HL-deficient heterozygotes were closer to values measured in controls than in homozygotes. CONCLUSIONS Our data are consistent with the concept that LPL is important for the maturation of small discoidal HDL particles into large spherical HDL particles, while HL is important for HDL remodeling of very large HDL particles into intermediate-size HDL particles.
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Affiliation(s)
- Mariko Tani
- Cardiovascular Nutrition Laboratory, Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA
| | - Katalin V Horvath
- Cardiovascular Nutrition Laboratory, Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA
| | - Benoit Lamarche
- Institute on Nutraceuticals and Functional Foods, Laval University, Québec, Canada
| | - Patrick Couture
- Institute on Nutraceuticals and Functional Foods, Laval University, Québec, Canada
| | - John R Burnett
- Department of Clinical Biochemistry, Path West Laboratory Medicine, Royal Perth and Fiona Stanley Hospital Network and School of Medicine and Pharmacology, University of Western Australia, Perth, Australia
| | - Ernst J Schaefer
- Cardiovascular Nutrition Laboratory, Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA
| | - Bela F Asztalos
- Cardiovascular Nutrition Laboratory, Human Nutrition Research Center on Aging at Tufts University, Boston, MA, USA.
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Abstract
Familial hypercholesterolaemia, familial combined hyperlipidaemia (FCH) and elevated lipoprotein(a) are common, inherited disorders of apolipoprotein B metabolism that markedly accelerate the onset of atherosclerotic cardiovascular disease (ASCVD). These disorders are frequently encountered in clinical lipidology and need to be accurately identified and treated in both index patients and their family members, to prevent the development of premature ASCVD. The optimal screening strategies depend on the patterns of heritability for each condition. Established therapies are widely used along with lifestyle interventions to regulate levels of circulating lipoproteins. New therapeutic strategies are becoming available, and could supplement traditional approaches in the most severe cases, but their long-term cost-effectiveness and safety have yet to be confirmed. We review contemporary developments in the understanding, detection and care of these highly atherogenic disorders of apolipoprotein B metabolism.
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Affiliation(s)
- Katrina L Ellis
- School of Medicine and Pharmacology, The University of Western Australia, PO Box X2213, Perth, Western Australia 6847, Australia
- Centre for Genetic Origins of Health and Disease, The University of Western Australia and Curtin University, 35 Stirling Highway, Crawley, Perth, Western Australia 6009, Australia
| | - Amanda J Hooper
- School of Medicine and Pharmacology, The University of Western Australia, PO Box X2213, Perth, Western Australia 6847, Australia
- PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia
- School of Pathology and Laboratory Medicine, The University of Western Australia, 35 Stirling Highway, Crawley, Perth, Western Australia 6009, Australia
| | - John R Burnett
- School of Medicine and Pharmacology, The University of Western Australia, PO Box X2213, Perth, Western Australia 6847, Australia
- PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, Western Australia, Australia
- Lipid Disorders Clinic, Department of Cardiology, Royal Perth Hospital, Wellington Street Perth, Western Australia, Australia
| | - Gerald F Watts
- School of Medicine and Pharmacology, The University of Western Australia, PO Box X2213, Perth, Western Australia 6847, Australia
- Lipid Disorders Clinic, Department of Cardiology, Royal Perth Hospital, Wellington Street Perth, Western Australia, Australia
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Bender R, Edwards G, McMahon J, Hooper AJ, Watts GF, Burnett JR, Bell DA. Interpretative comments specifically suggesting specialist referral increase the detection of familial hypercholesterolaemia. Pathology 2016; 48:463-6. [PMID: 27328651 DOI: 10.1016/j.pathol.2016.04.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 04/01/2016] [Accepted: 04/06/2016] [Indexed: 11/30/2022]
Abstract
Familial hypercholesterolaemia (FH) is an under-diagnosed inherited condition characterised by elevated low density lipoprotein (LDL)-cholesterol and premature coronary artery disease. The requesting general practitioner of individuals with extremely elevated LDL-cholesterol measured by St John of God Pathology receives an interpretative comment on the lipid results highlighting possible FH. We sought to determine whether specifically recommending referral to the regional Lipid Disorders Clinic (LDC) increased referral and FH detection rates. A prospective case-control study of individuals with LDL-cholesterol ≥6.5 mmol/L was conducted. All individuals received an interpretative comment highlighting the possibility of FH. The cases comment also suggested LDC referral, and a subset of cases received the LDC's fax number (fax-cases) in addition. There were 231 individuals with an LDL-cholesterol ≥6.5 mmol/L; 96 (42%) controls and 135 (58%) cases, of which 99 were fax-cases. Twenty-four (18%) cases were referred to clinic compared with eight (8%) controls (p = 0.035). After specialist review and genetic testing, four probable and four definite FH individuals were detected amongst controls, compared with seven possible, eight probable and nine definite FH amongst cases. Genetic testing was performed in 31 (94%) individuals, 13 (42%) had a causative mutation identified. Interpretative commenting specifically recommending specialist review augments the detection of FH in the community.
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Affiliation(s)
- Robert Bender
- Cardiometabolic Service, Royal Perth Hospital, Perth, WA, Australia
| | - Glenn Edwards
- Department of Clinical Biochemistry, St John of God Pathology, Osborne Park, Perth, WA, Australia
| | - Jenny McMahon
- Department of Clinical Biochemistry, St John of God Pathology, Osborne Park, Perth, WA, Australia
| | - Amanda J Hooper
- Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, WA, Australia; School of Medicine and Pharmacology, University of Western Australia, Perth, WA, Australia; School of Pathology and Laboratory Medicine, University of Western Australia, Perth, WA, Australia
| | - Gerald F Watts
- Cardiometabolic Service, Royal Perth Hospital, Perth, WA, Australia; School of Medicine and Pharmacology, University of Western Australia, Perth, WA, Australia
| | - John R Burnett
- Cardiometabolic Service, Royal Perth Hospital, Perth, WA, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, WA, Australia; School of Medicine and Pharmacology, University of Western Australia, Perth, WA, Australia
| | - Damon A Bell
- Cardiometabolic Service, Royal Perth Hospital, Perth, WA, Australia; Department of Clinical Biochemistry, St John of God Pathology, Osborne Park, Perth, WA, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital Network, Perth, WA, Australia; School of Medicine and Pharmacology, University of Western Australia, Perth, WA, Australia.
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45
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Hooper AJ, Robertson K, Champain D, Hua J, Song S, Parhofer KG, Barrett PHR, van Bockxmeer FM, Burnett JR. Lipoprotein metabolism in an apoB-80 familial hypobetalipoproteinemia heterozygote. Clin Biochem 2016; 49:720-722. [DOI: 10.1016/j.clinbiochem.2016.02.008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Revised: 02/17/2016] [Accepted: 02/19/2016] [Indexed: 11/30/2022]
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Miller SA, Hooper AJ, Mantiri GA, Marais D, Tanyanyiwa DM, McKnight J, Burnett JR. Novel APOB missense variants, A224T and V925L, in a black South African woman with marked hypocholesterolemia. J Clin Lipidol 2016; 10:604-9. [PMID: 27206948 DOI: 10.1016/j.jacl.2016.01.006] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2015] [Revised: 01/06/2016] [Accepted: 01/25/2016] [Indexed: 11/27/2022]
Abstract
BACKGROUND One genetic cause of markedly low plasma concentrations of apolipoprotein (apo) B and low density lipoprotein (LDL)-cholesterol is familial hypobetalipoproteinemia. OBJECTIVE We aimed to determine the molecular basis for the marked hypocholesterolemia consistent with heterozygous familial hypobetalipoproteinemia in a black female subject of Xhosa lineage. METHODS Coding regions of APOB, MTTP, PCSK9,ANGPTL3, SAR1B and APOC3 were sequenced, and APOE was genotyped. COS-7 cells were transfected with plasmids containing apoB variants. Western blotting was used to detect cellular and secreted apoB, and co-immunoprecipitation performed to assess binding with the microsomal triglyceride transfer protein (MTP). RESULTS Sequence analysis of the APOB gene revealed her to be heterozygous for two novel variants, c.751G>A (A224T) and c.2854G>C (V925L). She was also homozygous for the APOEε2 allele, and did not carry a PCSK9 loss-of-function mutation. Although Ala(224) is within the postulated MTP binding region in apoB, it is not conserved among mammalian species. Subsequent genotyping showed that Ala224Thr is found in a southern African population (n=654) with an allele frequency of 1.15% and is not associated with plasma lipid levels. Val(925), like Ala(224), is within the N-terminal 1000 amino acids required for lipoprotein assembly, but was not found in the population screen. However, in vitro studies showed that apoB V925L did not affect apoB48 production or secretion nor have a deleterious effect on MTP interaction with apoB. CONCLUSION Taken together, this suggests that the hypocholesterolemia in our case may be a result of being homozygous for APOEε2 with a low baseline cholesterol.
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Affiliation(s)
- Sharon A Miller
- School of Pathology and Laboratory Medicine, University of Western Australia, Perth, Australia
| | - Amanda J Hooper
- School of Pathology and Laboratory Medicine, University of Western Australia, Perth, Australia; School of Medicine and Pharmacology, University of Western Australia, Perth, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital, Perth, Western Australia, Australia
| | - George A Mantiri
- School of Pathology and Laboratory Medicine, University of Western Australia, Perth, Australia
| | - David Marais
- Division of Chemical Pathology, University of Cape Town, National Health Laboratory Service and MRC Cape Heart Group, Cape Town, South Africa
| | - Donald M Tanyanyiwa
- University of Witwatersrand and National Health Laboratory Service and Division of Human Genetics, University of Cape Town, Cape Town, South Africa
| | - James McKnight
- Department of Physiology & Biophysics, Boston University School of Medicine, Boston, MA, USA
| | - John R Burnett
- School of Medicine and Pharmacology, University of Western Australia, Perth, Australia; Department of Clinical Biochemistry, PathWest Laboratory Medicine WA, Royal Perth Hospital and Fiona Stanley Hospital, Perth, Western Australia, Australia.
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Abstract
Lipoprotein lipase (LPL), a member of the triglyceride lipase gene family, is synthesised by parenchymal cells of the heart, skeletal muscle and adipose tissues before being transported to luminal surfaces of vascular endothelial cells to exert its main physiological function to hydrolyse plasma lipoproteins. LPL deficiency is a rare autosomal recessive disorder, resulting in severe hypertriglyceridaemia from birth. The effect of marked hypertriglyceridaemia on the immune function in children has not been described. We present a case of a neonate with LPL deficiency and grossly elevated plasma triglyceride levels, presenting with recurrent and recalcitrant perianal abscesses suggestive of underlying immunodeficiency. With reduced levels of plasma triglycerides, the recurrent perianal infections resolved. This case report reviews evidence for potential deleterious effects of hypertriglyceridaemia on immune function, however, underlying mechanisms are poorly understood. Whether hypertriglyceridaemia contributes to immune dysfunction in this context is unknown. If there is a pathophysiological link, this may have implications for hypertriglyceridaemia management.
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Affiliation(s)
- Lauren S Akesson
- Telethon Kids Institute, West Perth, Western Australia, Australia School of Paediatrics and Child Health, University of Western Australia, Crawley, Western Australia, Australia Department of General Paediatrics, Princess Margaret Hospital for Children, Subiaco, Western Australia, Australia
| | - John R Burnett
- Department of Clinical Biochemistry, PathWest Laboratory Medicine, Royal Perth and Fiona Stanley Hospital Network, Perth, Western Australia, Australia School of Medicine and Pharmacology, University of Western Australia, Crawley, Western Australia, Australia
| | - Divyesh K Mehta
- School of Paediatrics and Child Health, University of Western Australia, Crawley, Western Australia, Australia Department of General Paediatrics, Princess Margaret Hospital for Children, Subiaco, Western Australia, Australia
| | - Andrew C Martin
- School of Paediatrics and Child Health, University of Western Australia, Crawley, Western Australia, Australia Department of General Paediatrics, Princess Margaret Hospital for Children, Subiaco, Western Australia, Australia
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Page MM, Hooper AJ, Burnett JR. Anacetrapib for the treatment of dyslipidaemia: the last bastion of the cholesteryl ester transfer protein inhibitors? Expert Opin Pharmacother 2015; 17:275-81. [PMID: 26642232 DOI: 10.1517/14656566.2016.1129402] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
INTRODUCTION Inhibition of cholesteryl ester transfer protein (CETP) has emerged as a potential way to decrease cardiovascular risk by raising high density lipoprotein (HDL) cholesterol and lowering low density lipoprotein (LDL) cholesterol concentrations. However, high profile withdrawals of several CETP inhibitors have cast doubt over this hypothesis. Despite this concern, anacetrapib appears to be safe, well-tolerated and delivers a substantial increases in HDL cholesterol and reductions in LDL cholesterol as monotherapy and when combined with a statin. AREAS COVERED We discuss the role of CETP and HDL cholesterol as therapeutic targets, describe the pharmacokinetics and pharmacodynamics of anacetrapib, as well as report on the recent clinical trials. EXPERT OPINION The focus of CETP inhibition has shifted from HDL cholesterol-raising to LDL cholesterol-lowering. Although anacetrapib appears to be safe and is effective in altering lipid-related biochemical parameters of interest, its effect on cardiovascular outcomes remains unknown. Extrapolation of LDL cholesterol lowering to improved cardiovascular outcomes is not possible, because LDL and HDL functionality in the setting of anacetrapib treatment is unclear. The results of the phase III REVEAL randomised controlled trial will be critical for anacetrapib to establish a place in clinical care.
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Affiliation(s)
- Michael M Page
- a Department of Clinical Biochemistry, PathWest Laboratory Medicine WA , Royal Perth Hospital and Fiona Stanley Hospital Network , Perth , Australia
| | - Amanda J Hooper
- a Department of Clinical Biochemistry, PathWest Laboratory Medicine WA , Royal Perth Hospital and Fiona Stanley Hospital Network , Perth , Australia.,b School of Medicine & Pharmacology , University of Western Australia , Perth , Australia.,c School of Pathology & Laboratory Medicine , University of Western Australia , Perth , Australia
| | - John R Burnett
- a Department of Clinical Biochemistry, PathWest Laboratory Medicine WA , Royal Perth Hospital and Fiona Stanley Hospital Network , Perth , Australia.,b School of Medicine & Pharmacology , University of Western Australia , Perth , Australia
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49
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Chan DC, Pang J, Hooper AJ, Burnett JR, Bell DA, Bates TR, van Bockxmeer FM, Watts GF. Elevated lipoprotein(a), hypertension and renal insufficiency as predictors of coronary artery disease in patients with genetically confirmed heterozygous familial hypercholesterolemia. Int J Cardiol 2015; 201:633-8. [DOI: 10.1016/j.ijcard.2015.08.146] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Revised: 07/22/2015] [Accepted: 08/20/2015] [Indexed: 12/16/2022]
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50
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Hooper AJ, Heeks L, Robertson K, Champain D, Hua J, Song S, Parhofer KG, Barrett PHR, van Bockxmeer FM, Burnett JR. Lipoprotein Metabolism in APOB L343V Familial Hypobetalipoproteinemia. J Clin Endocrinol Metab 2015; 100:E1484-90. [PMID: 26323024 DOI: 10.1210/jc.2015-2731] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
CONTEXT Familial hypobetalipoproteinemia (FHBL) is a codominant disorder of lipoprotein metabolism characterized by decreased plasma concentrations of low-density lipoprotein (LDL)-cholesterol and apolipoprotein B (apoB). OBJECTIVE The objective was to examine the effect of heterozygous APOB L343V FHBL on postprandial triglyceride-rich lipoprotein (TRL) and fasting lipoprotein metabolism. METHODS Plasma incremental area under the curve apoB-48 and apoB-48 kinetics were determined after ingestion of a standardized oral fat load using compartmental modeling. Very low-density lipoprotein (VLDL)-, intermediate-density lipoprotein (IDL)-, and LDL-apoB kinetics were determined in the fasting state using stable isotope methods and compartmental modeling. RESULTS The postprandial incremental area under the curve (0-10 h) in FHBL subjects (n = 3) was lower for large TRL-triglyceride (-77%; P < .0001), small TRL-cholesterol (-83%; P < .001), small TRL-triglyceride (-88%; P < .001), and for plasma triglyceride (-70%; P < .01) and apoB (-63%; P < .0001) compared with controls. Compartmental analysis showed that apoB-48 production was lower (-91%; P < .05) compared with controls. VLDL-apoB concentrations in FHBL subjects (n = 2) were lower by more than 75% compared with healthy, normolipidemic control subjects (P < .01). The VLDL-apoB fractional catabolic rate (FCR) was more than 5-fold higher in the FHBL subjects (P = .07). ApoB production rates and IDL- and LDL-apoB FCRs were not different between FHBL subjects and controls. CONCLUSIONS We conclude that when compared to controls, APOB L343V FHBL heterozygotes show lower TRL production with normal postprandial TRL particle clearance. In contrast, VLDL-apoB production was normal, whereas the FCR was higher in heterozygotes compared with lean control subjects. These mechanisms account for the marked hypolipidemic state observed in these FHBL subjects.
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MESH Headings
- Adult
- Amino Acid Substitution
- Apolipoprotein B-48/blood
- Apolipoprotein B-48/metabolism
- Apolipoproteins B/blood
- Apolipoproteins B/genetics
- Apolipoproteins B/metabolism
- Diet, High-Fat/adverse effects
- Down-Regulation
- Female
- Heterozygote
- Humans
- Hypobetalipoproteinemia, Familial, Apolipoprotein B/blood
- Hypobetalipoproteinemia, Familial, Apolipoprotein B/genetics
- Hypobetalipoproteinemia, Familial, Apolipoprotein B/metabolism
- Lipoproteins/blood
- Lipoproteins/metabolism
- Lipoproteins, IDL/blood
- Lipoproteins, IDL/metabolism
- Lipoproteins, VLDL/blood
- Lipoproteins, VLDL/metabolism
- Male
- Meals
- Middle Aged
- Models, Biological
- Mutation
- Postprandial Period
- Triglycerides/blood
- Triglycerides/metabolism
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Affiliation(s)
- Amanda J Hooper
- Department of Clinical Biochemistry (A.J.H., L.H., K.R., F.M.v.B., J.R.B.), PathWest Laboratory Medicine WA, Royal Perth Hospital, Perth WA 6000, Australia; School of Medicine and Pharmacology (A.J.H., D.C., P.H.R.B., J.R.B.), and School of Pathology and Laboratory Medicine (A.J.H., K.R.), University of Western Australia, Crawley WA 6009, Australia; Department of Radiology (J.H., S.S.), Royal Perth Hospital, Perth WA 6000, Australia; Medical Department II (K.G.P.), Grosshadern, University of Munich, 81377 Munich, Germany; and School of Surgery (F.M.v.B.), University of Western Australia, Crawley WA 6009, Australia
| | - Liesl Heeks
- Department of Clinical Biochemistry (A.J.H., L.H., K.R., F.M.v.B., J.R.B.), PathWest Laboratory Medicine WA, Royal Perth Hospital, Perth WA 6000, Australia; School of Medicine and Pharmacology (A.J.H., D.C., P.H.R.B., J.R.B.), and School of Pathology and Laboratory Medicine (A.J.H., K.R.), University of Western Australia, Crawley WA 6009, Australia; Department of Radiology (J.H., S.S.), Royal Perth Hospital, Perth WA 6000, Australia; Medical Department II (K.G.P.), Grosshadern, University of Munich, 81377 Munich, Germany; and School of Surgery (F.M.v.B.), University of Western Australia, Crawley WA 6009, Australia
| | - Ken Robertson
- Department of Clinical Biochemistry (A.J.H., L.H., K.R., F.M.v.B., J.R.B.), PathWest Laboratory Medicine WA, Royal Perth Hospital, Perth WA 6000, Australia; School of Medicine and Pharmacology (A.J.H., D.C., P.H.R.B., J.R.B.), and School of Pathology and Laboratory Medicine (A.J.H., K.R.), University of Western Australia, Crawley WA 6009, Australia; Department of Radiology (J.H., S.S.), Royal Perth Hospital, Perth WA 6000, Australia; Medical Department II (K.G.P.), Grosshadern, University of Munich, 81377 Munich, Germany; and School of Surgery (F.M.v.B.), University of Western Australia, Crawley WA 6009, Australia
| | - Danie Champain
- Department of Clinical Biochemistry (A.J.H., L.H., K.R., F.M.v.B., J.R.B.), PathWest Laboratory Medicine WA, Royal Perth Hospital, Perth WA 6000, Australia; School of Medicine and Pharmacology (A.J.H., D.C., P.H.R.B., J.R.B.), and School of Pathology and Laboratory Medicine (A.J.H., K.R.), University of Western Australia, Crawley WA 6009, Australia; Department of Radiology (J.H., S.S.), Royal Perth Hospital, Perth WA 6000, Australia; Medical Department II (K.G.P.), Grosshadern, University of Munich, 81377 Munich, Germany; and School of Surgery (F.M.v.B.), University of Western Australia, Crawley WA 6009, Australia
| | - Jianmin Hua
- Department of Clinical Biochemistry (A.J.H., L.H., K.R., F.M.v.B., J.R.B.), PathWest Laboratory Medicine WA, Royal Perth Hospital, Perth WA 6000, Australia; School of Medicine and Pharmacology (A.J.H., D.C., P.H.R.B., J.R.B.), and School of Pathology and Laboratory Medicine (A.J.H., K.R.), University of Western Australia, Crawley WA 6009, Australia; Department of Radiology (J.H., S.S.), Royal Perth Hospital, Perth WA 6000, Australia; Medical Department II (K.G.P.), Grosshadern, University of Munich, 81377 Munich, Germany; and School of Surgery (F.M.v.B.), University of Western Australia, Crawley WA 6009, Australia
| | - Swithin Song
- Department of Clinical Biochemistry (A.J.H., L.H., K.R., F.M.v.B., J.R.B.), PathWest Laboratory Medicine WA, Royal Perth Hospital, Perth WA 6000, Australia; School of Medicine and Pharmacology (A.J.H., D.C., P.H.R.B., J.R.B.), and School of Pathology and Laboratory Medicine (A.J.H., K.R.), University of Western Australia, Crawley WA 6009, Australia; Department of Radiology (J.H., S.S.), Royal Perth Hospital, Perth WA 6000, Australia; Medical Department II (K.G.P.), Grosshadern, University of Munich, 81377 Munich, Germany; and School of Surgery (F.M.v.B.), University of Western Australia, Crawley WA 6009, Australia
| | - Klaus G Parhofer
- Department of Clinical Biochemistry (A.J.H., L.H., K.R., F.M.v.B., J.R.B.), PathWest Laboratory Medicine WA, Royal Perth Hospital, Perth WA 6000, Australia; School of Medicine and Pharmacology (A.J.H., D.C., P.H.R.B., J.R.B.), and School of Pathology and Laboratory Medicine (A.J.H., K.R.), University of Western Australia, Crawley WA 6009, Australia; Department of Radiology (J.H., S.S.), Royal Perth Hospital, Perth WA 6000, Australia; Medical Department II (K.G.P.), Grosshadern, University of Munich, 81377 Munich, Germany; and School of Surgery (F.M.v.B.), University of Western Australia, Crawley WA 6009, Australia
| | - P Hugh R Barrett
- Department of Clinical Biochemistry (A.J.H., L.H., K.R., F.M.v.B., J.R.B.), PathWest Laboratory Medicine WA, Royal Perth Hospital, Perth WA 6000, Australia; School of Medicine and Pharmacology (A.J.H., D.C., P.H.R.B., J.R.B.), and School of Pathology and Laboratory Medicine (A.J.H., K.R.), University of Western Australia, Crawley WA 6009, Australia; Department of Radiology (J.H., S.S.), Royal Perth Hospital, Perth WA 6000, Australia; Medical Department II (K.G.P.), Grosshadern, University of Munich, 81377 Munich, Germany; and School of Surgery (F.M.v.B.), University of Western Australia, Crawley WA 6009, Australia
| | - Frank M van Bockxmeer
- Department of Clinical Biochemistry (A.J.H., L.H., K.R., F.M.v.B., J.R.B.), PathWest Laboratory Medicine WA, Royal Perth Hospital, Perth WA 6000, Australia; School of Medicine and Pharmacology (A.J.H., D.C., P.H.R.B., J.R.B.), and School of Pathology and Laboratory Medicine (A.J.H., K.R.), University of Western Australia, Crawley WA 6009, Australia; Department of Radiology (J.H., S.S.), Royal Perth Hospital, Perth WA 6000, Australia; Medical Department II (K.G.P.), Grosshadern, University of Munich, 81377 Munich, Germany; and School of Surgery (F.M.v.B.), University of Western Australia, Crawley WA 6009, Australia
| | - John R Burnett
- Department of Clinical Biochemistry (A.J.H., L.H., K.R., F.M.v.B., J.R.B.), PathWest Laboratory Medicine WA, Royal Perth Hospital, Perth WA 6000, Australia; School of Medicine and Pharmacology (A.J.H., D.C., P.H.R.B., J.R.B.), and School of Pathology and Laboratory Medicine (A.J.H., K.R.), University of Western Australia, Crawley WA 6009, Australia; Department of Radiology (J.H., S.S.), Royal Perth Hospital, Perth WA 6000, Australia; Medical Department II (K.G.P.), Grosshadern, University of Munich, 81377 Munich, Germany; and School of Surgery (F.M.v.B.), University of Western Australia, Crawley WA 6009, Australia
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