GENetic characteristics and REsponse to lipid-lowering therapy in familial hypercholesterolemia: GENRE-FH study

Lipid-lowering therapies and long-term stroke prevention in East Asians: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Stroke prevention is a pressing global health priority, with reducing elevated lipids recognized as a key strategy. East Asians, constituting more than 1.6 billion individuals and the largest racial group worldwide, are a key demographic in this effort. Yet, the effectiveness of lipid-lowering therapies for stroke prevention in this population remains uncertain.

AIMS AND METHODS

We conducted a systematic review and meta-analysis of large-scale randomized controlled trials (RCTs) with at least 3 years of follow-up to evaluate the long-term impact of lipid-lowering therapies on stroke incidence in East Asians. We systematically searched four electronic databases up to 11 January 2024. The association was quantified using relative risk (RR) with a 95% confidence interval (CI), and between-study heterogeneity was evaluated using the I2 statistic. In addition, we utilized the Cochrane Risk of Bias Tool to assess the risk of bias in each included RCT and applied the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach to evaluate the certainty of the evidence.

RESULTS

This study incorporated data from nine large-scale RCTs involving 54,354 participants. Our findings of overall analyses revealed that lipid-lowering therapies did not significantly affect the long-term incidence of all strokes (9 RCTs; 54,354 participants; RR = 0.98 (95% CI = 0.87-1.10); P = 0.75), ischemic stroke (7 RCTs; 52,059 participants; RR = 0.91 (95% CI, = 0.79-1.04); P = 0.16), or hemorrhage stroke (7 RCTs; 52,059 participants; RR = 1.24 (95% CI = 0.97-1.59); P = 0.09) in East Asians. Notably, there was no evidence of heterogeneity or publication bias, and the quality of evidence assessed using GRADE methodologies was rated as high. Sensitivity analyses confirmed the robustness of our results, with no single study significantly affecting the overall findings. Furthermore, subgroup analyses consistently supported the conclusions, further bolstering the reliability of our study.

CONCLUSIONS

Lipid-lowering therapies did not demonstrate any beneficial effects on long-term stroke prevention among East Asians.

Gene Mutation in Patients with Familial Hypercholesterolemia and Response to Alirocumab Treatment-A Single-Centre Analysis

Background: Familial hypercholesterolemia (FH) is an autosomal dominant genetic disorder characterized by significantly elevated levels of low-density lipoprotein (LDL) cholesterol, which plays a major role in the progression of atherosclerosis and leads to a heightened risk of premature atherosclerotic cardiovascular disease. Methods: We have carried out an observational study on a group of 17 patients treated at the Outpatient Lipid Clinic from 2019 to 2024. Result: The most frequent mutation observed was found in the LDL receptor (LDLR) gene, which was identified in ten patients (58.8%). Five patients were identified to have a mutation in the apolipoprotein B (APOB) gene, whereas two patients had two points mutations, one in the LDLR, and the other in the APOB gene. The average age of patients with LDLR mutation was 54.8 (12.3); for APOB mutation it was 61.4 (9.3) and for patients with two points mutation it was 61.5 (14.8). The study results showed that at Week 12, individuals with LDLR-defective heterozygotes who were given alirocumab 150 mg every two weeks experienced a 63.0% reduction in LDL cholesterol levels. On the other hand, individuals with APOB heterozygotes experienced a 59% reduction in LDL cholesterol levels. However, in patients with double heterozygous for mutations in LDLR and APOB genes, there was a hyporesponsiveness to alirocumab, and the reduction in LDL-C was only by 23% in two individuals. Conclusions: In patients with a single mutation, there was a greater response to treatment with alirocumab in contrast to patients with double heterozygous mutation, who did not respond to treatment with PCSK9 inhibitors.

Novel LDLR Variant in Familial Hypercholesterolemia: NGS-Based Identification, In Silico Characterization, and Pharmacogenetic Insights

BACKGROUND

Familial Hypercholesterolemia (FH) is a hereditary condition that causes a rise in blood cholesterol throughout a person's life. FH can result in myocardial infarction and even sudden death if not treated. FH is thought to be caused mainly by variants in the gene for the low-density lipoprotein receptor (LDLR). This study aimed to investigate the genetic variants in FH patients, verify their pathogenicity, and comprehend the relationships between genotype and phenotype. Also, review studies assessed the relationship between the LDLR null variants and the reaction to lipid-lowering therapy.

METHODS

The study utilised high-throughput next-generation sequencing for genetic screening of FH-associated genes and capillary sequencing for cascade screening. Furthermore, bioinformatic analysis was employed to describe the pathogenic effects of the revealed novel variant on the structural features of the corresponding RNA molecule.

RESULTS

We studied the clinical signs of hypercholesterolemia in a Saudi family with three generations of FH. We discovered a novel frameshift variant (c.666_670dup, p.(Asp224Alafs*43) in the LDLR and a known single nucleotide variant (c.9835A > G, p.(Ser3279Gly) in the APOB gene. It is thought that the LDLR variant causes a protein to be prematurely truncated, likely through nonsense-mediated protein decay. The LDLR variant is strongly predicted to be pathogenic in accordance with ACMG guidelines and co-segregated with the FH clinical characteristics of the family. This LDLR variant exhibited severe clinical FH phenotypes and was restricted to the LDLR protein's ligand-binding domain. According to computational functional characterization, this LDLR variant was predicted to change the free energy dynamics of the RNA molecule, thereby affecting its stability. This frameshift variant is thought to eliminate important functional domains in LDLR that are required for receptor recycling and LDL particle binding. We provide insight into how FH patients with a null variant in the LDLR gene respond to lipid-lowering therapy.

CONCLUSIONS

The findings expand the range of FH variants and assist coronary artery disease preventive efforts by improving diagnosis, understanding the genotype-phenotype relationship, prognosis, and personalised therapy for patients with FH.

2022 Consensus statement on the management of familial hypercholesterolemia in Korea

Familial hypercholesterolemia (FH) is the most common monogenic disorder. Due to the marked elevation of cardiovascular risk, the early detection, diagnosis, and proper management of this disorder are critical. Herein, the 2022 Korean guidance on this disease is presented. Clinical features include severely elevated low-density lipoprotein cholesterol (LDL-C) levels, tendon xanthomas, and premature coronary artery disease. Clinical diagnostic criteria include clinical findings, family history, or pathogenic mutations in the LDLR, APOB, or PCSK9. Proper suspicion of individuals with typical characteristics is essential for screening. Cascade screening is known to be the most efficient diagnostic approach. Early initiation of lipid-lowering therapy and the control of other risk factors are important. The first-line pharmacological treatment is statins, followed by ezetimibe, and PCSK9 inhibitors as required. The ideal treatment targets are 50% reduction and < 70 or < 55 mg/dL (in the presence of vascular disease) of LDL-C, although less strict targets are frequently used. Homozygous FH is characterized by untreated LDL-C > 500 mg/dL, xanthoma since childhood, and family history. In children, the diagnosis is made with criteria, including items largely similar to those of adults. In women, lipid-lowering agents need to be discontinued before conception.

Individualized Treatment for Patients With Familial Hypercholesterolemia

Familial hypercholesterolemia (FH) is one of the most common and, therefore, important inherited disorders in preventive cardiology. This disease is mainly caused by a single pathogenic mutation in the low-density lipoprotein receptor or its associated genes. Moreover, it is correlated with a high risk of cardiovascular disease. However, the phenotype severity even in this monogenic disease significantly varies. Thus, the current study aimed to describe FH and its importance and the factors (inherited and acquired) contributing to differences in phenotype severity. Different lipid-modification therapies according to these factors can lead to individualized treatments, which are also essential in the general populations.

2022 Consensus Statement on the Management of Familial Hypercholesterolemia in Korea

Familial hypercholesterolemia (FH) is the most common monogenic disorder. Due to the marked elevation of cardiovascular risk, the early detection, diagnosis, and proper management of this disorder are critical. Herein, the 2022 Korean guidance on this disease is presented. Clinical features include severely elevated low-density lipoprotein-cholesterol (LDL-C) levels, tendon xanthomas, and premature coronary artery disease. Clinical diagnostic criteria include clinical findings, family history, or pathogenic mutations in the LDLR, APOB, or PCSK9. Proper suspicion of individuals with typical characteristics is essential for screening. Cascade screening is known to be the most efficient diagnostic approach. Early initiation of lipid-lowering therapy and the control of other risk factors are important. The first-line pharmacological treatment is statins, followed by ezetimibe, and PCSK9 inhibitors as required. The ideal treatment targets are 50% reduction and <70 mg/dL or <55 mg/dL (in the presence of vascular disease) of LDL-C, although less strict targets are frequently used. Homozygous FH is characterized by untreated LDL-C >500 mg/dL, xanthoma since childhood, and family history. In children, the diagnosis is made with criteria, including items largely similar to those of adults. In women, lipid-lowering agents need to be discontinued before conception.

Role of Genetics in Preventive Cardiology: Focused on Dyslipidemia

Although lipid-lowering therapy has become a mainstay in preventive cardiology, many people do not realize how individual's genetic information and current genetic knowledge can be used in clinical practice. Genetic testing is one of the methods to find etiology in monogenic or polygenic dyslipidemia. Pharmacogenetic data may provide guidance for selection of treatment-eligible patients and lipid-lowering therapeutics. In addition, recent progress in research regarding genetics, bioinformatics, and pharmacological platforms accelerated drug target discovery and drug development in the field of dyslipidemia and cardiovascular disease prevention.

Dyslipidemia is a strong risk factor for cardiovascular disease as well as a major target for its prevention. Along with the progress in genetic research techniques and bioinformatics analysis, genetic knowledge helps manage individuals with dyslipidemia. Familial hypercholesterolemia, the most common monogenic lipid disorder, can be diagnosed clinically without confirming pathogenic mutations. However, it can be difficult to do so due to uncertain family history, and genetic testing is of vital importance in such cases. Conversely, recent studies have revealed that combination effect of rare and common variants is frequent in people with other extreme lipid phenotypes. Genetic characteristics are helpful for prediction and selection of patients with high risk for cardiovascular disease or poor response to lipid-lowering therapy. In the past decade, studies using new genetic techniques have identified novel associations among lipid metabolism-associated genes, intermediate lipid phenotypes, and cardiovascular health. Such findings shed light on new drug targets. With improvements in the platforms and processes for drug development, several recent clinical trials showed promising results regarding lipid control and potential cardiovascular disease prevention.

Phenotypic and Genetic Analyses of Korean Patients with Familial Hypercholesterolemia: Results from the KFH Registry 2020

Aims: Familial hypercholesterolemia (FH) is currently a worldwide health issue. Understanding the characteristics of patients is important for proper diagnosis and treatment. This study aimed to analyze the phenotypic and genetic features, including threshold cholesterol levels, of Korean patients with FH.

Methods: A total of 296 patients enrolled in the Korean FH registry were included, according to the following criteria: low-density lipoprotein-cholesterol (LDL-C) ＞190 mg/dL with tendon xanthoma or family history compatible with FH, or LDL-C ＞225 mg/dL. DNA sequences of three FH-associated genes were obtained using whole-exome or target exome sequencing. Threshold cholesterol levels for differentiating patients with FH/pathogenic variant (PV) carriers and predictors of PVs were identified.

Results: Of the 296 patients, 104 had PVs and showed more obvious clinical findings, including higher cholesterol levels. PV rates ranged from 30% to 64% when patients were categorized by possible or definite type according to the Simon Broome criteria. Frequent PV types included missense variants and copy number variations (CNVs), while the most frequent location of PVs was p.P685L inLDLR. The threshold LDL-C levels for patient differentiation and PV prediction were 177 and 225 mg/dL, respectively. Younger age, tendon xanthoma, and higher LDL-C levels were identified as independent predictors of PVs, while traditional cardiovascular risk factors were predictors of coronary artery disease.

Conclusions: Korean patients with FH had variable PV rates depending on diagnostic criteria and distinctive PV locations. The reported threshold LDL-C levels pave the way for efficient patient care in this population.