Statins for children with familial hypercholesterolemia

Familial hypercholesterolemia and COVID-19: A menacing but treatable vasculopathic condition

SARS-CoV-2 infection continues to cause increased morbidity and mortality, and due to the slow pace of vaccination COVID-19 will probably remain a global burden to health systems for a long time. Unfortunately, the necessary prevention and treatment strategies of COVID-19 have led to restriction measures that are hampering the routine care of common chronic metabolic conditions like hypercholesterolemia. It is of particular concern that during the acute phase of COVID-19, the control of pre-existing metabolic diseases tends to get worse which again increases the risk for complications and a poor outcome in these patients. A significant contributor to these complications is endothelial dysfunction which is associated with COVID-19. This Commentary will discuss the impact of COVID-19 on endothelial function particularly in patients with familial hypercholesterolemia (FH), a metabolic inherited disease known to in itself adversely affect endothelial function. There should be no hesitation to continue with statin therapy in severe hypercholesterolemic patients with COVID-19. We argue that in FH patients with COVID-19 the clinicians need even consider intensifying statin therapy as well as the addition of other lipid-lowering agents, such as proprotein convertase subtilisin/kexin type 9(PCSK9) inhibitors. In contrast to statins, the PCSK9 inhibitors lower lipoprotein(a) [Lp(a)] level, and, accordingly, these latter drugs need to be considered particularly in FH patients with an elevated level of Lp(a). This call applies to the in-hospital stay and also beyond. When considering that the vasculopathic effects of COVID-19 may persist, a long-term follow-up of individualized therapies in FH patients is warranted.

Dyslipidemia and cardiovascular health in childhood nephrotic syndrome

Children with steroid-resistant nephrotic syndrome (SRNS) are exposed to multiple cardiovascular risk factors predisposing them to accelerated atherosclerosis. This risk is negligible in steroid-sensitive nephrotic syndrome, but a substantial proportion of children with SRNS progress to chronic kidney disease, exacerbating the already existing cardiovascular risk. While dyslipidemia is an established modifiable risk factor for cardiovascular disease in adults with NS, it is uncertain to what extent analogous risks exist for children. There is increasing evidence of accelerated atherosclerosis in children with persistently high lipid levels, especially in refractory NS. Abnormalities of lipid metabolism in NS include hypertriglyceridemia and hypercholesterolemia due to elevated apolipoprotein B-containing lipoproteins, decreased lipoprotein lipase and hepatic lipase activity, increased hepatic PCSK9 levels, and reduced hepatic uptake of high-density lipoprotein. Existing guidelines for the management of dyslipidemia in children may be adapted to target lower lipid levels in children with NS, but they will most likely require both lifestyle modifications and pharmacological therapy. While there is a lack of data from randomized controlled trials in children with NS demonstrating the benefit of lipid-lowering drugs, therapies including statins, bile acid sequestrants, fibrates, ezetimibe, and LDL apheresis have all been suggested and/or utilized. However, concerns with the use of lipid-lowering drugs in children include unclear side effect profiles and unknown long-term impacts on neurological development and puberty. The recent introduction of anti-PCSK9 monoclonal antibodies and other therapies targeted to the molecular mechanisms of lipid transport disrupted in NS holds promise for the future treatment of dyslipidemia in NS.

Statins for children with familial hypercholesterolemia

BACKGROUND

Familial hypercholesterolemia is one of the most common inherited metabolic diseases and is an autosomal dominant disorder meaning heterozygotes, or carriers, are affected. Those who are homozygous have severe disease. The average worldwide prevalence of heterozygous familial hypercholesterolemia is at least 1 in 500, although recent genetic epidemiological data from Denmark and next generation sequencing data suggest the frequency may be closer to 1 in 250. Diagnosis of familial hypercholesterolemia in children is based on elevated total cholesterol and low-density lipoprotein cholesterol levels or DNA-based analysis, or both. Coronary atherosclerosis has been detected in men with heterozygous familial hypercholesterolemia as young as 17 years old and in women with heterozygous familial hypercholesterolemia at 25 years old. Since the clinical complications of atherosclerosis occur prematurely, especially in men, lifelong treatment, started in childhood, is needed to reduce the risk of cardiovascular disease. In children with the disease, diet was the cornerstone of treatment but the addition of lipid-lowering medications has resulted in a significant improvement in treatment. Anion exchange resins, such as cholestyramine and colestipol, were found to be effective, but they are poorly tolerated. Since the 1990s studies carried out on children aged 6 to 17 years with heterozygous familial hypercholesterolemia have demonstrated significant reductions in their serum total and low-density lipoprotein cholesterol levels. While statins seem to be safe and well-tolerated in children, their long-term safety in this age group is not firmly established. This is an update of a previously published version of this Cochane Review.

OBJECTIVES

To assess the effectiveness and safety of statins in children with heterozygous familial hypercholesterolemia.

SEARCH METHODS

Relevant studies were identified from the Group's Inborn Errors and Metabolism Trials Register and Medline. Date of most recent search: 04 November 2019.

SELECTION CRITERIA

Randomized and controlled clinical studies including participants up to 18 years old, comparing a statin to placebo or to diet alone.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for inclusion and extracted data.

MAIN RESULTS

We found 26 potentially eligible studies, of which we included nine randomized placebo-controlled studies (1177 participants). In general, the intervention and follow-up time was short (median 24 weeks; range from six weeks to two years). Statins reduced the mean low-density lipoprotein cholesterol concentration at all time points (high-quality evidence). There may be little or no difference in liver function (serum aspartate and alanine aminotransferase, as well as creatinine kinase concentrations) between treated and placebo groups at any time point (low-quality evidence). There may be little or no difference in myopathy (as measured in change in creatinine levels) (low-quality evidence) or clinical adverse events (moderate-quality evidence) with statins compared to placebo. One study on simvastatin showed that this may slightly improve flow-mediated dilatation of the brachial artery (low-quality evidence), and on pravastatin for two years may have induced a regression in carotid intima media thickness (low-quality evidence). No studies reported rhabdomyolysis (degeneration of skeletal muscle tissue) or death due to rhabdomyolysis, quality of life or compliance to study medication.

AUTHORS' CONCLUSIONS

Statin treatment is an effective lipid-lowering therapy in children with familial hypercholesterolemia. Few or no safety issues were identified. Statin treatment seems to be safe in the short term, but long-term safety remains unknown. Children treated with statins should be carefully monitored and followed up by their pediatricians and their care transferred to an adult lipidologist once they reach 18 years of age. Large long-term randomized controlled trials are needed to establish the long-term safety issues of statins.

Factors Affecting Pediatric Dyslipidemia Screening and Treatment

Identification and management of dyslipidemia in childhood can reduce future cardiovascular risk. We performed a retrospective cohort study of children ages 2 to 18 years during 2009 to 2013 to evaluate factors that affect screening and treatment of pediatric dyslipidemia related to 2011 National Heart, Lung, and Blood Institute (NHLBI) guidelines. Logistic regression analysis determined the impact of NHLBI-identified factors on odds of being screened, elevated low-density lipoprotein cholesterol (LDL-C), and receiving pharmacotherapy. A total of 1 736 032 children were included; 113 780 (6.6%) were screened for dyslipidemia. Screening in 9 to 11 year olds increased from 2009 to 2012. Of children screened, 18 801 (16.5%) had elevated LDL-C; 425 (2.3%) were treated pharmacologically. Parental dyslipidemia, diabetes mellitus, chronic kidney disease, Kawasaki disease, human immunodeficiency virus infection, nephrotic syndrome, liver, thyroid, and other endocrine disorders increased odds of screening. Older age, nephrotic syndrome, chronic kidney disease, diabetes mellitus, and hypertension increased odds of having elevated LDL-C and receiving treatment. Pediatric dyslipidemia screening rates remain low.

Achondroplasia: a comprehensive clinical review

Achondroplasia is the most common of the skeletal dysplasias that result in marked short stature (dwarfism). Although its clinical and radiologic phenotype has been described for more than 50 years, there is still a great deal to be learned about the medical issues that arise secondary to this diagnosis, the manner in which these are best diagnosed and addressed, and whether preventive strategies can ameliorate the problems that can compromise the health and well being of affected individuals. This review provides both an updated discussion of the care needs of those with achondroplasia and an exploration of the limits of evidence that is available regarding care recommendations, controversies that are currently present, and the many areas of ignorance that remain.

Effect of atorvastatin on dyslipidemia and carotid intima-media thickness in children with refractory nephrotic syndrome: a randomized controlled trial

BACKGROUND

Dyslipidemia is an important cardiovascular risk factor in steroid-resistant nephrotic syndrome (SRNS). Efficacy of statins for treatment of hyperlipidemia in children with SRNS is unclear.

METHODS

This prospective, randomized, double-blind, placebo-controlled, parallel-group clinical trial enrolled 30 patients with SRNS, aged 5-18 years, with serum low-density lipoprotein cholesterol (LDL-C) levels between 130 and 300 mg/dl, to receive a fixed dose of atorvastatin (n = 15, 10 mg/d) or placebo (n = 15) by block randomization in a 1:1 ratio. Primary outcome was change in serum LDL-C at 12 months. Change in levels of other lipid fractions, carotid intima-media thickness (cIMT), flow-mediated dilation (FMD) of the brachial artery, and adverse events were also evaluated.

RESULTS

At the end of 12 months, atorvastatin was not superior to placebo in reducing plasma LDL-C levels, median percentage reduction 15.8% and 9.5% respectively, in atorvastatin and placebo arms (n = 14 in each; P = 0.40). Apolipoprotein B levels significantly declined with atorvastatin in modified intention-to-treat analysis (P = 0.01) but not in the per-protocol analysis. There was no significant effect on other lipid fractions, cIMT and FMD. Adverse events were similar between groups. Change in serum albumin was negatively associated with change in serum LDL-C, very low-density lipoprotein cholesterol, total cholesterol, triglyceride, and apolipoprotein B (P < 0.001), irrespective of receiving atorvastatin, age, gender, body mass index, and serum creatinine.

CONCLUSIONS

Atorvastatin, administered at a fixed daily dose of 10 mg, was not beneficial in lowering lipid levels in children with SRNS; rise in serum albumin was associated with improvement in dyslipidemia.

Secondary Dyslipidemia In Obese Children - Is There Evidence For Pharmacological Treatment?

BACKGROUND

Long-term safety, effectiveness and criteria for treatment with statins in children are still unclear in clinical practice. There is very limited evidence for the use of medication to treat children with dyslipidemia secondary to obesity who do not respond well to lifestyle modification.

OBJECTIVE

Systematic review of randomized clinical trials of statin use to treat children and adolescents with dyslipidemia secondary to obesity.

METHODS

We performed a search in PubMed, EMBASE, Bireme, Web of Science, Cochrane Library, SciELO, and LILACS for data to evaluate the effect of statins on: improvement of surrogate markers of coronary artery disease in clinical outcomes of adulthood; increased serum levels of total cholesterol (TC), low-density lipoprotein cholesterol (LDL-C) and apolipropotein B (APOB); and decreased serum levels of high-density lipoprotein cholesterol (HDL-C) from inception to February 2016. Participants were children and adolescents.

RESULTS

Of the 16793 potentially relevant citations recovered from the electronic databases, no randomized clinical trials fulfilled the inclusion criteria for children with dyslipidemia secondary to obesity.

CONCLUSIONS

We found no specific evidence to consider statins in the treatment of hypercholesterolemia secondary to obesity in children. The usual practice of extrapolating findings from studies in genetic dyslipidemia ignores the differences in long-term cardiovascular risks and the long-term drug treatment risks, when compared to recommendation of lifestyle changes. Randomized clinical trials are needed to understand drug treatment in dyslipidemia secondary to obesity.

Cholesterol screening and statin use in children: a literature review

Atherosclerosis begins in childhood. Fatty streaks, the earliest precursor of atherosclerotic lesions, have been found in the coronary arteries of children of 2 years of age. Hypercholesterolaemia is a risk factor for coronary artery disease. Hypercholesterolaemia can be either primary, when it is characteristic of the main disease, or secondary when it occurs as a result of either a disease process or drug treatment. Given the risk of vascular disease, including myocardial infarction (MI), cerebrovascular accidents (CVA, also known as strokes), peripheral vascular disease (PVD) and ruptured aortic aneurysm, which may follow atherosclerosis, it is important to prevent or slow the early development of atherosclerotic lesions. This prevention necessitates the control of key risk factors such hypercholesterolaemia, dyslipidaemia, hypertension etc. However, at what point this prevention ought to occur, and in what form, is uncertain. Using pharmacological primary prevention for hypercholesterolaemia in the paediatric population is controversial. In an adult patient, hypercholesterolaemia warrants the initiation of a statin. Statins, also known as hydroxymethylglutaryl co-enzyme A inhibitors (or HMG-CoA inhibitors) act by altering cholesterol metabolism. In the paediatric population, the clinical course of vascular disease and the effect of altering this clinical course are less certain. This article reviews the published literature on hypercholesterolaemia in children and the use of statins as a treatment for dyslipidaemia in children. The US National Cholesterol Expert Panel on Integrated Guidelines for Cardiovascular Health and Risk Reduction in Children and Adolescents 2012 guidelines (NCEP guidelines) regarding the recognition and treatment of childhood dyslipidaemia are reviewed.

Efficacy and Safety of Pitavastatin in Children and Adolescents with Familial Hypercholesterolemia in Japan and Europe

Aim: Children with Familial Hypercholesterolemia (FH) are widely prescribed statins, and it has been suggested that the effects of statins differ among ethnicities. We compared the efficacy and safety of pitavastatin in children and adolescents with FH in clinical trials conducted in Japan and Europe.

Methods: Low-density lipoprotein cholesterol (LDL-C) reductions, adjusted for confounding factors, and safety were compared between the studies in Japan and Europe. In the Japanese study, 14 males with heterozygous FH, aged 11.8 ± 1.6 years, were randomized to 52-week double-blind treatment with 1 or 2 mg/day pitavastatin. In the European study, 106 children and adolescents with high risk hyperlipidemia (103 heterozygous FH), aged 10.6 ± 2.9 years, were randomized to 12-week double-blind treatment with 1, 2 or 4 mg/day pitavastatin or placebo; 84 of these patients and 29 new patients participated in a 52-week open-label extension study.

Results: Age, body weight and baseline LDL-C were identified as factors influencing LDL-C reduction. There were no significant differences in the adjusted mean percentage reduction in LDL-C in Japanese and European children by pitavastatin (24.5% and 23.6%, respectively at 1 mg/day and 33.5% and 30.8%, respectively at 2 mg/day). Pitavastatin was well tolerated without any difference in the frequency or nature of adverse events between the treatment groups, or between the studies.

Conclusion: There were no significant differences between the efficacy or safety of pitavastatin in Japanese and European children and adolescents with FH, suggesting no relevant ethnic differences in the safety or efficacy of pitavastatin.

Statins for children with familial hypercholesterolemia

BACKGROUND

Familial hypercholesterolemia is one of the most common inherited metabolic diseases and is an autosomal dominant disorder meaning heterozygotes, or carriers, are affected. Those who are homozygous have severe disease. The average worldwide prevalence of heterozygous familial hypercholesterolemia is at least 1 in 500, although recent genetic epidemiological data from Denmark and next generation sequencing data suggest the frequency may be closer to 1 in 250. Diagnosis of familial hypercholesterolemia in children is based on elevated total cholesterol and low-density lipoprotein cholesterol levels or DNA-based analysis, or both. Coronary atherosclerosis has been detected in men with heterozygous familial hypercholesterolemia as young as 17 years old and in women with heterozygous familial hypercholesterolemia at 25 years old. Since the clinical complications of atherosclerosis occur prematurely, especially in men, lifelong treatment, started in childhood, is needed to reduce the risk of cardiovascular disease. In children with the disease, diet was the cornerstone of treatment but the addition of lipid-lowering medications has resulted in a significant improvement in treatment. Anion exchange resins, such as cholestyramine and colestipol, were found to be effective, but they are poorly tolerated. Since the 1990s studies carried out on children aged 6 to 17 years with heterozygous familial hypercholesterolemia have demonstrated significant reductions in their serum total and low-density lipoprotein cholesterol levels. While statins seem to be safe and well-tolerated in children, their long-term safety in this age group is not firmly established. This is an update of a previously published version of this Cochane Review.

OBJECTIVES

To assess the effectiveness and safety of statins in children with heterozygous familial hypercholesterolemia.

SEARCH METHODS

Relevant studies were identified from the Group's Inborn Errors and Metabolism Trials Register and Medline.Date of most recent search: 20 February 2017.

SELECTION CRITERIA

Randomized and controlled clinical studies including participants up to 18 years old, comparing a statin to placebo or to diet alone.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed studies for inclusion and extracted data.

MAIN RESULTS

We found 26 potentially eligible studies, of which we included nine randomized placebo-controlled studies (1177 participants). In general, the intervention and follow-up time was short (median 24 weeks; range from six weeks to two years). Statins reduced the mean low-density lipoprotein cholesterol concentration at all time points (moderate quality evidence). Serum aspartate and alanine aminotransferase, as well as creatinine kinase concentrations, did not differ between treated and placebo groups at any time point (low quality evidence). The risks of myopathy (low quality evidence) and clinical adverse events (moderate quality evidence) were very low and also similar in both groups. In one study simvastatin was shown to improve flow-mediated dilatation of the brachial artery (low quality evidence), and in another study treatment with pravastatin for two years induced a significant regression in carotid intima media thickness (low quality evidence).

AUTHORS' CONCLUSIONS

Statin treatment is an effective lipid-lowering therapy in children with familial hypercholesterolemia. No significant safety issues were identified. Statin treatment seems to be safe in the short term, but long-term safety remains unknown. Children treated with statins should be carefully monitored and followed up by their pediatricians and their care transferred to an adult lipidologist once they reach 18 years of age. Large long-term randomized controlled trials are needed to establish the long-term safety issues of statins.

Statin-Associated Myopathy in a Pediatric Preventive Cardiology Practice

OBJECTIVES

To describe muscle-related statin adverse effects in real-world pediatric practice.

STUDY DESIGN

Using prospectively collected quality improvement data from a pediatric preventive cardiology practice, we compared serum creatine kinase (CK) levels among patients prescribed and not prescribed statins, and pre-/poststatin initiation. Multivariable mixed-effect models were constructed accounting for repeated measures, examining the effect of statins on log-transformed CK (lnCK) levels adjusted for age, sex, weight, season, insurance type, and race/ethnicity.

RESULTS

Among 1501 patients seen over 3.5 years, 474 patients (14?±?4 years, 47% female) had at least 1 serum CK measured. Median (IQR) CK levels of patients prescribed (n?=?188 patients, 768 CK measurements) and not prescribed statins (n?=?351 patients, 682 CK measurements) were 107 (83) IU/L and 113 (81) IU/L, respectively. In multivariable-adjusted models, lnCK levels did not differ based on statin use (??=?0.02 [SE 0.05], P?=?.7). Among patients started on statins (n?=?86, 130 prestatin and 292 poststatin CK measurements), median CK levels did not differ in adjusted models (? for statin use on lnCK?=?.08 [SE .07], P?=?.2). There was a clinically insignificant increase in CK over time (??=?.08 [SE .04], P?=?.04 per year). No muscle symptoms or rhabdomyolysis were reported among patients with high CK levels.

CONCLUSIONS

In a real-world practice, pediatric patients using statins did not experience higher CK levels, nor was there a meaningful CK increase with statin initiation. These data suggest the limited utility to checking CK in the absence of symptoms, supporting current guidelines.

The UK Paediatric Familial Hypercholesterolaemia Register: preliminary data

BACKGROUND

The National Institute for Health and Care Excellence 2008 guidelines on the treatment and management of familial hypercholesterolaemia (FH) recommend that children with FH should be considered for statin treatment by the age of 10 years. The Paediatric FH Register was established in 2012 to collect baseline and long-term follow-up data on all children with FH in the UK.

METHODS

Paediatricians and adult lipidologists have been invited to enter baseline data on any child with a clinical diagnosis of FH using an electronic capture record.

RESULTS

Baseline data is on 232 children (50% boys, 80% Caucasian), with an untreated mean (SD) total cholesterol of 7.61 (1.48) mmol/L and low-density lipoprotein cholesterol (LDL-C) of 5.67 (1.46) mmol/L. Overall 111/232 (47.8%) of the children were on statins. Children over the age of 10 years at the most recent follow-up were twice as likely to be on statin treatment than those under 10 years (57.6% (102/177) vs 23.1% (9/39), p=0.00009). In both age groups, those subsequently on statin treatment had significantly higher diagnostic total and LDL-C (overall 6.01 (1.46) mmol/L vs 5.31 (1.37) mmol/L, p=0.00007), and had stronger evidence of a family history of early coronary heart disease (CHD) in parent or first-degree relative (overall 28.4% vs 19.0%, p=0.09). In statin-treated children LDL-C level was reduced by 35% (2.07 (1.38) mmol/L) compared with a reduction of 5.5% (0.29 (0.87) mmol/L), p=0.0001 in those not treated. None of those on statin had measured plasma levels of creatine kinase, alanine aminotransferase and AST indicative of statin toxicity (ie, >2.5 times the upper limit of the normal range).

CONCLUSIONS

The data indicates that treatment decisions in children with FH are appropriately based on a stronger family history of CHD and higher LDL-C.

Correlates of Achieving Statin Therapy Goals in Children and Adolescents with Dyslipidemia

OBJECTIVE

To determine the real-world effectiveness of statins and impact of baseline factors on low-density lipoprotein cholesterol (LDL-C) reduction among children and adolescents.

STUDY DESIGN

We analyzed data prospectively collected from a quality improvement initiative in the Boston Children's Hospital Preventive Cardiology Program. We included patients ≤21 years of age initiated on statins between September 2010 and March 2014. The primary outcome was first achieving goal LDL-C, defined as <130 mg/dL, or <100 mg/dL with high-level risk factors (eg, diabetes, etc). Cox proportional hazards models were used to assess the impact of baseline clinical and lifestyle factors.

RESULTS

Among the 1521 pediatric patients evaluated in 3813 clinical encounters over 3.5 years, 97 patients (6.3%) were started on statin therapy and had follow-up data (median age 14 [IQR 7] years, 54% were female, and 24% obese, 62% with at least one lifestyle risk factor). The median baseline LDL-C was 215 (IQR 78) mg/dL, and median follow-up after starting statin was 1 (IQR 1.3) year. The cumulative probability of achieving LDL-C goal within 1 year was 60% (95% CI 47-69). A lower probability of achieving LDL-C goals was associated with male sex (HR 0.5 [95% CI 0.3-0.8]) and higher baseline LDL-C (HR 0.92 [95% CI 0.87-0.98] per 10 mg/dL), but not age, body mass index percentile, lifestyle factors, or family history.

CONCLUSIONS

The majority of pediatric patients started on statins reached LDL-C treatment goals within 1 year. Male patients and those with greater baseline LDL-C were less likely to be successful and may require increased support.

Pediatric Statin Administration: Navigating a Frontier with Limited Data

Increasingly, children and adolescents with dyslipidemia qualify for pharmacologic intervention. As they are for adults, 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors (statins) are the mainstay of pediatric dyslipidemia treatment when lifestyle modifications have failed. Despite the overall success of these drugs, the magnitude of variability in dose-exposure-response profiles contributes to adverse events and treatment failure. In children, the cause of treatment failures remains unclear. This review describes the updated guidelines for screening and management of pediatric dyslipidemia and statin disposition pathway to assist the provider in recognizing scenarios where alterations in dosage may be warranted to meet patients' specific needs.

Screening for Familial Hypercholesterolemia in Children: What Can We Learn From Adult Screening Programs?

Familial hypercholesterolemia (FH), an autosomal dominant atherosclerotic disease, is a common monogenic subtype of cardiovascular disease. Patients with FH suffer an increased risk of early onset heart disease. Early identification of abnormally elevated cholesterol signpost clinicians to interventions that will significantly decrease risk of related morbidity and mortality. Cascade genetic testing can subsequently identify at-risk relatives. Accordingly, a number of screening approaches have been implemented for FH in countries including the UK and the Netherlands. However, incomplete identification of cases remains a challenge. Moreover, the potential for early intervention is now raising questions about the value of implementing universal cholesterol screening approaches that focus on children. In this report, we briefly discuss the potential benefit of such screening. Additionally, we submit that ever increasing genome technological capability will force a discussion of including genetic tests in these screening programs. We discuss the opportunities and challenges presented by such an approach. We close with recommendations that the success of such screening endeavors will rely on a better integrated practice model in public health genomics that bridges stakeholders including practitioners in primary care, clinical genetics and public health.

Optimizing Treatment of Familial Hypercholesterolemia in Children and Adolescents

Cardiovascular disease (CVD) is still the most prominent cause of death and morbidity in the world, and one of the major risk factors for developing CVD is hypercholesterolemia. Familial hypercholesterolemia (FH) is a dominantly inherited disorder characterized by markedly elevated plasma low-density lipoprotein cholesterol and premature coronary heart disease. Currently, several treatment options are available for children with FH. Lifestyle adjustments are the first step in treatment. If this is not sufficient, statins are the preferred initial pharmacological therapy and they have been proven effective and safe. However, treatment goals are often not achieved and, hence, there is a need for novel treatment options. Currently, several options are being studied in adults and first results are promising. However, studies in children are still to be awaited.

Familial hypercholesterolaemia in children and adolescents: gaining decades of life by optimizing detection and treatment

Familial hypercholesterolaemia (FH) is a common genetic cause of premature coronary heart disease (CHD). Globally, one baby is born with FH every minute. If diagnosed and treated early in childhood, individuals with FH can have normal life expectancy. This consensus paper aims to improve awareness of the need for early detection and management of FH children. Familial hypercholesterolaemia is diagnosed either on phenotypic criteria, i.e. an elevated low-density lipoprotein cholesterol (LDL-C) level plus a family history of elevated LDL-C, premature coronary artery disease and/or genetic diagnosis, or positive genetic testing. Childhood is the optimal period for discrimination between FH and non-FH using LDL-C screening. An LDL-C ≥5 mmol/L (190 mg/dL), or an LDL-C ≥4 mmol/L (160 mg/dL) with family history of premature CHD and/or high baseline cholesterol in one parent, make the phenotypic diagnosis. If a parent has a genetic defect, the LDL-C cut-off for the child is ≥3.5 mmol/L (130 mg/dL). We recommend cascade screening of families using a combined phenotypic and genotypic strategy. In children, testing is recommended from age 5 years, or earlier if homozygous FH is suspected. A healthy lifestyle and statin treatment (from age 8 to 10 years) are the cornerstones of management of heterozygous FH. Target LDL-C is <3.5 mmol/L (130 mg/dL) if >10 years, or ideally 50% reduction from baseline if 8–10 years, especially with very high LDL-C, elevated lipoprotein(a), a family history of premature CHD or other cardiovascular risk factors, balanced against the long-term risk of treatment side effects. Identifying FH early and optimally lowering LDL-C over the lifespan reduces cumulative LDL-C burden and offers health and socioeconomic benefits. To drive policy change for timely detection and management, we call for further studies in the young. Increased awareness, early identification, and optimal treatment from childhood are critical to adding decades of healthy life for children and adolescents with FH.

The genetics of familial hypercholesterolemia and emerging therapies

Familial hypercholesterolemia (FH) results in very high levels of atherogenic low-density lipoprotein (LDL) cholesterol from the time of birth. Mutations of the genes encoding for the LDL receptor, apolipoprotein B and proprotein convertase subtilisin/kexin type 9, are causes for this autosomal dominant inherited condition. Heterozygous FH is very common, while homozygous FH is rare. Affected individuals can experience premature cardiovascular disease; most homozygous patients experience this before the age of 20 years. Since effective LDL cholesterol lowering therapies are available, morbidity and mortality are decreased. The use of statins is the first choice in therapy; combining other lipid-lowering medications is recommended to lower LDL cholesterol sufficiently. In some cases, lipoprotein apheresis is necessary. In heterozygous FH, these measures are effective to lower LDL cholesterol, but in severe cases and in homozygous FH there remains an unmet need. Emerging therapies, such as the recently approved microsomal triglyceride transfer protein inhibitor and the apolipoprotein B antisense oligonucleotide, might offer further options for these patients with very high cardiovascular risk. Early diagnosis and early treatment are important to reduce cardiovascular events and premature death.

Familial hypercholesterolemia

BACKGROUND

Familial hypercholesterolemia (FH) is an autosomal dominant-inherited genetic disorder that leads to elevated blood cholesterol levels. FH may present as severely elevated total cholesterol and low density lipoprotein (LDL) cholesterol levels or as premature coronary heart disease (CHD).

METHODS

This review presents information on the disease and on the effects of drug treatment and lifestyle changes.

RESULTS

Routine lipid testing should identify most patients with FH. Once an index case is identified, testing should be offered to family members. Early diagnosis and aggressive treatment with therapeutic lifestyle changes and statins can prevent premature CHD and other atherosclerotic sequelae in patients with FH.

CONCLUSION

Emerging therapies such as LDL apheresis and novel therapeutic agents may be useful in patients with homozygous FH or treatment-resistant FH. Liver transplantation is the only effective therapy for severe cases of homozygous FH.