Applying an LDL-C threshold-based approach to identify individuals with familial hypercholesterolemia

Lipid Control and Medical Costs Among Patients With and Without Established Atherosclerotic Cardiovascular Disease Followed in a Brazilian Private Healthcare System

Background

There is limited real-world data of lipid control and healthcare costs among patients with and without Atherosclerotic Cardiovascular Disease (ASCVD) in Latin America.

Methods

A retrospective cohort study including patients with LDL-cholesterol (LDL-C) assessment from 2015 to 2017 was performed in a health insurance database. Patient characteristics, comorbidities and laboratory data were collected, and International Classification of Diseases (ICD) codes were used to identify a subcohort of patients with ASCVD (secondary prevention) and assess the proportion of these patients with LDL-C controlled. Lipid control among patients without ASCVD (primary prevention) and healthcare costs in one year in the overall population were also assessed.

Results

From the 17,434 patients selected, 5,208 (29.8%) had ASCVD. The mean age of these patients in secondary prevention was 68.9 (±12.3) years and 47.8% were male patients. LDL-C < 70 mg/dL was identified in 19.1% of the ASCVD population and only 4.1% had an LDL-C < 50 mg/dL. LDL control was worse in women compared to men (13.1% vs. 25.7%; P < 0.01). The average cost in one year was 3,591 American dollars (USD) per patient in primary prevention compared to 8,210 dollars per year for patients in secondary prevention (P < 0.01). While outpatient costs accounted for 59.8% of the total cost in the primary prevention group, the main cost of the secondary prevention population was related to hospital costs (54.1%).

Conclusion

Despite the favorable evidence for intensive cholesterol reduction, the evaluation of large real-world database with more than 17,000 individuals showed that the targets of guideline recommendations have not yet been adequately incorporated into clinical practice. Average annual cost per patient in secondary prevention is more than twice compared to primary prevention. Hospital expenses account for most of the cost in the secondary prevention group, while outpatient costs predominate in primary prevention.

Screening and clinical characteristics analysis of familial hypercholesterolemia in a tertiary public hospital

Background and aims

Familial hypercholesterolemia (FH) is becoming a global burden. However, it remains underdiagnosed and undertreated worldwide. This study aimed to observe the screening rate of FH patients and department distribution among hospitalized patients using different diagnostic criteria.

Methods

A total of 45,410 inpatients with LDL-C ≥3.5 mmol/L between 2008 and 2019 were included from The Second Affiliated Hospital of Nanchang University. Inpatients are diagnosed and divided into groups by Dutch Lipid Clinic Network (DLCN) criteria, Chinese-modified DLCN criteria and Chinese expert consensus (CEC) criteria.

Results

There were 172, 1,076 and 115 inpatients included in the DLCN group, Chinese-modified DLCN group and CEC group, respectively (screening rates: 0.38%, 2.37% and 0.25%). These FH patients had a very high risk of atherosclerotic cardiovascular disease (ASCVD) (55.7%-74.4%), especially in the DLCN group and CEC group (70.4%-74.4%). More than half of the patients were in the Department of Cardiology, and other high-risk departments included Neurology, Nephrology, Vascular Surgery, Otolaryngology & Head Neck Surgery and Traditional Chinese Medicine (24.35%-31.51%). Overall, hypertension, coronary heart disease, carotid arteriosclerosis, hepatic cyst, arrhythmia, and nonalcoholic fatty liver disease were common accompanying diseases with FH.

Conclusions

It is necessary to establish appropriate diagnostic criteria and more positive treatment strategies for the FH inpatient population. In addition, promoting awareness of FH among doctors from other departments is also necessary. Therefore, developing a comprehensive management strategy for FH disease is very important.

Gene and cell therapy approaches for familial hypercholesterolemia: An update

Familial hypercholesterolemia (FH) is a common autosomal codominant hereditary illness marked by the heightened risk of early atherosclerotic cardiovascular disease and high blood levels of low-density lipoprotein cholesterol (LDL-C). FH patients can have homozygous or heterozygous variants. This condition has been linked to variations in the genes for the LDL receptor (LDLR), apolipoprotein B, proprotein convertase subtilisin/Kexin 9 (PCSK9), and LDLR adaptor protein 1. Drugs such as statins, ezetimibe, and PCSK9 inhibitors are currently widely available, allowing for the theoretical normalization of plasma LDL-C levels mostly in patients with heterozygous FH. However, homozygous FH patients usually have a poor response to traditional lipid-lowering therapy and may have a poor prognosis at a young age. LDL apheresis and novel pharmacological therapies such as microsomal transfer protein inhibitors or anti-angiopoietin-like protein 3 monoclonal antibodies are extremely expensive and unavailable in most regions of the world. Therefore, the unmet need persists for these patients. In this review, we discuss the numerous gene delivery, gene editing, and stem cell manipulation techniques used in this study to correct FH-causing LDLR gene variations in vitro, ex vivo, and in vivo. Finally, we looked at a variety of studies that corrected genetic defects that caused FH using the ground-breaking clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) gene editing technology.

Serum Low Density Lipoprotein Cholesterol Concentration Is Not Dependent on Cholesterol Synthesis and Absorption in Healthy Humans

Introduction. Pharmacological reduction of cholesterol (C) synthesis and C absorption lowers serum low-density lipoprotein C (LDL-C) concentrations. We questioned whether high baseline C synthesis or C absorption translates into high serum LDL-C concentrations or if there was no connection. Therefore, we studied the association between serum LDL-C and C synthesis or C absorption in healthy subjects. Methods. Three published data sets of young subjects on different diets (study 1), mildly hypercholesterolemic subjects without cardiovascular disease (study 2) and healthy controls of the Framingham study (study 3) were used. The three study populations varied in sex, age, and weight. C synthesis and C fractional absorption rate (FAR) were measured with fecal sterol balance and stable isotope techniques (studies 1 and 2). Additionally, serum lathosterol and campesterol concentrations corrected for the serum total C concentration (R_lathosterol and R_campesterol) were used as markers for hepatic C synthesis and C FAR, respectively (studies 1−3). Linear regression analysis was applied to evaluate associations between LDL-C, C synthesis, and C absorption. Results. Seventy-three, 37, and 175 subjects were included in studies 1, 2, and 3, respectively. No statistically significant associations were found between LDL-C and the measured C synthesis and C FAR, nor for R_lathosterol and R_campesterol in any of the study groups. This lack of associations was confirmed by comparing the male subjects of studies 1 and 2. Study 1 subjects had a 50% lower serum LDL-C than the study 2 subjects (p < 0.01), but not a lower C synthesis, C FAR, R-lathosterol, or R_campesterol. Conclusions. Under physiological conditions, C synthesis and C FAR are not major determinants of circulating serum LDL-C concentrations in healthy subjects. The results need to be confirmed in large-scale studies in healthy subjects and patients at risk for cardiovascular disease.

A mixed methods study of the awareness and management of familial hypercholesterolaemia in Irish general practice

Introduction

Familial Hypercholesterolemia (FH) is one of the most common genetic disorders, with an estimated global prevalence of 1:200-500, which leads to premature cardiovascular disease. Nevertheless, public and professional awareness of FH is often lacking, with an estimated 20,000 largely undiagnosed cases in Ireland.

Purpose

The overall aim of the project was to test the feasibility of a model of care that would include electronic record screening, clinical assessment, and coding of possible FH patients across a network of general practices in Ireland. In addition, a secondary aim was to gauge the awareness and knowledge of FH across the network.

Methods

This study took part in multiple phases, employing a mixed methods design. The study included a validated questionnaire, tailored online educational resources, a retrospective chart review of patients with a history of elevated LDL cholesterol (LDLc) and an active review with a selection of those patients. Results were analyzed using SPSS V27, where descriptive statistics and relevant correlation tests were employed.

Results

Eighteen general practices agreed to take part in the study. In the initial survey, respondents rated their personal and practice familiarity with FH as slightly below average. Around one-third of respondents were not aware of FH guidelines. Of over 55,000 adult patient records searched, only 0.2% had a recorded FH diagnosis and 3.9% had ever had an LDLc above 4.9 mmol/l. Eight practices completed 198 chart reviews. Among these, 29.8% of patients had a family history recorded, and 22.2% had a family history of CVD recorded. Female patients had higher averages for highest and recent LDLc. Seventy patients underwent a clinical review-with 27% of these patients identified as "probable" or "definite FH." There was a statistically significant (p = 0.002) relationship between FH status and whether the patient had other CVD risk factors.

Conclusion

General practitioners in Ireland had similar levels of awareness of FH compared to findings from elsewhere. The activities discussed encouraged clinicians to consider FH when talking to their patients, especially those with elevated LDLc at an early age. Broader awareness of the condition could increase conversations about FH and benefit patient outcomes.

Implementation of a biochemical, clinical, and genetic screening programme for familial hypercholesterolemia in 26 centres in Spain: The ARIAN study

Background: Familial hypercholesterolemia (FH) is clearly underdiagnosed and undertreated. The aim of this present study is to assess the benefits of FH screening through a joint national program implemented between clinical laboratories and lipid units.

Methods: All clinical laboratory tests from 1 January 2017 to 31 December 2018 were reviewed, and those with LDL cholesterol (LDL-C) levels &gt;250 mg/dl were identified in subjects &gt;18 years of age of both sexes. Once secondary causes had been ruled out, the treating physician was contacted and advised to refer the patient to an LU to perform the Dutch Lipid Clinic Network score and to request genetic testing if the score was ≥6 points. Next Generation Sequencing was used to analyse the promoter and coding DNA sequences of four genes associated with FH (LDLR, APOB, PCSK9, APOE) and two genes that have a clinical overlap with FH characteristics (LDLRAP1 and LIPA). A polygenic risk score based on 12 variants was also obtained.

Results: Of the 3,827,513 patients analyzed in 26 centers, 6,765 had LDL-C levels &gt;250 mg/dl. Having ruled out secondary causes and known cases of FH, 3,015 subjects were included, although only 1,205 treating physicians could be contacted. 635 patients were referred to an LU and genetic testing was requested for 153 of them. This resulted in a finding of sixty-seven pathogenic variants for FH, 66 in the LDLR gene and one in APOB. The polygenic risk score was found higher in those who had no pathogenic variant compared to those with a pathogenic variant.

Conclusion: Despite its limitations, systematic collaboration between clinical laboratories and lipid units allows for the identification of large numbers of patients with a phenotypic or genetic diagnosis of FH, which will reduce their vascular risk. This activity should be part of the clinical routine.