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AIMS: Elevated lipoprotein (a) (Lp[a]), predominantly determined by genetic variability, causes atherosclerotic cardiovascular disease (ASCVD), particularly in patients with familial hypercholesterolemia (FH). We aimed to elucidate the clinical impact of Lp(a) and cumulative exposure to low-density lipoprotein cholesterol (LDL-C) on CAD in patients with FH. METHODS: One hundred forty-seven patients clinically diagnosed with heterozygous familial hypercholesterolemia (HeFH) were retrospectively investigated. Patients were divided into 2 groups according to the presence of CAD. Their clinical characteristics and lipid profiles were evaluated. RESULTS: There were no significant differences in untreated LDL-C levels between the 2 groups (p=0.4), whereas the cumulative exposure to LDL-C and Lp(a) concentration were significantly higher in patients with CAD (11956 vs. 8824 mg-year/dL, pï¼0.01; 40 vs. 14 mg/dL, pï¼0.001, respectively). A receiver operating characteristic (ROC) curve analysis demonstrated that the cutoff values of Lp(a) and cumulative LDL-C exposure to predict CAD in patients with FH were 28 mg/dL (AUC 0.71) and 10600 mg-year/dL (AUC 0.77), respectively. A multivariate analysis revealed that cumulative LDL-C exposure ≥ 10600 mg-year/dL (pï¼0.0001) and Lp(a) level ≥ 28 mg/dL (pï¼0.001) were independent predictors of CAD. Notably, the risk of CAD remarkably increased to 85.7% with smoking, Lp(a) ≥ 28 mg/dL, and cumulative LDL-C exposure ≥ 10600 mg-year/dL (odds ratio: 46.5, 95%CI: 5.3-411.4, pï¼0.001). CONCLUSIONS: This study demonstrated an additive effect of Lp(a) and cumulative LDL-C exposure on CAD in patients with HeFH. Interaction with traditional risk factors, particularly smoking and cumulative LDL-C exposure, enormously enhances the cardiovascular risk in this population.
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Background: Based on Finnish LDLR-founder variations, the prevalence of familial hypercholesterolemia (FH) in Finland is estimated to be at least 1:600. Patients with FH have increased risk of premature coronary artery disease (CAD) and thus the prevalence of FH is expected to be higher in this subgroup. Objective: To assess the prevalence of monogenic FH in a Finnish cohort of patients with premature CAD and elevated low-density lipoprotein cholesterol (LDL-C) levels. Methods: Among 28,295 patients undergoing angiography at Heart Hospital at Tampere University Hospital between 2007 and 2017, we identified 162 patients diagnosed with premature CAD (men aged <55â years and women aged <60â years) and history of high LDL-C (≥5â mmol/L) levels without secondary causes of hypercholesterolemia. Clinical probability of FH was estimated, and genetic testing of FH was carried out in 80 patients with informed consent. Results: Of the 80 patients with premature CAD and history of high LDL-C levels, 70% were men; the age at diagnosis of CAD for male and female patients was 48 and 53â years, respectively. In total, 58 (73%) patients had probable (n = 54) or definite (n = 4) FH based on Dutch Lipid Clinic Network criteria. A pathogenic variant of FH was found in five (6%) patients. Prevalence of the genetically verified FH was 1:16. The FH variant was found in 75% of patients with definite FH. Conclusions: The prevalence of genetically verified FH was 1:16 among patients with premature CAD and elevated LDL-C level, which is 38 times higher than the estimated prevalence of 1:600 in the general Finnish population.
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Familial Hypercholesterolemia (FH) is an inherited disorder that significantly increases an individual's risk of developing premature cardiovascular disease (CVD). Early intervention involving lifestyle modification and medication is crucial in preventing CVD. Prior studies have shown that lipid-lowering therapy in children is safe and effective. Despite FH being a treatable and manageable condition, the condition is still underdiagnosed and undertreated. Universal lipid screening (ULS) in children has been recommended by some medical experts in the United States as a strategy to identify cases of FH and maximize the benefits of early invention. However, lipid screening is not routinely offered in pediatric clinics. This study aimed to explore parental experience with FH diagnosis in their children, identify key facilitators and barriers in children's diagnosis and care, and examine parental perspectives on ULS in children in the United States. A total of fourteen semi-structured interviews were conducted with participants recruited through the Family Heart Foundation. Thematic analysis identified three key themes: role of family history in facilitating child's FH diagnosis, barriers and challenges in post-diagnosis care, and attitudes towards ULS in children. All participants supported ULS in children and emphasized the value of early diagnosis and treatment for FH. However, a lack of guidance or referral after the child's diagnosis was a concern raised by many participants. This underscores the need for accessible and comprehensive care amid ongoing efforts to increase pediatric diagnosis of FH.
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Introduction: Xanthomas are skin swellings that are caused by the accumulation of cholesterol and lipids in the body. They are associated with lipid disorders, such as familial hypercholesterolemia (FH). FH is a rare genetic disorder, which is characterized mainly by high levels of low density lipoprotein cholesterol. Case presentation: The authors report a case of an 11-year-old female who had multiple swellings all over the body with the largest measuring 7×4×3 cm in diameter. These lesions were gradually increasing in size since 4 years. She was being bullied by her school colleagues because of swellings appearance. Clinical examination revealed multiple yellowish masses on the patient's elbows, knees, and buttocks which were painless, firm, and nontender. Laboratory tests revealed elevated levels of serum cholesterol (512 mg/dl) and low density lipoprotein cholesterol (469.2 mg/dl). Masses ultrasound showed similar echogenicity to upper and lower extremities subcutaneous fat. Incisional biopsy microscopic images revealed clusters of foam cells. These findings led to a diagnosis of Homozygous FH and she underwent surgery to remove the xanthomas on her elbows. Discussion: Xanthomas are small, yellowish skin swellings that form due to the presence of high lipids. As they are typically painless and small, this could lead to a late treatment or misdiagnosis. Drugs, lifestyle changes, and surgery represent treatment plan options. Conclusion: Xanthomas can be the first indication of an underlying hypercholesterolemia problem and this case report highlights the importance of early diagnosis of Homozygous FH by providing the suitable management for this case in its early stages which can prevent developing serious complication.
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Background: Familial hypercholesterolemia (FH) is an autosomal dominant disorder characterized by increased LDL-cholesterol levels. About 85% of FH cases are caused by LDLR mutations encoding the low-density lipoprotein receptor (LDLR). LDLR is synthesized in the endoplasmic reticulum (ER) where it undergoes post-translational modifications and then transported through Golgi apparatus to the plasma membrane. Over 2900 LDLR variants have been reported in FH patients with limited information on the pathogenicity and functionality of many of them. This study aims to elucidate the cellular trafficking and functional implications of LDLR missense variants identified in suspected FH patients using biochemical and functional methods. Methods: We used HeLa, HEK293T, and LDLR-deficient-CHO-ldlA7 cells to evaluate the subcellular localization and LDL internalization of ten LDLR missense variants (p.C167F, p.D178N, p.C243Y, p.E277K, p.G314R, p.H327Y, p.D477N, p.D622G, p.R744Q, and p.R814Q) reported in multiethnic suspected FH patients. We also analyzed the functional impact of three variants (p.D445E, p.D482H, and p.C677F), two of which previously shown to be retained in the ER. Results: We show that p.D622G, p.D482H, and p.C667F are largely retained in the ER whereas p.R744Q is partially retained. The other variants were predominantly localized to the plasma membrane. LDL internalization assays in CHO-ldlA7 cells indicate that p.D482H, p.C243Y, p.D622G, and p.C667F have quantitatively lost their ability to internalize Dil-LDL with the others (p.C167F, p.D178N, p.G314R, p.H327Y, p.D445E, p.D477N, p.R744Q and p.R814Q) showing significant losses except for p.E277K which retained full activity. However, the LDL internalization assay is only to able evaluate the impact of the variants on LDL internalization and not the exact functional defects such as failure to bind LDL. The data represented illustrate the hypomorphism nature of variants causing FH which may explain some of the variable expressivity of FH. Conclusion: Our combinatorial approach of in silico, cellular, and functional analysis is a powerful strategy to determine pathogenicity and FH disease mechanisms which may provide opportunitites for novel therapeutic strategies.
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There is a gap of knowledge about the clinical and pathophysiological implications resulting from the interaction between primary hyperlipidemias and type 2 diabetes (T2D). Most of the existing evidence comes from sub-analyses of cohorts; scant information derives from randomized clinical trials. The expected clinical implications of T2D in patients with primary hyperlipidemias is an escalation of their already high cardiovascular risk. There is a need to accurately identify patients with this dual burden and to adequately prescribe lipid-lowering therapies, with the current advancements in newer therapeutic options. This review provides an update on the interactions of primary hyperlipidemias, such as familial combined hyperlipidemia, familial hypercholesterolemia, multifactorial chylomicronemia, lipoprotein (a), and type 2 diabetes.
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Familial Hypercholesterolemia (FH) is one of the best-characterized inborn errors of metabolism, with an estimated prevalence of 1:250 in the general population. Only approximately 10% of the affected subjects are diagnosed and, therefore, under medical care, including drug therapy or, in severe cases, apheresis. Screening at the age of 6-10 years would be useful and cost-effective. There is enough evidence that children and adolescents with FH should be treated in order to reduce elevated Total cholesterol and LDL-c levels and, therefore, avoid the risk of early cardiovascular diseases. As FH was described more than 130 years ago, it is surprising that the knowledge of that very important metabolic disorder is insufficient. The present report describes clinical and pathophysiological characteristics and nutritional and medical therapies in children with familial hypercholesterolemia.
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The COVID-19 pandemic lockdowns affected the lifestyles of children and adolescents, leading to an increase in childhood obesity. Paediatric patients with familial hypercholesterolemia (FH) may be more susceptible to lockdown effects due to their increased cardiovascular risk. However, data are lacking. We investigated the effect of lockdowns on the metabolic profile of paediatric patients with FH. Blood lipids and anthropometry measured in September 2021-April 2022 were retrospectively compared with pre-pandemic values. Thirty participants were included (1-16 years; 57% female). From baseline to post-pandemic, median [P25, P75] blood LDL-C concentration was 125 [112, 150] mg/dL vs. 125 [100, 147] mg/dL (p = 0.894); HDL-C was 58 [52, 65] mg/dL vs. 56 [51, 61] mg/dL (p = 0.107); triglycerides were 64 [44, 86] mg/dL vs. 59 [42, 86] mg/dL (p = 0.178). The BMI z-score did not change significantly (0.19 [-0.58, 0.89] vs. 0.30 [-0.48, 1.10], p = 0.524). The lack of deterioration in metabolic profiles during lockdowns is positive, as some deterioration was expected. We speculate that patients and caregivers were successfully educated about healthy lifestyle and dietary habits. Our results should be interpreted with caution since the study sample was small and heterogeneous. Multicentre research is needed to better understand the impact of lockdowns on this population.
Subject(s)
COVID-19 , Hyperlipoproteinemia Type II , SARS-CoV-2 , Humans , COVID-19/prevention & control , COVID-19/epidemiology , Female , Male , Child , Hyperlipoproteinemia Type II/blood , Adolescent , Retrospective Studies , Child, Preschool , Anthropometry , Infant , Cholesterol, LDL/blood , Triglycerides/blood , Pediatric Obesity/epidemiology , Body Mass Index , Pandemics , Cholesterol, HDL/blood , Quarantine , Lipids/bloodABSTRACT
According to the latest guidelines of European and American medical societies, genetic testing (GT) is essential in cardiovascular diseases for establishing diagnosis, predicting prognosis, enabling initiation of disease-modifying therapy, and preventing sudden cardiac death. The GT result may be relevant for cascade GT in the patient's relatives, for planning his/her profession and physical activity, and for procreative counseling. This position statement has been prepared due to the scarcity of GT in cardiovascular diseases in Poland and the need to expand its availability. We give a concise description of the genetic background of cardiomyopathies, channelopathies, aortopathies, familial hypercholesterolemia, pheochromocytomas, and paragangliomas. The article discusses various aspects of GT in specific populations, such as children or athletes, and also presents prenatal genetic diagnostics. We propose recommendations for GT and counselling, which take into account Polish needs and capabilities. We give an outline of legal regulations, good clinical practice in GT with respect for patient rights, the role of cardiologists and clinical geneticists in GT planning and post-test counseling, and the requirements for laboratories performing genetic tests. The Polish Cardiac Society and Polish Society of Human Genetics experts speak with one voice with cardiovascular patient communities to underline the need for a law on GT and increasing the availability of GT for cardiovascular patients.
Subject(s)
Cardiovascular Diseases , Genetic Testing , Societies, Medical , Humans , Poland , Cardiovascular Diseases/genetics , Cardiovascular Diseases/diagnosis , Cardiology/standards , Genetic Counseling , FemaleABSTRACT
BACKGROUND AND AIMS: Familial hypercholesterolemia (FH) is a genetic disorder marked by high LDL cholesterol and an increased premature coronary artery disease (CAD) risk. Current dichotomous classification of LDL receptor gene (LDLR) variants may inadequately capture patient variability in LDL cholesterol levels and CAD risk. This study assessed a novel approach for determining LDLR variant severity using variant-specific LDL cholesterol percentiles. METHODS: Participants of the Dutch FH cascade screening program were screened for 456 LDLR variants. For each LDLR variant carrier, a sex- and age-specific LDL cholesterol percentile was derived from the LDL cholesterol level measured at study entry, i.e. generally from the blood drawn for DNA analysis. These percentiles were used to calculate the mean LDL cholesterol percentile for each variant. Based on the variant-specific LDL cholesterol percentiles, carriers were grouped into the following LDL cholesterol strata: <75th, 75th-88th, 88th-92nd, 92nd-96.5th, 96.5th-98th, and ≥98th percentile. Additionally, variants were categorized into class 1 (LDLR deficient) and non-class 1 (often LDLR defective) variants. CAD risk between carriers in the different LDL cholesterol strata and non-carriers was compared using a Cox proportional hazard model. RESULTS: Out of 35,067 participants, 12,485 (36 %) LDLR variant carriers (mean age 38.0 ± 20.0 years, 47.7 % male) were identified. Carriers had a 5-fold higher CAD risk compared with non-carriers. Hazard ratios for CAD increased gradually from 2.2 (95%CI 0.97-5.0) to 12.0 (95%CI 5.5-24.8) across the LDL cholesterol strata. A 7.3-fold and 3.9-fold increased CAD risk was observed in carriers of class 1 and non-class 1 LDLR variants, respectively. CONCLUSIONS: This study presents a refined approach for classifying LDLR variants based on their impact on LDL cholesterol levels, allowing for more precise, genotype-specific CAD risk estimation in FH patients compared with traditional methods.
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The patient was a 54-year-old woman with familial hypercholesterolemia and remarkable Achilles tendon thickening. At 20 years old, the patient had a total cholesterol level of approximately 300 mg/dL. She started receiving rosuvastatin (5 mg/day) for low-density lipoprotein cholesterol (LDL-C) 235 mg/dL at 42 years old, which was increased to 10 mg/day at 54 years old, decreasing her serum LDL-C level to approximately 90 mg/dL. The serum Lp (a) level was 9 mg/dL. A computed tomography coronary angiogram showed no significant stenosis. Next-generation sequencing revealed a frameshift variant in LDL receptor (LDLR) (heterozygous) and a missense variant in proprotein convertase subtilisin/kaxin type 9 (PCSK9) (heterozygous). Continued statin therapy, in addition to low Lp (a) and female sex, can help prevent cardiovascular disease.
Subject(s)
Achilles Tendon , Hyperlipoproteinemia Type II , Proprotein Convertase 9 , Receptors, LDL , Humans , Achilles Tendon/diagnostic imaging , Achilles Tendon/pathology , Female , Hyperlipoproteinemia Type II/genetics , Hyperlipoproteinemia Type II/drug therapy , Hyperlipoproteinemia Type II/blood , Hyperlipoproteinemia Type II/complications , Hyperlipoproteinemia Type II/diagnosis , Receptors, LDL/genetics , Middle Aged , Proprotein Convertase 9/genetics , Rosuvastatin Calcium/therapeutic use , Atherosclerosis/genetics , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Cholesterol, LDL/blood , Mutation, Missense , Japan , East Asian PeopleABSTRACT
Familial hypercholesterolemia (FH) poses a global health challenge due to high incidence rates and underdiagnosis, leading to increased risks of early-onset atherosclerosis and cardiovascular diseases. Early detection and treatment of FH is critical in reducing the risk of cardiovascular events and improving the long-term outcomes and quality of life for affected individuals and their families. Traditional therapeutic approaches revolve around lipid-lowering interventions, yet challenges persist, particularly in accurate and timely diagnosis. The current diagnostic landscape heavily relies on genetic testing of specific LDL-C metabolism genes, often limited to specialized centers. This constraint has led to the adoption of alternative clinical scores for FH diagnosis. However, the rapid advancements in artificial intelligence (AI) and machine learning (ML) present promising solutions to these diagnostic challenges. This review explores the intricacies of FH, highlighting the challenges that are encountered in the diagnosis and management of the disorder. The revolutionary potential of ML, particularly in large-scale population screening, is highlighted. Applications of ML in FH screening, diagnosis, and risk stratification are discussed, showcasing its ability to outperform traditional criteria. However, challenges and ethical considerations, including algorithmic stability, data quality, privacy, and consent issues, are crucial areas that require attention. The review concludes by emphasizing the significant promise of AI and ML in FH management while underscoring the need for ethical and practical vigilance to ensure responsible and effective integration into healthcare practices.
Subject(s)
Artificial Intelligence , Hyperlipoproteinemia Type II , Humans , Hyperlipoproteinemia Type II/diagnosis , Hyperlipoproteinemia Type II/therapy , Hyperlipoproteinemia Type II/genetics , Risk Assessment/methods , Early Diagnosis , Mass Screening/methods , Early Medical Intervention/methodsABSTRACT
AIMS: Little data exists for evaluating the prevalence and patient characteristics of familial hypercholesterolemia (FH) according to the latest 2022 guidelines for FH published by the Japan Atherosclerosis Society (JAS), which revised the Achilles tendon thickness (ATT) threshold from 9.0 mm in both sexes to 8.0 mm in men and 7.5 mm in women. This study used a nationwide registry of patients with acute coronary syndrome (ACS) to evaluate the prevalence of FH according to the latest diagnostic criteria for FH and to investigate the application of Achilles tendon imaging in the diagnosis of FH.A previous prospective observational study at 59 Japanese centers involving consecutive patients with ACS who were managed between April 2015 and August 8, 2016 was conducted to explore lipid management and persistent risk in patients hospitalized for ACS (EXPLORE-J). The study population consisted of 1,944 EXPLORE-J enrollees. RESULTS: According to the diagnostic criteria for FH in the 2022 JAS guidelines, the prevalence of probable or definite was among patients with ACS was 6.6% (127/1944). Among patients with premature ACS (male, age ï¼55 years; female, age ï¼65 years), the prevalence of FH was 10.1% (43/427). The mean ages were of the probable FH and definite FH groups were 59.9 and 61.0 years, respectively, while the mean age of the possible-or-unlikely FH group was 66.4 years (significantly older). Relative to the possible-or-unlikely FH group, the low-density lipoprotein cholesterol (LDL-C) levels were similar in the probable FH group and and significantly higher in the definite FH group. CONCLUSIONS: The prevalence of FH was considerably higher than previously reported, especially for patients with premature ACS. The age and LDL-C levels of the patients in the probable FH and definite FH groups were similar.
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BACKGROUND: In Slovakia, a mandatory national universal pediatric total cholesterol (TC) screening program is in place to identify cases of familial hypercholesterolemia (FH). However, the program's effectiveness has not been systematically assessed. OBJECTIVE: This study aimed to estimate the prevalence of FH among parents of children that had elevated TC levels identified during screening. METHODS: This prospective, non-interventional, observational study enrolled parents of 11-year-old children who underwent TC screening in 23 selected pediatric outpatient clinics between 2017 and 2018. FH was diagnosed using the Dutch Lipid Clinic Network (DLCN) criteria and targeted next-generation sequencing. The primary objective was to estimate the proportion of children with a TC level of >188 mg/dL (>4.85 mmol/L) who had a parent with a confirmed diagnosis of FH. RESULTS: A total of 112 parents of 56 children with an elevated TC level were enrolled. Five children (8.9%) had a parent in whom FH was genetically confirmed. Without genetic analysis, all five parents would only be diagnosed with "possible FH" by DLCN criteria. Of parents, 83.9% (n = 94/112) had an LDL-C level of >116 mg/dL (>3 mmol/L), but only 5.3% (n = 5/94) received lipid-lowering therapy. Among the five parents with genetically confirmed FH, all had an LDL-C level >116 mg/dL (>3 mmol/L), with a mean (±SD) of 191 (±24) mg/dL (4.94 [±0.61] mmol/L). Only two of these parents received lipid-lowering therapy. CONCLUSIONS: The present study demonstrates the significance of mandatory universal pediatric TC screening in identifying families with FH and other at-risk families in need of lipid-lowering therapy.
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BACKGROUND: The atherogenic characteristics of heterozygous familial hypercholesterolemia (HeFH) increase the risk of premature atherosclerotic cardiovascular disease including not only coronary artery disease but ischemic stroke. Asymptomatic intracranial artery stenosis/occlusion (IASO) is a major cause of ischemic stroke, but it has not yet been fully characterized in patients with HeFH. METHODS AND RESULTS: This study analyzed 147 clinically diagnosed subjects with HeFH who underwent magnetic resonance imaging/magnetic resonance angiography imaging for evaluation of IASO (≥50% diameter stenosis). Major adverse cerebrovascular and cardiovascular events (cardiac death, ischemic stroke, and acute coronary syndrome) were compared in patients with HeFH with and without asymptomatic IASO. Asymptomatic IASO was observed in 13.6% of patients with HeFH. The untreated low-density lipoprotein cholesterol level (240±95 versus 244±75 mg/dL; P=0.67) did not differ between the 2 groups. Despite the use of lipid-lowering therapies (statin, P=0.71; high-intensity statin, P=0.81; ezetimibe, P=0.33; proprotein convertase subxilisin/kexin type 9 inhibitor, P=0.39; low-density lipoprotein apheresis, P=0.14), on-treatment low-density lipoprotein cholesterol level in patients with both HeFH and IASO was still suboptimally controlled (97±62 versus 105±50 mg/dL; P=0.17), accompanied by a higher triglyceride level (median, 109 versus 79 mg/dL; P=0.001). During the 12.4-year observational period (interquartile range, 6.2-24.6 years), asymptomatic IASO exhibited a 4.04-fold greater likelihood of experiencing a major adverse cardiovascular event (95% CI, 1.71-9.55; P=0.001) in patients with HeFH. This increased risk of a major adverse cardiovascular event was consistently observed in a multivariate Cox proportional hazards model adjusting clinical characteristics (hazard ratio, 4.32 [95% CI, 1.71-10.9]; P=0.002). CONCLUSIONS: A total of 13.6% of Japanese subjects with HeFH presented with asymptomatic IASO. Despite lipid-lowering therapies, patients with both HeFH and IASO more likely had elevated risk of cerebrovascular and cardiovascular events. Our findings highlight asymptomatic IASO as a phenotypic feature of HeFH-related atherosclerosis, which ultimately affects future outcomes.
Subject(s)
Asymptomatic Diseases , Hyperlipoproteinemia Type II , Magnetic Resonance Angiography , Humans , Hyperlipoproteinemia Type II/complications , Hyperlipoproteinemia Type II/genetics , Hyperlipoproteinemia Type II/blood , Hyperlipoproteinemia Type II/epidemiology , Hyperlipoproteinemia Type II/drug therapy , Male , Female , Middle Aged , Heterozygote , Adult , Risk Factors , Retrospective Studies , Constriction, Pathologic , Ischemic Stroke/epidemiology , Ischemic Stroke/etiology , Aged , Cholesterol, LDL/blood , Japan/epidemiologyABSTRACT
Background: The techniques for detecting single nucleotide polymorphisms (SNP) require lengthy and complex experimental procedures and expensive instruments that may only be available in some laboratories. Thus, a deoxyribonucleic acid (DNA)-based lateral flow assay (LFA) was developed as a point-of-care test (POCT) diagnostic tool for genotyping. In this study, single nucleotide variation (E101K) in the low-density lipoprotein receptor (LDLR) gene leading to familial hypercholesterolemia (FH) was chosen as a model. Methods: Hypercholesterolemic individuals (n = 103) were selected from the Malaysian Cohort project (UKM Medical Molecular Biology Institute) while the control samples were selected from the Biobank (UKM Medical Molecular Biology Institute). The DNA samples were isolated from whole blood. Polymerase chain reaction (PCR) amplification process was performed using bifunctional labelled primers specifically designed to correspond to the variant that differentiates wild-type and mutant DNA for visual detection on LFA. The variant was confirmed using Sanger sequencing, and the sensitivity and specificity of the LFA detection method were validated using the Agena MassARRAY® technique. Results: Out of 103 hypercholesterolemic individuals, 5 individuals (4.8%) tested positive for E101K, LDLR mutation and the rest, including healthy control individuals, tested negative. This result was concordant with Sanger sequencing and Agena MassARRAY®. These five individuals could be classified as Definite FH, as the DNA diagnosis was confirmed. The sensitivity and specificity of the variant detection by LFA is 100% compared to results using the genotyping method using Agena MassARRAY®. Conclusion: The developed LFA can potentially be used in the POC setting for detecting the E101K variant in the LDLR gene. This LFA can also be used to screen family members with E101K variant in the LDLR gene and is applicable for other SNP's detection.
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Background and aim: Many children with an FH mutation also exhibit elevated lipoprotein(a) levels, which is an independent risk factor for atherosclerotic cardiovascular disease. Studies have reported higher levels of lipoprotein(a) in adult and middle-aged women than men. There is limited knowledge on the concentration and change of lipoprotein(a) levels in children with genetic FH, and therefore we investigated sex-differences in lipoprotein(a) level and change in lipoprotein(a) in girls and boys with genetically confirmed FH. Methods: Medical records were reviewed retrospectively in 438 subjects with heterozygous FH that started follow-up below the age of 19 years at the Lipid Clinic, Oslo University Hospital in Norway, and of these we included 386 subjects with at least one Lp(a) measurement. Results: Mean (SD) age at baseline was 13.8 (7.3) years and the age was similar between sexes. Girls had a higher lipoprotein(a) level than boys at baseline: median (25-75 percentile) 223 (108-487) vs. 154 (78-360) mg/L, respectively (p < 0.01). From baseline to follow-up measurement (mean [SD] 8.9 [6.1] years apart), the mean (95 % CI) absolute and percentage change in Lp(a) level in girls was 151.4 (54.9-247.8) mg/L and 44.8 (16.4-73.1) %, respectively, and in boys it was 66.8 (22.9-110.8) mg/L and 50.5 (8.8-92.3) %, respectively (both p > 0.05). Conclusions: We found an increase in Lp(a) levels in children with genetic FH with age, and higher levels in girls than boys, which could impact risk assessment and future ASCVD. Further research is needed to elucidate whether subjects with FH could benefit from lipoprotein(a)-lowering therapies that are under current investigations.
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Familial hypercholesterolemia (FH) is a genetic disorder affecting the metabolism of lipoprotein, characterized by elevated levels of plasma concentrations of low-density lipoprotein cholesterol (LDLC). The most common FH cause is mutations within the gene that encodes for the LDL receptor (LDLR) protein. Two induced pluripotent stem cell (iPSC) lines were generated from patients with FH, each carrying a single heterozygous mutation in the LDLR gene, one is a missense mutation, c.631C > T, and the other is a splice-site mutation, c.313 + 1G > A. Both iPSC lines exhibited strong expression of pluripotency markers, demonstrated the ability to differentiate into derivatives of the three germ layers, and maintained normal karyotypes. These derived iPSC lines represent powerful tools for in vitro modeling FH and offer a promising platform for therapeutic development.
Subject(s)
Heterozygote , Hyperlipoproteinemia Type II , Induced Pluripotent Stem Cells , Mutation , Receptors, LDL , Induced Pluripotent Stem Cells/metabolism , Receptors, LDL/genetics , Receptors, LDL/metabolism , Humans , Hyperlipoproteinemia Type II/genetics , Hyperlipoproteinemia Type II/metabolism , Cell Line , Male , Female , Cell DifferentiationABSTRACT
AIMS: Familial Hypercholesterolemia (FH) is a genetic disorder of lipoprotein metabolism that causes an increased risk of premature atherosclerotic cardiovascular disease (ASCVD). Although early diagnosis and treatment of FH can significantly improve the cardiovascular prognosis, this disorder is underdiagnosed and undertreated. For these reasons the Italian Society for the Study of Atherosclerosis (SISA) assembled a Consensus Panel with the task to provide guidelines for FH diagnosis and treatment. DATA SYNTHESIS: Our guidelines include: i) an overview of the genetic complexity of FH and the role of candidate genes involved in LDL metabolism; ii) the prevalence of FH in the population; iii) the clinical criteria adopted for the diagnosis of FH; iv) the screening for ASCVD and the role of cardiovascular imaging techniques; v) the role of molecular diagnosis in establishing the genetic bases of the disorder; vi) the current therapeutic options in both heterozygous and homozygous FH. Treatment strategies and targets are currently based on low-density lipoprotein cholesterol (LDL-C) levels, as the prognosis of FH largely depends on the magnitude of LDL-C reduction achieved by lipid-lowering therapies. Statins with or without ezetimibe are the mainstay of treatment. Addition of novel medications like PCSK9 inhibitors, ANGPTL3 inhibitors or lomitapide in homozygous FH results in a further reduction of LDL-C levels. LDL apheresis is indicated in FH patients with inadequate response to cholesterol-lowering therapies. CONCLUSION: FH is a common, treatable genetic disorder and, although our understanding of this disease has improved, many challenges still remain with regard to its identification and management.
Subject(s)
Anticholesteremic Agents , Biomarkers , Cholesterol, LDL , Consensus , Genetic Predisposition to Disease , Hyperlipoproteinemia Type II , Phenotype , Humans , Anticholesteremic Agents/therapeutic use , Atherosclerosis/diagnosis , Atherosclerosis/therapy , Atherosclerosis/epidemiology , Atherosclerosis/genetics , Biomarkers/blood , Cholesterol, LDL/blood , Genetic Testing , Hydroxymethylglutaryl-CoA Reductase Inhibitors/therapeutic use , Hyperlipoproteinemia Type II/diagnosis , Hyperlipoproteinemia Type II/epidemiology , Hyperlipoproteinemia Type II/genetics , Hyperlipoproteinemia Type II/therapy , Italy/epidemiology , Mutation , Predictive Value of Tests , Prevalence , Risk Factors , Treatment OutcomeABSTRACT
PURPOSE OF REVIEW: Familial Hypercholesterolemia (FH) is a common genetic disorder characterized by lifelong elevation of severely elevated plasma low-density lipoprotein cholesterol. Atherosclerotic cardiovascular disease (ASCVD) risk accelerates after age 20. Early diagnosis allows for treatment of children with FH and creates an opportunity to identify affected relatives through reverse cascade screening (RCS). Historically, cascade screening has had little impact on identifying individuals with FH. RECENT FINDINGS: Universal cholesterol screening (UCS) to identify youth with FH, beginning at 9-11 years-of-age, is currently recommended in the U.S. The European Atherosclerosis Society has called for UCS worldwide, emphasizing the need for educational programs to increase awareness amongst healthcare professions. Underdiagnoses and undertreatment of FH remain high. Improved rates of UCS and a systematic approach to RCS are needed. The absence of a coordinated RCS program limits the benefits of UCS. Further research is needed to identify barriers to cholesterol screening in youth.