Hans J. Avis

A Systematic Review and Meta-Analysis of Statin Therapy in Children With Familial Hypercholesterolemia

Objective—Functional and morphological changes of the arterial wall already present in young children with heterozygous familial hypercholesterolemia (HeFH) suggest that treatment should be initiated early in life to prevent premature atherosclerotic cardiovascular disease. The purpose of this study was to assess the efficacy and particularly safety of statin therapy in children with HeFH. Methods and Results—We performed a meta-analysis of randomized, double-blind, placebo-controlled trials evaluating statin therapy in children aged 8 to 18 years with HeFH. Six studies (n=798 children) with 12 to 104 weeks of treatment were included. Total cholesterol, LDL cholesterol, and apolipoprotein B were significantly reduced, whereas HDL cholesterol and apolipoprotein A1 were significantly increased by statin therapy. No statistically significant differences were found between statin- and placebo-treated children with respect to the occurrence of adverse events (RR 0.99; 95% CI: 0.79 to 1.25), sexual development (RR of advancing ≥1 stage in Tanner classification 0.96; 95% CI: 0.79 to 1.17), muscle toxicity (RR of CK ≥10 times the upper limit of normal [ULN] 1.38; 95% CI: 0.18 to 10.82), or liver toxicity (RR of ≥3 times the ULN for ASAT 0.98; 95% CI: 0.23 to 4.26 and for ALAT 2.03; 95% CI: 0.24 to 16.95). We found a minimal difference in growth in favor of the statin group (0.33 cm; 95% CI: 0.03 cm to 0.63 cm). Conclusion—In addition to the fact that statin treatment is efficacious, our results support the notion that statin treatment in children with HeFH is safe. Thus, even though further studies are required to assess lifelong safety, statin treatment should be considered for all children aged 8 to 18 with HeFH.

Ten-Year Follow-up After Initiation of Statin Therapy in Children With Familial Hypercholesterolemia

Ten-Year Follow-up After Initiation of Statin Therapy in Children With Familial Hypercholesterolemia Familial hypercholesterolemia (FH) is a prevalent (1:500 individuals) inherited disorder that strongly predisposes to premature atherosclerosis and subsequent cardiovascular disease.1 In children with FH, atherosclerosis progression is observed before puberty.2 Consequently, guidelines for FH treatment advocate initiation of statins in children as young as 8 years.3 However, longterm efficacy and safety data for statin therapy initiated during childhood do not exist. We followed up a cohort of children with FH receiving statin therapy until adulthood. Methods | We conducted a cohort study of 214 children heterozygous for FH, living in the Netherlands, aged 8 to 18 years, who were randomized between 1997 and 1999 into a singlecenter, 2-year, double-blind, placebo-controlled trial of pravastatin.4 Results showed a significant regression of carotid intima-media thickness (IMT) after statin treatment compared with placebo. After the trial, all children received pravastatin (20-40 mg/d) and were followed up until March 2011 along with 95 unaffected siblings. Patients were instructed to adhere to the Step 2 diet. During follow-up, several patients switched to other statins. After 10 years, all participants underwent a physical examination, fasted blood sample, assessment of family and medical history, including the occurrence of adverse events,

Efficacy and safety of coadministration of ezetimibe and simvastatin in adolescents with heterozygous familial hypercholesterolemia.

OBJECTIVES The study evaluated the efficacy and safety of long-term coadministration of ezetimibe and simvastatin in adolescents with heterozygous familial hypercholesterolemia (HeFH). BACKGROUND Aggressive intervention to achieve lipid goals for adolescents with HeFH is recommended to reduce risk of premature cardiovascular disease. METHODS In a multicenter, randomized, double-blind, placebo-controlled study, 248 male and female subjects ages >or=10 and <or=17 years with HeFH were randomized to receive: step 1: simvastatin 10, 20, or 40 mg/day plus ezetimibe 10 mg/day or placebo for 6 weeks, followed by step 2: simvastatin 40 mg/day plus ezetimibe 10 mg/day or placebo for 27 weeks; followed by step 3: all subjects received open-label simvastatin 10 or 20 mg/day (titrated to maximum 40 mg/day) plus ezetimibe 10 mg/day for 20 weeks. Safety was assessed throughout the study. RESULTS Coadministered ezetimibe and simvastatin for 6 weeks (step 1) resulted in significantly greater mean reduction in low-density lipoprotein cholesterol (LDL-C) from baseline (49.5%) compared with simvastatin monotherapy (34.4%; p < 0.01) in pooled dose groups and in individual dose groups (46.7% vs. 30.4%, 49.5% vs. 34.3%, 52.1% vs. 38.6%, respectively; p < 0.01). At 33 weeks (step 2), ezetimibe-simvastatin subjects had a mean 54.0% reduction in LDL-C compared with a mean 38.1% reduction in simvastatin monotherapy subjects (p < 0.01). At 53 weeks (step 3), the pooled reduction in LDL-C was 49.1%. All treatment regimens were well tolerated throughout 53 weeks. CONCLUSIONS Coadministration of ezetimibe with simvastatin was safe, well tolerated, and provided higher LDL-C reduction compared with simvastatin alone in adolescents with HeFH studied up to 53 weeks. (Effects of Ezetimibe With Simvastatin in the Therapy of Adolescents With Heterozygous Familial Hypercholesterolemia; NCT00129402).

Molecular Basis of Autosomal Dominant Hypercholesterolemia Assessment in a Large Cohort of Hypercholesterolemic Children

Background— Autosomal dominant hypercholesterolemia (ADH) is characterized by elevated low-density lipoprotein cholesterol levels and premature cardiovascular disease. Mutations in the genes encoding for low-density lipoprotein receptor ( LDLR ), apolipoprotein B ( APOB ), and proprotein convertase subtilisin/kexin 9 ( PCSK9 ) underlie ADH. Nevertheless, a proportion of individuals who exhibit the ADH phenotype do not carry mutations in any of these 3 genes. Estimates of the percentage of such cases among the ADH phenotype vary widely. We therefore investigated a large pediatric population with an unequivocal ADH phenotype to assess the molecular basis of hereditary hypercholesterolemia and to define the percentage of individuals with unexplained dyslipidemia. Methods and Results— We enrolled individuals with low-density lipoprotein cholesterol levels above the 95th percentile for age and gender and an autosomal dominant inheritance pattern of hypercholesterolemia from a large referred pediatric cohort of 1430 children. We excluded children with thyroid dysfunction, nephrotic syndrome, autoimmune disease, liver disease, primary biliary cirrhosis, and obesity (body mass index >75th percentile for age and gender), as well as children referred via a cascade screening program and those from families with a known molecular diagnosis. Of the 269 children who remained after the exclusion criteria were applied, 255 (95%) carried a functional mutation ( LDLR , 95%; APOB , 5%). Conclusion— In the vast majority of children with an ADH phenotype, a causative mutation can be identified, strongly suggesting that most of the large-effect genes underlying ADH are known to date. # Clinical Perspective {#article-title-30}Background— Autosomal dominant hypercholesterolemia (ADH) is characterized by elevated low-density lipoprotein cholesterol levels and premature cardiovascular disease. Mutations in the genes encoding for low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), and proprotein convertase subtilisin/kexin 9 (PCSK9) underlie ADH. Nevertheless, a proportion of individuals who exhibit the ADH phenotype do not carry mutations in any of these 3 genes. Estimates of the percentage of such cases among the ADH phenotype vary widely. We therefore investigated a large pediatric population with an unequivocal ADH phenotype to assess the molecular basis of hereditary hypercholesterolemia and to define the percentage of individuals with unexplained dyslipidemia. Methods and Results— We enrolled individuals with low-density lipoprotein cholesterol levels above the 95th percentile for age and gender and an autosomal dominant inheritance pattern of hypercholesterolemia from a large referred pediatric cohort of 1430 children. We excluded children with thyroid dysfunction, nephrotic syndrome, autoimmune disease, liver disease, primary biliary cirrhosis, and obesity (body mass index >75th percentile for age and gender), as well as children referred via a cascade screening program and those from families with a known molecular diagnosis. Of the 269 children who remained after the exclusion criteria were applied, 255 (95%) carried a functional mutation (LDLR, 95%; APOB, 5%). Conclusion— In the vast majority of children with an ADH phenotype, a causative mutation can be identified, strongly suggesting that most of the large-effect genes underlying ADH are known to date.

Pregnancy in women suffering from familial hypercholesterolemia: a harmful period for both mother and newborn?

Purpose of review The present review aims to highlight the consequences for mother and child of profound hypercholesterolemia during pregnancy of women with familial hypercholesterolemia. Recent findings Familial hypercholesterolemia is increasingly diagnosed in younger patients due to the existence of screening programs and more widespread cholesterol testing. Increasing numbers of young female patients with familial hypercholesterolemia raise the issue of pregnancy and its consequences for the familial hypercholesterolemia patient herself but also for her offspring. When pregnancy is considered, lipid-lowering drugs are often discontinued because of the fear for teratogenic effects. The evidence for teratogenesis associated with statin use is scant and conflicting. On the other hand, several studies do suggest that pronounced hypercholesterolemia during pregnancy has adverse effects on both fetus and mother. In fact, human and animal studies reveal an enhanced tendency toward atherosclerosis in the offspring of women who suffer from hypercholesterolemia during pregnancy. In animal studies, some evidence exists that this can be reversed by treatment with lipid-lowering and antioxidative agents. Until today, however, no human studies exist that have evaluated efficacy or safety of lipid-lowering interventions in pregnant women with familial hypercholesterolemia. Summary Altogether, the suggested relationship between severe hypercholesterolemia and enhanced atherosclerosis in offspring and possibly the mother warrants further confirmation and, consequently, studies that focus on therapeutic strategies that can safely lower cholesterol levels during pregnancy in these women.

Follow-Up of Children Diagnosed with Familial Hypercholesterolemia in a National Genetic Screening Program

OBJECTIVE To assess the follow-up of children diagnosed as having familial hypercholesterolemia (FH) in the nationwide DNA-based cascade screening program (the Netherlands). STUDY DESIGN Questionnaires covering topics such as demographics, family history, physician consultation, and treatment were sent to parents of patients with FH (age 0-18 years), 18 months after diagnosis. RESULTS We retrieved 207 questionnaires of patients aged 10.9 ± 4.2 years (mean ± SD) at diagnosis; 48% were boys, and the mean low-density lipoprotein cholesterol (LDL-C) level at diagnosis was 167 ± 51 mg/dL. Of these patients, 164 (79%) consulted a physician: a general practitioner (35%), lipid-clinic specialist (27%), pediatrician (21%), internist (11%), or another physician (6%). LDL-C level at diagnosis and a positive family history for cardiovascular disease were independent predictors for physician consultation. Of the patients who visited a physician, 62% reported to have received lifestyle advice, and 43 (26%) were prescribed statin treatment. Independent predictors for medication use were age, LDL-C level, and educational level of parents. CONCLUSION The follow-up of children with FH after diagnosis established through cascade screening is inadequate. Better education of patients, parents, and physicians, with a structured follow-up after screening, should improve control of LDL-C levels and hence cardiovascular risk in children with FH.

Inheritance pattern of familial hypercholesterolemia and markers of cardiovascular risk

Studies in children and adults have resulted in conflicting evidence in the quest for the answer to the hypothesis that offspring from hypercholesterolemic mothers might have an increased cardiovascular risk. Previous studies might have suffered from limitations such as cohort size and clinical sampling bias. We therefore explored this hypothesis in large cohorts of both subjects with familial hypercholesterolemia (FH) and unaffected siblings in a wide age range. In three cohorts (cohort 1: n = 1,988, aged 0–18 years; cohort 2: n = 300, 8–30 years; cohort 3: n = 369, 18–60 years), we measured lipid and lipoproteins as well as carotid intima-media thickness (c-IMT) in offspring from FH mothers versus FH fathers. For LDL cholesterol, triglycerides (TGs), and c-IMT, we performed a pooled analysis. No significant differences could be observed in c-IMT, lipid, or lipoprotein levels from offspring of FH mothers versus FH fathers. Pooled analyses showed no significant differences for either LDL cholesterol [mean difference 0.02 (−0.06,0.11) mmol/l, P = 0.60], TGs [mean difference 0.07 (0.00,0.14) mmol/l, P = 0.08], or c-IMT [mean difference −0.00 (−0.01,0.01) mm, P = 0.86]. Our data do not support the hypothesis that cardiovascular risk markers are different between offspring from FH mothers and FH fathers.

Molecular Basis of Autosomal Dominant Hypercholesterolemia

Background— Autosomal dominant hypercholesterolemia (ADH) is characterized by elevated low-density lipoprotein cholesterol levels and premature cardiovascular disease. Mutations in the genes encoding for low-density lipoprotein receptor ( LDLR ), apolipoprotein B ( APOB ), and proprotein convertase subtilisin/kexin 9 ( PCSK9 ) underlie ADH. Nevertheless, a proportion of individuals who exhibit the ADH phenotype do not carry mutations in any of these 3 genes. Estimates of the percentage of such cases among the ADH phenotype vary widely. We therefore investigated a large pediatric population with an unequivocal ADH phenotype to assess the molecular basis of hereditary hypercholesterolemia and to define the percentage of individuals with unexplained dyslipidemia. Methods and Results— We enrolled individuals with low-density lipoprotein cholesterol levels above the 95th percentile for age and gender and an autosomal dominant inheritance pattern of hypercholesterolemia from a large referred pediatric cohort of 1430 children. We excluded children with thyroid dysfunction, nephrotic syndrome, autoimmune disease, liver disease, primary biliary cirrhosis, and obesity (body mass index >75th percentile for age and gender), as well as children referred via a cascade screening program and those from families with a known molecular diagnosis. Of the 269 children who remained after the exclusion criteria were applied, 255 (95%) carried a functional mutation ( LDLR , 95%; APOB , 5%). Conclusion— In the vast majority of children with an ADH phenotype, a causative mutation can be identified, strongly suggesting that most of the large-effect genes underlying ADH are known to date. # Clinical Perspective {#article-title-30}Background— Autosomal dominant hypercholesterolemia (ADH) is characterized by elevated low-density lipoprotein cholesterol levels and premature cardiovascular disease. Mutations in the genes encoding for low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), and proprotein convertase subtilisin/kexin 9 (PCSK9) underlie ADH. Nevertheless, a proportion of individuals who exhibit the ADH phenotype do not carry mutations in any of these 3 genes. Estimates of the percentage of such cases among the ADH phenotype vary widely. We therefore investigated a large pediatric population with an unequivocal ADH phenotype to assess the molecular basis of hereditary hypercholesterolemia and to define the percentage of individuals with unexplained dyslipidemia. Methods and Results— We enrolled individuals with low-density lipoprotein cholesterol levels above the 95th percentile for age and gender and an autosomal dominant inheritance pattern of hypercholesterolemia from a large referred pediatric cohort of 1430 children. We excluded children with thyroid dysfunction, nephrotic syndrome, autoimmune disease, liver disease, primary biliary cirrhosis, and obesity (body mass index >75th percentile for age and gender), as well as children referred via a cascade screening program and those from families with a known molecular diagnosis. Of the 269 children who remained after the exclusion criteria were applied, 255 (95%) carried a functional mutation (LDLR, 95%; APOB, 5%). Conclusion— In the vast majority of children with an ADH phenotype, a causative mutation can be identified, strongly suggesting that most of the large-effect genes underlying ADH are known to date.

Molecular Basis of Autosomal Dominant HypercholesterolemiaClinical Perspective

Background— Autosomal dominant hypercholesterolemia (ADH) is characterized by elevated low-density lipoprotein cholesterol levels and premature cardiovascular disease. Mutations in the genes encoding for low-density lipoprotein receptor ( LDLR ), apolipoprotein B ( APOB ), and proprotein convertase subtilisin/kexin 9 ( PCSK9 ) underlie ADH. Nevertheless, a proportion of individuals who exhibit the ADH phenotype do not carry mutations in any of these 3 genes. Estimates of the percentage of such cases among the ADH phenotype vary widely. We therefore investigated a large pediatric population with an unequivocal ADH phenotype to assess the molecular basis of hereditary hypercholesterolemia and to define the percentage of individuals with unexplained dyslipidemia. Methods and Results— We enrolled individuals with low-density lipoprotein cholesterol levels above the 95th percentile for age and gender and an autosomal dominant inheritance pattern of hypercholesterolemia from a large referred pediatric cohort of 1430 children. We excluded children with thyroid dysfunction, nephrotic syndrome, autoimmune disease, liver disease, primary biliary cirrhosis, and obesity (body mass index >75th percentile for age and gender), as well as children referred via a cascade screening program and those from families with a known molecular diagnosis. Of the 269 children who remained after the exclusion criteria were applied, 255 (95%) carried a functional mutation ( LDLR , 95%; APOB , 5%). Conclusion— In the vast majority of children with an ADH phenotype, a causative mutation can be identified, strongly suggesting that most of the large-effect genes underlying ADH are known to date. # Clinical Perspective {#article-title-30}Background— Autosomal dominant hypercholesterolemia (ADH) is characterized by elevated low-density lipoprotein cholesterol levels and premature cardiovascular disease. Mutations in the genes encoding for low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), and proprotein convertase subtilisin/kexin 9 (PCSK9) underlie ADH. Nevertheless, a proportion of individuals who exhibit the ADH phenotype do not carry mutations in any of these 3 genes. Estimates of the percentage of such cases among the ADH phenotype vary widely. We therefore investigated a large pediatric population with an unequivocal ADH phenotype to assess the molecular basis of hereditary hypercholesterolemia and to define the percentage of individuals with unexplained dyslipidemia. Methods and Results— We enrolled individuals with low-density lipoprotein cholesterol levels above the 95th percentile for age and gender and an autosomal dominant inheritance pattern of hypercholesterolemia from a large referred pediatric cohort of 1430 children. We excluded children with thyroid dysfunction, nephrotic syndrome, autoimmune disease, liver disease, primary biliary cirrhosis, and obesity (body mass index >75th percentile for age and gender), as well as children referred via a cascade screening program and those from families with a known molecular diagnosis. Of the 269 children who remained after the exclusion criteria were applied, 255 (95%) carried a functional mutation (LDLR, 95%; APOB, 5%). Conclusion— In the vast majority of children with an ADH phenotype, a causative mutation can be identified, strongly suggesting that most of the large-effect genes underlying ADH are known to date.

Molecular Basis of Autosomal Dominant HypercholesterolemiaClinical Perspective: Assessment in a Large Cohort of Hypercholesterolemic Children

Background— Autosomal dominant hypercholesterolemia (ADH) is characterized by elevated low-density lipoprotein cholesterol levels and premature cardiovascular disease. Mutations in the genes encoding for low-density lipoprotein receptor ( LDLR ), apolipoprotein B ( APOB ), and proprotein convertase subtilisin/kexin 9 ( PCSK9 ) underlie ADH. Nevertheless, a proportion of individuals who exhibit the ADH phenotype do not carry mutations in any of these 3 genes. Estimates of the percentage of such cases among the ADH phenotype vary widely. We therefore investigated a large pediatric population with an unequivocal ADH phenotype to assess the molecular basis of hereditary hypercholesterolemia and to define the percentage of individuals with unexplained dyslipidemia. Methods and Results— We enrolled individuals with low-density lipoprotein cholesterol levels above the 95th percentile for age and gender and an autosomal dominant inheritance pattern of hypercholesterolemia from a large referred pediatric cohort of 1430 children. We excluded children with thyroid dysfunction, nephrotic syndrome, autoimmune disease, liver disease, primary biliary cirrhosis, and obesity (body mass index >75th percentile for age and gender), as well as children referred via a cascade screening program and those from families with a known molecular diagnosis. Of the 269 children who remained after the exclusion criteria were applied, 255 (95%) carried a functional mutation ( LDLR , 95%; APOB , 5%). Conclusion— In the vast majority of children with an ADH phenotype, a causative mutation can be identified, strongly suggesting that most of the large-effect genes underlying ADH are known to date. # Clinical Perspective {#article-title-30}Background— Autosomal dominant hypercholesterolemia (ADH) is characterized by elevated low-density lipoprotein cholesterol levels and premature cardiovascular disease. Mutations in the genes encoding for low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), and proprotein convertase subtilisin/kexin 9 (PCSK9) underlie ADH. Nevertheless, a proportion of individuals who exhibit the ADH phenotype do not carry mutations in any of these 3 genes. Estimates of the percentage of such cases among the ADH phenotype vary widely. We therefore investigated a large pediatric population with an unequivocal ADH phenotype to assess the molecular basis of hereditary hypercholesterolemia and to define the percentage of individuals with unexplained dyslipidemia. Methods and Results— We enrolled individuals with low-density lipoprotein cholesterol levels above the 95th percentile for age and gender and an autosomal dominant inheritance pattern of hypercholesterolemia from a large referred pediatric cohort of 1430 children. We excluded children with thyroid dysfunction, nephrotic syndrome, autoimmune disease, liver disease, primary biliary cirrhosis, and obesity (body mass index >75th percentile for age and gender), as well as children referred via a cascade screening program and those from families with a known molecular diagnosis. Of the 269 children who remained after the exclusion criteria were applied, 255 (95%) carried a functional mutation (LDLR, 95%; APOB, 5%). Conclusion— In the vast majority of children with an ADH phenotype, a causative mutation can be identified, strongly suggesting that most of the large-effect genes underlying ADH are known to date.