A nation-wide survey of patients with homozygous familial hypercholesterolemia phenotype undergoing LDL-apheresis in Turkey (A-HIT 1 registry)

Current treatments for the management of homozygous familial hypercholesterolaemia: a systematic review and commentary

AIMS

Homozygous familial hypercholesterolaemia (HoFH) is a rare disorder characterized by markedly elevated circulating low-density lipoprotein cholesterol (LDL-C) from birth. This review aimed to critically evaluate treatments for HoFH with respect to their efficacy, safety, accessibility, overall context and position within the treatment pathway.

METHODS AND RESULTS

A mixed-methods review was undertaken to systematically identify and characterize primary interventional studies on HoFH, with a focus on LDL-C reduction as the primary outcome. Interventions assessed were ezetimibe, proprotein convertase subtilisin/kexin type 9 inhibitors (PCSK9i), lomitapide, evinacumab, with or without LDL apheresis. Twenty-six seminal studies reporting unique patient data were identified. Four studies were randomized controlled trials (RCTs) with the remainder being single-arm trials or observational registries. Data extracted were heterogeneous and not suitable for meta-analyses. Two RCTs, assessed at being low risk of bias, demonstrated PCSK9i were safe and moderately effective. A randomized controlled trial (RCT) demonstrated evinacumab was safe and effective in all HoFH subgroups. Lomitapide was reported to be efficacious in a single-arm trial, but issues with adverse events, tolerability, and adherence were identified. An RCT on ezetimibe showed it was moderately effective when combined with a statin. LDL apheresis was reported as effective, but its evidence base was at very high risk of bias. All interventions lowered LDL-C, but the magnitude of this, and certainty in the supporting evidence, varied.

CONCLUSION

In practice, multiple treatments are required to treat HoFH. The sequencing of these should be made on an individualized basis, with consideration made to the benefits of each intervention.

Sex Differences in Diagnosis, Treatment, and Cardiovascular Outcomes in Homozygous Familial Hypercholesterolemia

Importance

Homozygous familial hypercholesterolemia (HoFH) is a rare genetic condition characterized by extremely increased low-density lipoprotein (LDL) cholesterol levels and premature atherosclerotic cardiovascular disease (ASCVD). Heterozygous familial hypercholesterolemia (HeFH) is more common than HoFH, and women with HeFH are diagnosed later and undertreated compared to men; it is unknown whether these sex differences also apply to HoFH.

Objective

To investigate sex differences in age at diagnosis, risk factors, lipid-lowering treatment, and ASCVD morbidity and mortality in patients with HoFH.

Design, Setting, and Participants

Sex-specific analyses for this retrospective cohort study were performed using data from the HoFH International Clinical Collaborators (HICC) registry, the largest global dataset of patients with HoFH, spanning 88 institutions across 38 countries. Patients with HoFH who were alive during or after 2010 were eligible for inclusion. Data entry occurred between February 2016 and December 2020. Data were analyzed from June 2022 to June 2023.

Main Outcomes and Measures

Comparison between women and men with HoFH regarding age at diagnosis, presence of risk factors, lipid-lowering treatment, prevalence, and onset and incidence of ASCVD morbidity (myocardial infarction [MI], aortic stenosis, and combined ASCVD outcomes) and mortality.

Results

Data from 389 women and 362 men with HoFH from 38 countries were included. Women and men had similar age at diagnosis (median [IQR], 13 [6-26] years vs 11 [5-27] years, respectively), untreated LDL cholesterol levels (mean [SD], 579 [203] vs 596 [186] mg/dL, respectively), and cardiovascular risk factor prevalence, except smoking (38 of 266 women [14.3%] vs 59 of 217 men [27.2%], respectively). Prevalence of MI was lower in women (31 of 389 [8.0%]) than men (59 of 362 [16.3%]), but age at first MI was similar (mean [SD], 39 [13] years in women vs 38 [13] years in men). Treated LDL cholesterol levels and lipid-lowering therapy were similar in both sexes, in particular statins (248 of 276 women [89.9%] vs 235 of 258 men [91.1%]) and lipoprotein apheresis (115 of 317 women [36.3%] vs 118 of 304 men [38.8%]). Sixteen years after HoFH diagnosis, women had statistically significant lower cumulative incidence of MI (5.0% in women vs 13.7% in men; subdistribution hazard ratio [SHR], 0.37; 95% CI, 0.21-0.66) and nonsignificantly lower all-cause mortality (3.0% in women vs 4.1% in men; HR, 0.76; 95% CI, 0.40-1.45) and cardiovascular mortality (2.6% in women vs 4.1% in men; SHR, 0.87; 95% CI, 0.44-1.75).

Conclusions and Relevance

In this cohort study of individuals with known HoFH, MI was higher in men compared with women yet age at diagnosis and at first ASCVD event were similar. These findings suggest that early diagnosis and treatment are important in attenuating the excessive cardiovascular risk in both sexes.

Research Progress in the Clinical Treatment of Familial Hypercholesterolemia

Familial hypercholesterolemia (FH) is an autosomal dominant inheritable disease with severe disorders of lipid metabolism. It is mainly marked by increasing levels of plasma total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C), xanthoma, corneal arch, and early-onset coronary heart disease (CHD). The prevalence of FH is high, and it is dangerous and clinically underdiagnosed. The clinical treatment for FH includes both pharmacological and non-pharmacological treatment, of which non-pharmacological treatment mainly includes therapeutic lifestyle change and dietary therapy, LDL apheresis, liver transplantation and gene therapy. In recent years, many novel drugs have been developed to treat FH more effectively. In addition, the continuous maturity of non-pharmacological treatment techniques has also brought more hope for the treatment of FH. This paper analyzes the pathogenic mechanism and the progress in clinical treatment of FH. Furthermore, it also summarizes the mechanism and structure-activity relationship of FH therapeutic drugs that have been marketed. In a word, this article provides a reference value for the research and development of FH therapeutic drugs.

Large-Scale CRISPR Screen of LDLR Pathogenic Variants

Familial hypercholesterolemia (FH) is a frequently occurring genetic disorder that is linked to early-onset cardiovascular disease. If left untreated, patients with this condition can develop severe cardiovascular complications. Unfortunately, many patients remain undiagnosed, and even when diagnosed, the treatment is often not optimal. Although mutations in the LDLR gene are the primary cause of FH, predicting whether novel variants are pathogenic is not a straightforward task. Understanding the functionality of LDLR variants is crucial in uncovering the genetic basis of FH. Our study utilized CRISPR/Cas9 cytosine base editors in pooled screens to establish a novel approach for functionally assessing tens of thousands of LDLR variants on a large scale. A total of more than 100 single guide RNAs (sgRNAs) targeting LDLR pathogenic mutations were successfully screened with relatively high accuracy. Out of these, 5 sgRNAs were further subjected to functional verification studies, including 1 in the promoter, 1 in the antisense RNA, 1 in the exon, and 2 in the intron. Except for the variant caused by the sgRNA located at intron 16, the functionalities of the other LDLR variants were all downregulated. The high similarity of LDLR intron sequences may lead to some false positives. Overall, these results confirm the reliability of the large-scale screening strategy for functional analysis of LDLR variants, and the screened candidate pathogenic mutations could be used as an auxiliary means of clinical gene detection to prevent FH-induced heart disease.

The Beneficial Effect of Lomitapide on the Cardiovascular System in LDLr-/- Mice with Obesity

OBJECTIVES

Homozygous familial hypercholesteremia (HoFH) is a rare, life-threatening metabolic disease, mainly caused by a mutation in the LDL receptor. If untreated, HoFH causes premature death from acute coronary syndrome. Lomitapide is approved by the FDA as a therapy to lower lipid levels in adult patients with HoFH. Nevertheless, the beneficial effect of lomitapide in HoFH models remains to be defined. In this study, we investigated the effect of lomitapide on cardiovascular function using LDL receptor-knockout mice (LDLr-/-).

METHODS

Six-week-old LDLr-/- mice were fed a standard diet (SD) or a high-fat diet (HFD) for 12 weeks. Lomitapide (1 mg/Kg/Day) was given by oral gavage for the last 2 weeks in the HFD group. Body weight and composition, lipid profile, blood glucose, and atherosclerotic plaques were measured. Vascular reactivity and markers for endothelial function were determined in conductance arteries (thoracic aorta) and resistance arteries (mesenteric resistance arteries (MRA)). Cytokine levels were measured by using the Mesoscale discovery V-Plex assays.

RESULTS

Body weight (47.5 ± 1.5 vs. 40.3 ± 1.8 g), % of fat mass (41.6 ± 1.9% vs. 31.8 ± 1.7%), blood glucose (215.5 ± 21.9 vs. 142.3 ± 7.7 mg/dL), and lipid levels (cholesterol: 600.9 ± 23.6 vs. 451.7 ± 33.4 mg/dL; LDL/VLDL: 250.6 ± 28.9 vs. 161.1 ± 12.24 mg/dL; TG: 299.5 ± 24.1 vs. 194.1 ± 28.1 mg/dL) were significantly decreased, and the % of lean mass (56.5 ± 1.8% vs. 65.2 ± 2.1%) was significantly increased in the HFD group after lomitapide treatment. The atherosclerotic plaque area also decreased in the thoracic aorta (7.9 ± 0.5% vs. 5.7 ± 0.1%). After treatment with lomitapide, the endothelium function of the thoracic aorta (47.7 ± 6.3% vs. 80.7 ± 3.1%) and mesenteric resistance artery (66.4 ± 4.3% vs. 79.5 ± 4.6%) was improved in the group of LDLr-/- mice on HFD. This was correlated with diminished vascular endoplasmic (ER) reticulum stress, oxidative stress, and inflammation.

CONCLUSIONS

Treatment with lomitapide improves cardiovascular function and lipid profile and reduces body weight and inflammatory markers in LDLr-/- mice on HFD.

2023 Update on European Atherosclerosis Society Consensus Statement on Homozygous Familial Hypercholesterolaemia: new treatments and clinical guidance

This 2023 statement updates clinical guidance for homozygous familial hypercholesterolaemia (HoFH), explains the genetic complexity, and provides pragmatic recommendations to address inequities in HoFH care worldwide. Key strengths include updated criteria for the clinical diagnosis of HoFH and the recommendation to prioritize phenotypic features over genotype. Thus, a low-density lipoprotein cholesterol (LDL-C) >10 mmol/L (>400 mg/dL) is suggestive of HoFH and warrants further evaluation. The statement also provides state-of-the art discussion and guidance to clinicians for interpreting the results of genetic testing and for family planning and pregnancy. Therapeutic decisions are based on the LDL-C level. Combination LDL-C-lowering therapy-both pharmacologic intervention and lipoprotein apheresis (LA)-is foundational. Addition of novel, efficacious therapies (i.e. inhibitors of proprotein convertase subtilisin/kexin type 9, followed by evinacumab and/or lomitapide) offers potential to attain LDL-C goal or reduce the need for LA. To improve HoFH care around the world, the statement recommends the creation of national screening programmes, education to improve awareness, and management guidelines that account for the local realities of care, including access to specialist centres, treatments, and cost. This updated statement provides guidance that is crucial to early diagnosis, better care, and improved cardiovascular health for patients with HoFH worldwide.

Case report: Therapy adherence, MTTP variants, and course of atheroma in two patients with HoFH on low-dose, long-term lomitapide therapy

Background: Homozygous familial hypercholesterolemia (HoFH) is a rare and devastating genetic condition characterized by extremely elevated levels of low-density lipoprotein cholesterol (LDL-C) leading to an increased risk of premature atherosclerosis. Patients with Homozygous familial hypercholesterolemia mostly present with mutations in LDLR; however, herein, we present two cases with concomitant microsomal triglyceride transfer protein mutations, who showed different clinical courses and treatment adherence on long-term therapy with the new MTTP inhibitor lomitapide. Objectives: We aimed to present the possibility of preventing the progression of atherosclerotic burden with effective and safe LDL-C reduction in patients with Homozygous familial hypercholesterolemia on low-dose lomitapide therapy and emphasize the role of treatment adherence in therapy success. Methods: We present two patients with phenotypically Homozygous familial hypercholesterolemia, a compound heterozygous woman and a simple homozygous man, both with LDLR and additional MTTP mutations, who were treated with the MTTP-inhibiting agent lomitapide, with different treatment compliances. The role of impulsivity was investigated through Barratt Impulsivity Scale 11, and the extent of the atherosclerotic burden was followed up using coronary artery calcium scoring, echocardiographic and sonographic findings, and, eventually, through a strict follow-up of laboratory parameters. The patients were on lomitapide for 8 and 5 years, respectively, with no adverse effects. Conclusion: When accompanied by good adherence to therapy, low-dose lomitapide on top of standard lipid-lowering therapy with decreased frequency of lipid apheresis prevented the progression of atherosclerotic burden. Non-compliance might occur due to patient impulsivity and non-adherence to a low-fat diet.

Current Treatment Options in Homozygous Familial Hypercholesterolemia

Homozygous familial hypercholesterolemia (HoFH) is the rare form of familial hypercholesterolemia causing extremely high low-density lipoprotein cholesterol (LDL-C) levels, leading to atherosclerotic cardiovascular disease (ASCVD) in the first decades of life, if left untreated. Early diagnosis and effective lipid lowering therapy (LLT) are crucial for the prevention of early ASCVD in patients with HoFH. On-treatment LDL-C levels are the best predictor of survival. However, due to the absent or defective LDL-receptor activity, most individuals with HoFH are resistant to conventional LLT, that leads to LDL-C clearance by upregulating LDL-receptors. We are at the dawn of a new era of effective pharmacotherapies for HoFH patients, with new agents providing an LDL-receptor independent cholesterol reduction. In this context, the present review provides a summary of the currently available therapies and emerging therapeutic agents for the management of patients with HoFH, in light of recent evidence and guideline recommendations.

Aortic stenosis in homozygous familial hypercholesterolaemia: a paradigm shift over a century

AIMS

Homozygous familial hypercholesterolaemia (HoFH) is an orphan disease defined by extreme elevations in low-density lipoprotein cholesterol, cutaneous xanthomas, and pre-mature atherosclerotic cardiovascular disease. Survival has more than doubled over the past three decades. Aortic stenosis (AS) [supravalvular aortic stenosis (SVAS) or valvular aortic stenosis (VAS)] is commonly encountered. There are no medical treatments available and complex high-risk surgeries represent the only available option in severe cases. A systematic review was performed to summarize the current evidence on AS in HoFH and to determine whether pharmacological treatment (statins) have had an impact on clinical presentation, phenotype and clinical course over the past nine decades (PROSPERO CRD42021250565).

METHODS AND RESULTS

MEDLINE, Embase Classic + Embase, Cochrane Central Register of Controlled Trials, PubMed, AfricaWide, and Scopus were searched from inception to 10 November 2021. Searches identified 381 publications, of which 19 were retained; they were cross-sectional or retrospective studies. Separately, 108 individual case reports were described. Within the 424 HoFH cases, AS was identified in 57% of patients in the pre-statin era vs. 35% in patients reported more recently (>2000, long-term statin period). With an increase in longevity due to statins and lipoprotein apheresis, a change in the proportion of patients with SVAS and VAS with a SVAS:VAS ratio of 47:53 and 10:90 for HoFH patients not on statin and on long-term statin, respectively, was noted.

CONCLUSION

These data suggest that SVAS and VAS are frequent in HoFH and that the phenotype has shifted towards calcific VAS as statins and lipoprotein apheresis improve survival in these patients.

Is Liver Transplant Curative in Homozygous Familial Hypercholesterolemia? A Review of Nine Global Cases

INTRODUCTION

Homozygous familial hypercholesterolemia (HoFH) is a rare, life-threatening, inherited condition characterized by extremely elevated levels of low-density lipoprotein cholesterol (LDL-C). Patients are at high risk of atherosclerotic cardiovascular disease, adverse cardiovascular events, and associated early mortality. Liver transplant is sometimes used with curative intent. The objective of the current case series was to evaluate the follow-up of a range of patients who have undergone liver transplant for the treatment of HoFH.

METHODS

Patients with clinical and/or genetic diagnoses of HoFH were treated according to local practices in four units in Europe and the Middle East. All patients underwent liver transplantation. Baseline and long-term follow-up data were collected, including LDL-C levels, DNA mutations, lipid-lowering medications, and complications due to surgery and immunosuppressive therapy.

RESULTS

Nine patients were included with up to 22 years' follow-up (mean ± SD 11.7 ± 11.7 years; range 0.5-28 years). Three of the patients died as a result of complications of transplant surgery (mortality rate 33%). Among the surviving six patients, four required continued lipid-lowering therapy (LLT) to maintain LDL-C levels and two patients show signs of increasing LDL-C levels that require management. One case (11%) required two consecutive transplants to achieve a viable graft and is awaiting a third transplant because of graft failure.

CONCLUSIONS

Liver transplant did not enable attainment of recommended LDL-C targets in most patients with HoFH, and the majority of patients still required post-transplant LLT. Liver transplant was not curative in most of the patients with HoFH followed. Guidelines suggest that transplant is a treatment of last resort if contemporary treatments are not available or possible.

Familial Hypercholesterolemia (FH) Registry Worldwide: A Systematic Review

Familial hypercholesterolemia (FH) is the most common genetic disease which accelerates the development of premature coronary artery disease (CAD) in young adults if remains untreated. The overall prevalence of FH is currently unknown and is usually underdiagnosed and undertreated worldwide. FH registry in different geographical area is a mission that helps early diagnosis of FH patients in the general population. PubMed, ISI Web of Science, Scopus, and Google Scholar were searched systematically for studies and reports on the FH registry using related keywords. Finally, 27 studies were included in this review. Most of the studies used the CASCADE screening method based on 1 or more than 1 of the 3 well-established FH criteria namely, the Dutch Lipid Clinic Network, Simon Broome Register, or Make Early Diagnosis to Prevent Early Death criteria. Except for a small number of studies that the genetic and molecular methods were used, in other studies only clinical diagnosis was applied. All these studies claimed that the FH registry causes the identification of many new cases as a result of used CASCADE screening and referral to lipid clinics. They concluded that the FH registry increases general and also physician awareness on FH prevalence and its related complications which in the long-term will improve FH management. This indicates that in other parts of the world, the FH registry should be established as well so that more accurate statistics on the prevalence of this disease can be found worldwide which would help in diagnosis and prevention.

Familial Hypercholesterolemia: Global Burden and Approaches

PURPOSE OF REVIEW

Familial hypercholesterolemia (FH) is the most common genetic metabolic disorder characterized by markedly elevated LDL-C levels from birth leading to atherosclerotic cardiovascular disease (ASCVD) and premature deaths. The purpose of this review is to share the current knowledge in the diagnosis, risk estimation, and management of patients with FH in the light of recent evidence and guideline recommendations.

RECENT FINDINGS

Recent registries underscored the prevalence of FH as 1/200-250 translating to an almost 1500 million subjects suffering from FH worldwide. However, only a minority of FH patients are identified early and effectively treated. In most cases, mutations in the LDL-receptor (LDLR) gene and to a lesser degree in the apolipoprotein B-100 (APOB), proprotein convertase subtilisin/kexin type 9 (PCSK9), and the LDL-receptor adaptor protein 1 (LDLRAP1) genes cause FH. Diagnostic scores such as Dutch Lipid Clinic Network criteria using clinical manifestations are helpful in identifying FH. Traditional risk factors and high lipoprotein(a) affect the course of the disease. Vascular ultrasound imaging and coronary calcium scoring are helpful for further risk estimation of these patients. Getting to LDL-C goals is possible with currently available treatments including statins, ezetimibe, and PCSK9 inhibitors, as well as lipoprotein apheresis, lomitapide, and mipomersen in more severe phenotypes. Additionally, novel agents bempedoic acid, inclisiran, and evinacumab expanded the treatment choices for some patients with FH. Early diagnosis and initiation of LDL-C lowering are still required to achieve the greatest reduction in ASCVD morbidity and mortality in patients with FH. FH is a common genetic disorder characterized by markedly elevated LDL-C levels from birth onward, resulting in significantly increased risk for ASCVD. Despite major advances in our understanding of the disease and effective therapies, FH is still underdiagnosed and undertreated. Early initiation of LDL-C lowering by increased awareness of FH among the healthcare professionals, patients, and the public is necessary to achieve meaningful reduction in ASCVD morbidity and mortality in these patients.

Management of LDL-cholesterol levels in patients with Diabetes Mellitus in Cardiology Practice: Real-life evidence of Under-treatment from the EPHESUS registry

BACKGROUND AND AIMS

Effective treatment of high low-density lipoprotein cholesterol (LDL-C) levels has been shown to improve cardiovascular outcomes of patients with diabetes mellitus (DM). Herein, we aimed to provide insight to the real-life management of patients with DM in terms of LDL-C goal attainment and adherence to lipid management recommendations. Our objective was also to reveal the reasons of poor LDL-C goal attainment by assessing the perceptions of both physicians and patients.

METHODS

We compared the diabetic and non-diabetic patients from the database of a nationwide registry conducted in cardiology outpatient clinics with regard to the demographic characteristics, educational status, comorbidities, medications, laboratory parameters and LDL-C goal attainment. Also, both the patients and attending physicians were surveyed to analyse perceptions and awareness of hypercholesterolemia.

RESULTS

Of the 1868 consecutively enrolled patients, 873 (47%) had DM. Proportion of patients on statins was significantly lower in patients with DM (67.8% vs 55.3%; P < .001). The proportion of patients who attained LDL-C targets were lower among the diabetic patients (17.8% vs 15%; P = .06). The most common causes of the discontinuation of statin therapy were negative media coverage about statins (32.1%), and recommendations of physicians to stop the lipid lowering therapy (29.6%). Analysis of the physician survey revealed that the physicians could determine the off-target patients accurately (negative predictive value 98.4%) while the positive predictive value (48.8%) was low. The reasons for not attaining the LDL-C goals in diabetic patients were not prescription of statins (38%) and inadequate (eg low-dose, non-adherent) statin (28.3%) dosages.

CONCLUSIONS

In real-life clinical cardiology practice, diabetic patients are far below the recommended LDL-C treatment goals. High-intensity statin treatment in diabetic population is still avoided because of the concerns about polypharmacy and drug interactions. Also, the inertia of physicians and even cardiologists is probably a major cause of refraining of prescription of optimal statin dosages.

The landscape of preventive cardiology in Turkey: Challenges and successes

Turkey, like many countries, is facing a growing burden of non-communicable disease (NCD)s and is among the countries with high cardiovascular mortality in Europe. Moreover, Turkey currently has the highest rate of premature cardiovascular disease (CVD) in Europe. During the last decades, Turkey made fundamental reforms in the health system to improve the treatment of risk factors to prevent CVD. The most outstanding success was in the area of tobacco control (13.4% decrease in smoking prevalence) and decreasing the salt consumption of the population (from 18 to 9.9 g/day) leading to a significant decrease in CVD mortality from 45% to 36.8% of all deaths. However, obesity and diabetes are increasing rapidly as a result of urbanization, low physical activity and unhealthy eating and the new generation is starting to take up smoking. The increase in cardiometabolic risk factors and aging of the population are expected to increase the number of CVD deaths. All CVD risk factors except smoking are significantly more prevalent in women. In addition, rare disease is a country specific problem with a significant contribution to the high rates of premature CVD in Turkey. Despite major improvements in management in acute coronary syndromes, sustained achievement in guideline recommended goals is suboptimal. In patients with a previous cardiovascular event smoking rate is 25.5%, 80.9% of these patients are overweight (BMI ≥25 kg/m²), 30% obese (BMI ≥30 kg/m²), and LDL‐cholesterol targets of 70 mg/dL are attained in only 18%. Herein, we scrutinize the achievements and challenges of Turkey in establishing a ‘National Heart Health Policy’ aiming to decrease the burden of CVD and its risk factors.

LDL Apheresis and Lp (a) Apheresis: A Clinician's Perspective

PURPOSE OF REVIEW

Lipoprotein apheresis is the most effective means of lipid-lowering therapy. However, it's a semi-invasive, time consuming, and chronic therapy with variable adherence. There are still no specific guideline recommendations for the management of patients on lipid apheresis. The purpose of this review is to discuss the clinical indications and major drawbacks of lipid apheresis in the light of recent evidence.

RECENT FINDINGS

Lipoprotein apheresis should be initiated at early ages and performed frequently to receive the expected cardiovascular benefits. However, in clinical practice, most patients experience ineffective apheresis and fail to reach lipid targets. This real-world failure is due to several factors including late diagnosis, delayed referral, and improper frequency of procedures. All these denote that awareness is still low among physicians. Another important factor is the semi-invasive, time consuming nature of the apheresis, leading to high refusal and low adherence rates. Moreover, apheresis decreases quality of life and increases the risk of depression. Mental status is also deteriorated in patients with familial hypercholesterolemia on lipid apheresis. New effective lipid lowering agents are underway with promising cardiovascular results. To overcome the drawbacks, a structured approach, including standardized protocols for lipoprotein apheresis with regular cardiovascular follow-up is warranted. New effective lipid lowering agents with documented cardiovascular benefit, should be integrated into the treatment algorithms of patients on lipoprotein apheresis.

How registers could enhance knowledge and characterization of genetic dyslipidaemias: The experience of the LIPIGEN in Italy and of other networks for familial hypercholesterolemia

Familial hypercholesterolemia (FH) is a common genetic disorder of lipid metabolism, still underdiagnosed and undertreated in the general population. Pathology registers could play a crucial role in the creation of a comprehensive and integrated global approach to cover all aspects of this disease. Systematic data collection of patients affected by FH has increased dramatically worldwide in the past few years. Moreover, results from registers already established for the longest time showed their potentialities in the implementation of the knowledge of FH, comparing country-specific approaches and providing real-world data about identification, management and treatment of FH individuals in the clinical practice. The potential fields of research through registers are related to the deepening of the genetic basis of disease, the study of genotype-phenotype correlation, the local adaption and implementation of diagnostic algorithms, the comparison of pharmacological approaches and treatment gaps in real-life clinical practice, the evaluation of specific subpopulations, and the identification of factors modifying cardiovascular disease risk. Registers could become also a valid resource for other rare dyslipidaemias, contributing towards the evidence-based enhancement in the worldwide care of uncommon diseases.

Negative impact of COVID-19 pandemic on the lifestyle and management of patients with homozygous familial hypercholesterolemia

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Patients with homozygous familial hypercholesterolemia (HoFH) have increased cardiovascular risk.

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Coronavirus disease 2019 (COVID-19) pandemic affected healthy life behaviors and anxiety of patients with HoFH.

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Fear of COVID-19 leads to avoidance of seeking medical care.

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As a hospital-based treatment, lipid apheresis is disrupted during the pandemic.

Lomitapide for treatment of homozygous familial hypercholesterolemia: The Québec experience

BACKGROUND AND AIMS

Homozygous familial hypercholesterolemia (HoFH) is an orphan disease, most often caused by bi-allelic mutations of the LDLR gene. Patients with HoFH have elevated LDL-C levels >13 mmol/L, tendinous xanthomata and severe, premature atherosclerotic cardiovascular disease (ASCVD). Untreated, most HoFH patients die of ASCVD in youth. New therapeutic modalities include lomitapide, an inhibitor of microsomal triglyceride transfer protein that lowers hepatic LDL-C production. We have recently identified 79 Canadian patients with HoFH. Here, we describe our experience with lomitapide in the province of Quebec, a geographic area known to have a high prevalence of HoFH.

METHODS

This is a retrospective case series of 12 HoFH patients followed at three lipidology centers in the province of Quebec.

RESULTS

Mean age of the patients was 44 ± 18 years; age at time of HoFH diagnosis ranged from 2 to 59 years. All patients were on a statin and ezetimibe 10 mg/day and five patients were treated with LDL apheresis. Treatment with lomitapide reduced LDL-C levels by 38% (intention-to-treat). Intolerable gastrointestinal side effects were observed in 3/12 patients and were the main reason for treatment discontinuation. Three patients tolerated lomitapide at doses ranging between 5 and 30 mg/day without major side effects. Downwards drug titration was necessary in the 6 remaining patients because of gastrointestinal side effects (n = 5) and elevated liver enzymes (n = 1), and 2 of them finally discontinued treatment.

CONCLUSIONS

Lomitapide may be used to further decrease LDL-C in HoFH patients; gastrointestinal side effects and hepatic toxicity may limit adherence.

Evidence for improved survival with treatment of homozygous familial hypercholesterolemia

PURPOSE OF REVIEW

Homozygous familial hypercholesterolemia (HoFH) is an orphan disease caused by biallelic mutations at the LDL receptor (LDLR) gene, with a prevalence estimated at 1 : 250 000 to 1 : 630 000. HoFH is characterized by extremely elevated plasma levels of LDL-C greater than 10 mmol/l (>387 mg/dl), tendinous and cutaneous xanthomas in youth and premature atherosclerotic cardiovascular disease (ASCVD). The expected prevalence varies from country to country depending on the presence of founder effects, genetic probability and life expectancy. Untreated, HoFH is a fatal condition before age 30. Plasma levels of LDL-C are the major cause of mortality and the therapeutic target. Statin therapy led to a remarkable improvement in survival but is of limited use in loss-of-function LDLR gene variants or 'null' mutations. Inhibitors of PCSK9 are a useful adjunct in patients with LDLR mutations with residual activity. Extracorporeal LDL filtration has improved survival since its introduction three decades ago.

RECENT FINDINGS

Novel therapies, not dependent on a functioning LDLR include lomitapide and mipomersen, which decrease hepatic apolipoprotein B secretion, and evinacumab, directed at the angiopoietin like-3 protein (ANGPLT-3).

SUMMARY

Over the past 3-4 decades, the survival of patients with HoFH has increased markedly. New therapeutic options offer new hope.

Lomitapide-a Microsomal Triglyceride Transfer Protein Inhibitor for Homozygous Familial Hypercholesterolemia

PURPOSE OF REVIEW

Homozygous familial hypercholesterolemia (HoFH) is a rare, genetic condition characterized by high levels of Low density lipoprotein cholesterol (LDL-C); overt, early-onset atherosclerotic cardiovascular disease (ASCVD); and premature cardiovascular events and mortality. Lomitapide is a first-in-class microsomal triglyceride transfer protein inhibitor for the treatment of HoFH. This review provides an update on data emerging from real-world studies of lomitapide following on from its pivotal phase 3 clinical trial in HoFH.

RECENT FINDINGS

Recent registry data have confirmed that HoFH is characterized by delayed diagnosis, with many patients not receiving effective therapy until they are approaching the age when major adverse cardiovascular events may occur. Data from case series of varying sizes, and from a 163-patient registry of HoFH patients receiving lomitapide, have demonstrated that lomitapide doses are lower and adverse events less severe than in the phase 3 study. Lomitapide enables many patients to reach European Atherosclerosis Society LDL-C targets. Some patients are able to reduce frequency of lipoprotein apheresis or, in some cases, stop the procedure altogether-unless there is significant elevation of lipoprotein (a). Modelling analyses based on historical and clinical trial data indicate that lomitapide has the potential to improve cardiovascular outcomes and survival in HoFH. Real-world clinical experience with lomitapide has shown the drug to be effective with manageable, less marked adverse events than in formal clinical studies. Event modelling data suggest a survival benefit with lomitapide in HoFH.

Mental status and physical activity in patients with homozygous familial hypercholesterolemia: A subgroup analysis of a nationwide survey (A-HIT1 registry)

BACKGROUND

Homozygous familial hypercholesterolemia (HoFH) is a rare, life-threatening disease due to high serum low-density lipoprotein (LDL) cholesterol levels. LDL cholesterol-lowering interventions are fundamental for patients with HoFH.

OBJECTIVE

It was aimed to investigate the association between the mental status of patients with HoFH and healthy lifestyle behaviors.

METHODS

This subgroup analysis of the A-HIT1 population included the data of patients aged ≥18 years with a clinical diagnosis of HoFH undergoing therapeutic LDL apheresis. Besides the demographic and clinical characteristics of patients, healthy lifestyle behaviors were assessed, and psychiatric symptoms were screened by Symptom Check List (SCL-90-R).

RESULTS

The highest percentage for pathology was observed in dimensions of obsessive-compulsive, somatization, interpersonal sensitivity, and depression in SCL-90-R. Patients with any cardiovascular condition have more psychiatric symptoms in different fields of SCL-90-R. The outcomes of the correlative analysis indicated that lower the age of the first coronary event better the psychiatric status, probably denoting a better adaptation to disease and its treatment. Among 68 patients, 36 patients were not exercising regularly. Patients with regular physical activity had significantly lower scores in most dimensions of SCL-90-R and there was no association between regular physical activity and other investigated variables. The strongest predictor of regular exercising was global severity index of SCL-90-R.

CONCLUSION

In the HoFH population, there was a high prevalence of mental disturbances. Better psychiatric status was associated with regular exercising. Therefore, assessing the mental status of patients with HoFH and referring patients in need, to a psychiatrist, may improve the outcome of patients.

What have we learned from Turkish familial hypercholesterolemia registries (A-HIT1 and A-HIT2)?

BACKGROUND AND AIMS

Familial hypercholesterolemia (FH) is a common genetic disease of high-level cholesterol leading to premature atherosclerosis. One of the key aspects to overcome FH burden is the generation of large-scale reliable data in terms of registries. This manuscript underlines the important results of nation-wide Turkish FH registries (A-HIT1 and A-HIT2).

METHODS

A-HIT1 is a survey of homozygous FH patients undergoing low density lipoprotein (LDL) apheresis (LA). A-HIT2 is a registry of adult FH patients (homozygous and heterozygous) admitted to outpatient clinics. Both registries used clinical diagnosis of FH.

RESULTS

A-HIT1 evaluated 88 patients (27 ± 11 years, 41 women) in 19 centers. All patients were receiving regular LA. There was a 7.37 ± 7.1-year delay between diagnosis and initiation of LA. LDL-cholesterol levels reached the target only in 5 cases. Mean frequency of apheresis sessions was 19 ± 13 days. None of the centers had a standardized approach for LA. Mean frequency of apheresis sessions was every 19 ± 13 (7-90) days. Only 2 centers were aware of the target LDL levels. A-HIT2 enrolled 1071 FH patients (53 ± 8 years, 606 women) from 31 outpatients clinics specialized in cardiology (27), internal medicine (1), and endocrinology (3); 96.4% were heterozygous. 459 patients were on statin treatment. LDL targets were attained in 23 patients (2.1% of the whole population, 5% receiving statin) on treatment. However, 66% of statin-receiving patients were on intense doses of statins. Awareness of FH was 9.5% in the whole patient population.

CONCLUSIONS

The first nationwide FH registries revealed that FH is still undertreated even in specialized centers in Turkey. Additional effective treatment regiments are urgently needed.

Familial Hypercholesterolemia and Lipoprotein Apheresis

Lipoprotein apheresis has been developed as the treatment for refractory familial hypercholesterolemia (FH) to remove low-density lipoprotein (LDL), which is the main pathogenic factor. Currently, three procedures are available in Japan, including the plasma exchange, double-membrane filtration, and selective LDL adsorption. Selective LDL adsorption, which was developed in Japan, has been one of the most common treatment methods in the world. Lipoprotein apheresis enabled the prevention of atherosclerosis progression even in homozygous FH (HoFH) patients. However, in our observational study, HoFH patients who started lipoprotein apheresis in adulthood had a poorer prognosis than those who started in childhood. Therefore, HoFH patients need to start lipoprotein apheresis as early as possible. Although the indication for lipoprotein apheresis in heterozygous FH (HeFH) patients has been decreasing with the advent of strong statins, our observational study showed that HeFH patients who discontinued lipoprotein apheresis had a poorer prognosis than patients who continued apheresis therapy. These results suggest that it is beneficial for very-high-risk HeFH patients to be treated by lipoprotein apheresis even if their LDL cholesterol is controlled well by lipid-lowering agents. Since launching a new class of lipid-lowering agents, proprotein convertase subtilisin/kexin type 9 (PCSK9) antibody and microsome triglyceride transfer protein inhibitors, the indication for lipoprotein apheresis in FH has been changing. However, despite the development of these drugs, lipoprotein apheresis is still an option with a high therapeutic effect for FH patients with severe atherosclerotic cardiovascular disease.

Overview of the current status of familial hypercholesterolaemia care in over 60 countries - The EAS Familial Hypercholesterolaemia Studies Collaboration (FHSC)

BACKGROUND AND AIMS

Management of familial hypercholesterolaemia (FH) may vary across different settings due to factors related to population characteristics, practice, resources and/or policies. We conducted a survey among the worldwide network of EAS FHSC Lead Investigators to provide an overview of FH status in different countries.

METHODS

Lead Investigators from countries formally involved in the EAS FHSC by mid-May 2018 were invited to provide a brief report on FH status in their countries, including available information, programmes, initiatives, and management.

RESULTS

63 countries provided reports. Data on FH prevalence are lacking in most countries. Where available, data tend to align with recent estimates, suggesting a higher frequency than that traditionally considered. Low rates of FH detection are reported across all regions. National registries and education programmes to improve FH awareness/knowledge are a recognised priority, but funding is often lacking. In most countries, diagnosis primarily relies on the Dutch Lipid Clinics Network criteria. Although available in many countries, genetic testing is not widely implemented (frequent cost issues). There are only a few national official government programmes for FH. Under-treatment is an issue. FH therapy is not universally reimbursed. PCSK9-inhibitors are available in ∼2/3 countries. Lipoprotein-apheresis is offered in ∼60% countries, although access is limited.

CONCLUSIONS

FH is a recognised public health concern. Management varies widely across countries, with overall suboptimal identification and under-treatment. Efforts and initiatives to improve FH knowledge and management are underway, including development of national registries, but support, particularly from health authorities, and better funding are greatly needed.