Screening for familial hypercholesterolaemia in childhood: Avon Longitudinal Study of Parents and Children (ALSPAC)

Overcoming the real and imagined barriers to cholesterol screening in pediatrics

Recent guidance by the United States Preventive Services Task Force has renewed the debate surrounding the benefits of pediatric lipid screening. This commentary reviews the evolution of the pediatric lipid screening recommendations in the United States, followed by an exploration of real and imagined challenges that prevent optimal cholesterol screening rates in children. Real challenges substantively prevent the uptake of these guidelines into practice; imagined challenges, such as identifying the best age to screen, are often context-dependent and can also be surmounted. Experiences from other countries identify potential facilitators to improving screening and additional barriers. Implementation science provides guidance on overcoming the real barriers, translating evidence-based recommendations into clinical practice, and informing the next wave of solutions to overcome these challenges.

Should Familial Hypercholesterolaemia Be Included in the UK Newborn Whole Genome Sequencing Programme?

PURPOSE OF REVIEW

The UK National Health Service (NHS) has recently announced a Newborn Genomes Programme (NGP) to identify infants with treatable inherited disorders using whole genome sequencing (WGS). Here, we address, for familial hypercholesterolaemia (FH), the four principles that must be met for the inclusion of a disorder in the NGP.

RECENT FINDINGS

Principle A: There is strong evidence that the genetic variants causing FH can be reliably detected. Principle B: A high proportion of individuals who carry an FH-causing variant are likely to develop early heart disease if left undiagnosed and not offered appropriate treatment. Principle C: Early intervention has been shown to lead to substantially improved outcomes in children with FH. Principle D: The recommended interventions are equitably accessible for all. FH meets all the Wilson and Jungner criteria for inclusion in a screening programme, and it also meets all four principles and therefore should be included in the Newborn Genomes Programme.

Risk Factors for Premature Coronary Heart Disease in Women Compared to Men: Systematic Review and Meta-Analysis

Background: We aimed to systematically examine literature on the prevalence of known modifiable and nonmodifiable risk factors for premature coronary heart disease (PCHD) in women compared with men. Materials and Methods: PubMed, CINAHL, Embase, and Web of Science databases were searched. Review protocol is registered in PROSPERO (CRD42020173216). Quality was assessed using the National Heart, Lung, and Blood Institute tool. Review Manager 5.3 was used for meta-analysis. Effect sizes were expressed as odds ratio (OR) and mean differences/standardized mean differences (SMD) with 95% confidence intervals (CIs) for categorical and continuous variables. Results: In this PCHD cohort (age <65 years), the mean age of presentation in women was 3 years older than men. Women had higher total cholesterol (SMD 0.11; 95% CI 0.00 to 0.23) and higher high-density lipoprotein cholesterol (SMD 0.49; 95% CI 0.29 to 0.69). Women were more likely to have hypertension (OR 1.51, 95% CI 1.42 to 1.60), diabetes mellitus (OR 1.78, 95% CI 1.55 to 2.04), obesity (OR 1.33, 95% CI 1.24 to 1.42), metabolic syndrome (OR 3.73, 95% CI 1.60 to 8.69), stroke (OR 1.63, 95% CI 1.51 to 1.77), peripheral vascular disorder (OR 1.67, 95% CI 1.43 to 1.96), and depression (OR 2.29, 95% CI 1.96 to 2.67). Women were less likely to be smokers (OR 0.60, 95% CI 0.55 to 0.66), have reported alcohol intake (OR 0.36, 95% CI 0.33 to 0.40), and reported use of illicit drug (OR 0.32, 95% CI 0.16 to 0.62). Conclusions: Risk factor profile in PCHD has a clear sex difference that supports early, aggressive, holistic, but sex-specific, approach to prevention.

Screening for Lipid Disorders in Children and Adolescents: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

Importance

Lipid screening in childhood and adolescence can lead to early dyslipidemia diagnosis. The long-term benefits of lipid screening and subsequent treatment in this population are uncertain.

Objective

To review benefits and harms of screening and treatment of pediatric dyslipidemia due to familial hypercholesterolemia (FH) and multifactorial dyslipidemia.

Data Sources

MEDLINE and the Cochrane Central Register of Controlled Trials through May 16, 2022; literature surveillance through March 24, 2023.

Study Selection

English-language randomized clinical trials (RCTs) of lipid screening; recent, large US cohort studies reporting diagnostic yield or screen positivity; and RCTs of lipid-lowering interventions.

Data Extraction and Synthesis

Single extraction, verified by a second reviewer. Quantitative synthesis using random-effects meta-analysis.

Main Outcomes and Measures

Health outcomes, diagnostic yield, intermediate outcomes, behavioral outcomes, and harms.

Results

Forty-three studies were included (n = 491 516). No RCTs directly addressed screening effectiveness and harms. Three US studies (n = 395 465) reported prevalence of phenotypically defined FH of 0.2% to 0.4% (1:250 to 1:500). Five studies (n = 142 257) reported multifactorial dyslipidemia prevalence; the prevalence of elevated total cholesterol level (≥200 mg/dL) was 7.1% to 9.4% and of any lipid abnormality was 19.2%. Ten RCTs in children and adolescents with FH (n = 1230) demonstrated that statins were associated with an 81- to 82-mg/dL greater mean reduction in levels of total cholesterol and LDL-C compared with placebo at up to 2 years. Nonstatin-drug trials showed statistically significant lowering of lipid levels in FH populations, but few studies were available for any single drug. Observational studies suggest that statin treatment for FH starting in childhood or adolescence reduces long-term cardiovascular disease risk. Two multifactorial dyslipidemia behavioral counseling trials (n = 934) demonstrated 3- to 6-mg/dL greater reductions in total cholesterol levels compared with the control group, but findings did not persist at longest follow-up. Harms reported in the short-term drug trials were similar in the intervention and control groups.

Conclusions and Relevance

No direct evidence on the benefits or harms of pediatric lipid screening was identified. While multifactorial dyslipidemia is common, no evidence was found that treatment is effective for this condition. In contrast, FH is relatively rare; evidence shows that statins reduce lipid levels in children with FH, and observational studies suggest that such treatment has long-term benefit for this condition.

A Machine Learning Model to Aid Detection of Familial Hypercholesterolemia

Background

People with monogenic familial hypercholesterolemia (FH) are at an increased risk of premature coronary heart disease and death. With a prevalence of 1:250, FH is relatively common; but currently there is no population screening strategy in place and most carriers are identified late in life, delaying timely and cost-effective interventions.

Objectives

The purpose of this study was to derive an algorithm to identify people with suspected monogenic FH for subsequent confirmatory genomic testing and cascade screening.

Methods

A least absolute shrinkage and selection operator logistic regression model was used to identify predictors that accurately identified people with FH in 139,779 unrelated participants of the UK Biobank. Candidate predictors included information on medical and family history, anthropometric measures, blood biomarkers, and a low-density lipoprotein cholesterol (LDL-C) polygenic score (PGS). Model derivation and evaluation were performed in independent training and testing data.

Results

A total of 488 FH variant carriers were identified using whole-exome sequencing of the low-density lipoprotein receptor, apolipoprotein B, apolipoprotein E, proprotein convertase subtilisin/kexin type 9 genes. A 14-variable algorithm for FH was derived, with an area under the curve of 0.77 (95% CI: 0.71-0.83), where the top 5 most important variables included triglyceride, LDL-C, apolipoprotein A1 concentrations, self-reported statin use, and LDL-C PGS. Excluding the PGS as a candidate feature resulted in a 9-variable model with a comparable area under the curve: 0.76 (95% CI: 0.71-0.82). Both multivariable models (w/wo the PGS) outperformed screening-prioritization based on LDL-C adjusted for statin use.

Conclusions

Detecting individuals with FH can be improved by considering additional predictors. This would reduce the sequencing burden in a 2-stage population screening strategy for FH.

[Advantages of Universal Early Childhood Screening for Familial Hypercholesterolaemia in Germany]

Hintergrund Kardiovaskuläre Ereignisse sind die wichtigste Mortalitätsursache in der westlichen Welt. Die familiäre Hypercholesterinämie (FH) zeichnet sich durch erhöhte low-density Lipoprotein-Cholesterin- und Gesamtcholesterin-Spiegel im peripheren Blut aus. Die FH beruht zumeist auf einer genetischen Veränderung im LDL-Rezeptorgen und gehört zu den häufigsten monogenen Erkrankungen. Bei der homozygoten Form ist die Mortalität aufgrund kardiovaskulärer Ereignisse im Kindes- und Jugendalter extrem hoch. Auch die heterozygote Form der FH führt unbehandelt früh zu kardiovaskulären Ereignissen und sollte frühzeitig diagnostiziert und behandelt werden, um eine Atherosklerose zu vermeiden. Die präventive und sichere Anwendung einer medikamentösen Lipidsenkung konnte für Kinder gezeigt werden.

Methode Literatursuche in Cochrane library, Medline, NCBI databases.

Ergebnisse Anders als in europäischen Nachbarländern wurde in Deutschland im Kindesalter kein universelles Screening auf diese häufige Erkrankung etabliert, obwohl dies in den Leitlinien gefordert wird. In der vorliegenden Arbeit wird die Literatur untersucht hinsichtlich der Kausalität der Erkrankung, der Therapie im Kindesalter sowie hinsichtlich des Zutreffens klassischer und modifizierter Kriterien für das Durchführen eines vorgeschlagenen universellen FH-Screenings zum 5. Geburtstag mit anschließendem reversen Kaskadenscreening bei Verwandten.

Schlussfolgerung Die Autoren plädieren für die Einführung eines universellen FH-Screenings in Deutschland zur Vorsorgeuntersuchung U9 mit 5 Jahren. Eine Analyse anhand des Goldstandards klassischer Kriterien nach Wilson und Jungner sowie anhand im zeitlichen Kontext angepasster Kriterien zeigt die Vorteile eines universellen frühkindlichen FH-Screening. Dieses kann präventiv das kardiovaskuläre Risiko absenken, das Fortschreiten der Atherosklerose verlangsamen und zu niedrigeren Inzidenzen von Schlaganfall und Herzinfarkt im Erwachsenenalter beitragen. Neben den diagnostizierten FH-Kindern können auch deren betroffene Verwandte erkannt werden.

Genetic Spectrum of Familial Hypercholesterolaemia in the Malaysian Community: Identification of Pathogenic Gene Variants Using Targeted Next-Generation Sequencing

Familial hypercholesterolaemia (FH) is caused by mutations in lipid metabolism genes, predominantly in low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), proprotein convertase subtilisin/kexin-type 9 (PCSK9) and LDL receptor adaptor protein 1 (LDLRAP1). The prevalence of genetically confirmed FH and the detection rate of pathogenic variants (PV) amongst clinically diagnosed patients is not well established. Targeted next-generation sequencing of LDLR, APOB, PCSK9 and LDLRAP1 was performed on 372 clinically diagnosed Malaysian FH subjects. Out of 361 variants identified, 40 of them were PV (18 = LDLR, 15 = APOB, 5 = PCSK9 and 2 = LDLRAP1). The majority of the PV were LDLR and APOB, where the frequency of both PV were almost similar. About 39% of clinically diagnosed FH have PV in PCSK9 alone and two novel variants of PCSK9 were identified in this study, which have not been described in Malaysia and globally. The prevalence of genetically confirmed potential FH in the community was 1:427, with a detection rate of PV at 0.2% (12/5130). About one-fourth of clinically diagnosed FH in the Malaysian community can be genetically confirmed. The detection rate of genetic confirmation is similar between potential and possible FH groups, suggesting a need for genetic confirmation in index cases from both groups. Clinical and genetic confirmation of FH index cases in the community may enhance the early detection of affected family members through family cascade screening.

Detecting Familial hypercholesterolemia in children and adolescents: potential and challenges

Background

It is now well established that atherosclerosis begins in childhood and evolves through adolescence and young adulthood, ultimately resulting in myocardial infarction and stroke in adults.

Main test

Childhood is a critical phase during which atherosclerosis may begin to develop; in the presence of familial hypercholesterolemia, lifelong elevation of Low Density Lipoprotein cholesterol levels greatly accelerates atherosclerosis. These concepts, which have been largely developed from epidemiologic evidence, have not always been simple to implement in the paediatric clinical practice.

The purpose of this article is to briefly review but also to highlight the rationale, the motivation and the methods in the process of identifying children and adolescents with familial hypercholesterolemia, an often hidden but very important genetic disease.

Genetic testing for familial hypercholesterolemia-past, present, and future

In the early 1980s, the Nobel Prize winning cellular and molecular work of Mike Brown and Joe Goldstein led to the identification of the LDL receptor gene as the first gene where mutations cause the familial hypercholesterolemia (FH) phenotype. We now know that autosomal dominant monogenic FH can be caused by pathogenic variants of three additional genes (APOB/PCSK9/APOE) and that the plasma LDL-C concentration and risk of premature coronary heart disease differs according to the specific locus and associated molecular cause. It is now possible to use next-generation sequencing to sequence all exons of all four genes, processing 96 patient samples in one sequencing run, increasing the speed of test results, and reducing costs. This has resulted in the identification of not only many novel FH-causing variants but also some variants of unknown significance, which require further evidence to classify as pathogenic or benign. The identification of the FH-causing variant in an index case can be used as an unambiguous and rapid test for other family members. An FH-causing variant can be found in 20-40% of patients with the FH phenotype, and we now appreciate that in the majority of patients without a monogenic cause, a polygenic etiology for their phenotype is highly likely. Compared with those with a monogenic cause, these patients have significantly lower risk of future coronary heart disease. The use of these molecular genetic diagnostic methods in the characterization of FH is a prime example of the utility of precision or personalized medicine.

Cardiorespiratory fitness, fatness, and the acute blood pressure response to exercise in adolescence

OBJECTIVE

Exaggerated exercise blood pressure (BP) is associated with cardiovascular risk factors in adolescence. Cardiorespiratory fitness and adiposity (fatness) are independent contributors to cardiovascular risk, but their interrelated associations with exercise BP are unknown. This study aimed to determine the relationships between fitness, fatness, and the acute BP response to exercise in a large birth cohort of adolescents.

METHODS

2292 adolescents from the Avon Longitudinal Study of Parents and Children (aged 17.8 ± 0.4 years, 38.5% male) completed a sub-maximal exercise step test that allowed fitness (VO2 max ) to be determined from workload and heart rate using a validated equation. Exercise BP was measured immediately on test cessation and fatness calculated as the ratio of total fat mass to total body mass measured by DXA.

RESULTS

Post-exercise systolic BP decreased stepwise with tertile of fitness (146 (18); 142 (17); 141 (16) mmHg) but increased with tertile of fatness (138 (15); 142 (16); 149 (18) mmHg). In separate models, fitness and fatness were associated with post-exercise systolic BP adjusted for sex, age, height, smoking, and socioeconomic status (standardized β: -1.80, 95%CI: -2.64, -0.95 mmHg/SD and 4.31, 95%CI: 3.49, 5.13 mmHg/SD). However, when fitness and fatness were included in the same model, only fatness remained associated with exercise BP (4.65, 95%CI: 3.69, 5.61 mmHg/SD).

CONCLUSION

Both fitness and fatness are associated with the acute BP response to exercise in adolescence. The fitness-exercise BP association was not independent of fatness, implying the cardiovascular protective effects of cardiorespiratory fitness may only be realized with more favorable body composition.

Prevalence of Familial Hypercholesterolemia Among the General Population and Patients With Atherosclerotic Cardiovascular Disease

Background:

Contemporary studies suggest that familial hypercholesterolemia (FH) is more frequent than previously reported and increasingly recognized as affecting individuals of all ethnicities and across many regions of the world. Precise estimation of its global prevalence and prevalence across World Health Organization regions is needed to inform policies aiming at early detection and atherosclerotic cardiovascular disease (ASCVD) prevention. The present study aims to provide a comprehensive assessment and more reliable estimation of the prevalence of FH than hitherto possible in the general population (GP) and among patients with ASCVD.

Methods:

We performed a systematic review and meta-analysis including studies reporting on the prevalence of heterozygous FH in the GP or among those with ASCVD. Studies reporting gene founder effects and focused on homozygous FH were excluded. The search was conducted through Medline, Embase, Cochrane, and Global Health, without time or language restrictions. A random-effects model was applied to estimate the overall pooled prevalence of FH in the general and ASCVD populations separately and by World Health Organization regions.

Results:

From 3225 articles, 42 studies from the GP and 20 from populations with ASCVD were eligible, reporting on 7 297 363 individuals/24 636 cases of FH and 48 158 patients/2827 cases of FH, respectively. More than 60% of the studies were from Europe. Use of the Dutch Lipid Clinic Network criteria was the commonest diagnostic method. Within the GP, the overall pooled prevalence of FH was 1:311 (95% CI, 1:250–1:397; similar between children [1:364] and adults [1:303], P =0.60; across World Health Organization regions where data were available, P =0.29; and between population-based and electronic health records–based studies, P =0.82). Studies with ≤10 000 participants reported a higher prevalence (1:200–289) compared with larger cohorts (1:365–407; P <0.001). The pooled prevalence among those with ASCVD was 18-fold higher than in the GP (1:17 [95% CI, 1:12–1:24]), driven mainly by coronary artery disease (1:16; [95% CI, 1:12–1:23]). Between-study heterogeneity was large ( I 2 >95%). Tests assessing bias were nonsignificant ( P >0.3).

Conclusions:

With an overall prevalence of 1:311, FH is among the commonest genetic disorders in the GP, similarly present across different regions of the world, and is more frequent among those with ASCVD. The present results support the advocacy for the institution of public health policies, including screening programs, to identify FH early and to prevent its global burden.

Familial hypercholesterolemia: is it time to separate monogenic from polygenic familial hypercholesterolemia?

PURPOSE OF REVIEW

This review explores the concepts of monogenic and the so-called polygenic familial hypercholesterolemia and how the identification of familial hypercholesterolemia as a monogenic condition and its separation from polygenic primary hypercholesterolemia may have implications for clinical practice.

RECENT FINDINGS

Through genetic testing, a mutation in any of the three known autosomal dominant familial hypercholesterolemia-causing genes is found in 60-80% of cases with a clinical diagnosis of definite familial hypercholesterolemia. As individuals with a polygenic basis for their hypercholesterolemia do not follow the same inheritance pattern observed in monogenic familial hypercholesterolemia, the use of family-based cascade screening in individuals with a polygenic origin is not recommend, as only 30% of relatives have an elevated LDL-C compared to the 50% in monogenic families. The presence of a causative monogenic mutation associates the highest cardiovascular risk vs. not having a mutation or having a polygenic background, providing prognostic information independent of LDL-C. It may also help assess intensity of interventions. Treatment adherence also seems to be higher after monogenic confirmation of hypercholesterolemia.

SUMMARY

Knowledge about the genetic status of an individual with clinical familial hypercholesterolemia (monogenic vs. polygenic) can provide a more informed understanding to evaluating risk, managing disease and opportunities for screening strategies.

Widening the spectrum of genetic testing in familial hypercholesterolaemia: Will it translate into better patient and population outcomes?

Familial hypercholesterolaemia (FH) is caused by pathogenic variants in LDLR, APOB or PCSK9. Impaired low-density lipoprotein (LDL) receptor function leads to decreased LDL catabolism and premature atherosclerotic cardiovascular disease (ASCVD). Thousands of LDLR variants are known, but assignation of pathogenicity requires accurate phenotyping, family studies and assessment of LDL receptor function. Precise, genetic diagnosis of FH using targeted next generation sequencing allows for optimal treatment, distinguishing FH from pathogenically distinct disorders requiring different treatment. Polygenic hypercholesterolaemia resulting from an accumulation of LDL cholesterol-raising single nucleotide polymorphisms (SNPs) could also be suspected by this approach. Similarly, ASCVD risk could be estimated by broader sequencing of cholesterol and non-cholesterol-related genes. Both of these areas require further research. The clinical management of FH, focusing on the primary or secondary prevention of ASCVD, has been boosted by PCSK9 inhibitor therapy. The efficacy of PCSK9 inhibitors in homozygous FH may be partly predicted by the LDLR variants. While expanded genetic testing in FH is clinically useful in providing an accurate diagnosis and enabling cost-effective testing of relatives, further research is needed to establish its value in improving clinical outcomes.

Universal screening for familial hypercholesterolemia in children: The Slovenian model and literature review

BACKGROUND AND AIMS

Familial hypercholesterolemia (FH) is arguably the most common monogenic disorder in humans, but severely under-diagnosed. Individuals with untreated FH have an over 10-fold elevated risk of cardiovascular complications as compared to unaffected individuals; early diagnosis and timely management substantially reduce this risk. Slovenia has gradually implemented the program of universal FH screening in pre-school children, consisting of a two step approach: (1) universal hypercholesterolemia screening in pre-school children at the primary care level; (2) genetic FH screening in children referred to the tertiary care level according to clinical guidelines (with additional cascade screening of family members). The program is presented in detail.

METHODS

We analyzed retrospective data (2012-2016), to assess the efficiency of the universal FH screening program. In that period, 280 children (59.3% female) were referred to our center through the program for having TC > 6 mmol/L (231.7 mg/dL) or >5 mmol/L (193.1 mg/dL), with a positive family history of premature cardiovascular complications at the universal hypercholesterolemia screening.

RESULTS

170 (57.1% female) of them were fully genotyped, 44.7% had an FH disease-causing variant (28.8% in LDLR gene, 15.9% in APOB, none in PCSK9), one patient was LIPA positive, and 40.9% of the remaining patients carried an ApoE4 isoform; genetic analysis is still ongoing for one-third of the referred patients. For almost every child with confirmed FH, one parent had highly probable FH.

CONCLUSIONS

FH was confirmed in almost half of the referred children, detected through the universal screening for hypercholesterolemia.

Improving the detection of familial hypercholesterolaemia

Familial hypercholesterolaemia (FH) is a dominantly inherited disorder of low-density lipoprotein (LDL) catabolism, which if untreated causes lifelong elevated LDL-cholesterol (LDL-c), accelerated atherosclerosis and premature cardiovascular disease. Recent evidence suggests the prevalence of heterozygous FH is ∼1:220, making FH the most common autosomal dominant condition. Lowering LDL-c with statin and lifestyle therapy reduces the risk of cardiovascular events. Furthermore, proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors significantly lower LDL-c in addition to statin therapy, and early outcome data suggest improved vascular outcomes with these agents in FH patients in addition to statins. However, the vast majority of people with FH still remain undiagnosed. The onus is on clinicians to identify kindreds with FH, as PCSK9 inhibitors, although expensive, are funded for patients with FH in Australia. Multiple strategies for detecting FH have been proposed. The detection of index cases can be achieved through applying electronic screening tools to general practice databases, universal screening of children during immunisation, and targeted screening of patients with premature cardiovascular disease. Advances in genomic technology have decreased costs of genetic testing, improved the understanding of the pathogenesis of FH and facilitated cascade screening. However, awareness of FH amongst clinicians and the general public still requires optimisation. This review outlines recent advances in FH detection, including emerging strategies and challenges for the next decade.

Universal screening at age 1-2 years as an adjunct to cascade testing for familial hypercholesterolaemia in the UK: A cost-utility analysis

BACKGROUND AND AIMS

Familial hypercholesterolaemia (FH) is widely underdiagnosed. Cascade testing (CT) of relatives has been shown to be feasible, acceptable and cost-effective in the UK, but requires a supply of index cases. Feasibility of universal screening (US) at age 1-2 years was recently demonstrated. We examined whether this would be a cost-effective adjunct to CT in the UK, given the current and plausible future undiagnosed FH prevalence.

METHODS

Seven cholesterol and/or mutation-based US ± reverse cascade testing (RCT) alternatives were compared with no US in an incremental analysis with a healthcare perspective. A decision model was used to estimate costs and outcomes for cohorts exposed to the US component of each strategy. RCT case ascertainment was modelled using recent UK CT data, and probabilistic Markov models estimated lifetime costs and health outcomes for the cohorts screened under each alternative. 1000 Monte Carlo simulations were run for each model, and average outcomes reported. Further uncertainty was explored deterministically. Threshold analysis investigated the association between undiagnosed FH prevalence and cost-effectiveness.

RESULTS

A strategy involving cholesterol screening followed by diagnostic genetic testing and RCT was the most cost-effective modelled (incremental cost-effectiveness ratio (ICER) versus no US £12,480/quality adjusted life year (QALY); probability of cost-effectiveness 96·8% at £20,000/QALY threshold). Cost-effectiveness was robust to both deterministic sensitivity analyses and threshold analyses that modelled ongoing case ascertainment at theoretical maximum levels.

CONCLUSIONS

These findings support implementation of universal cholesterol screening followed by diagnostic genetic testing and RCT for FH, under a UK conventional willingness-to-pay threshold.

Knowns and unknowns in the care of pediatric familial hypercholesterolemia

Familial hypercholesterolemia (FH) is a common genetic disorder that causes elevated LDL cholesterol levels from birth. Untreated FH accelerates atherosclerosis and predisposes individuals to premature coronary artery disease (CAD) in adulthood. Mendelian randomization studies have demonstrated that LDL cholesterol has both a causal and cumulative effect on the risk of CAD. This supports clinical recommendations that children with FH commence pharmacological treatment from the age of 8 to 10 years, to reduce the burden of hypercholesterolemia. Worldwide, the majority of children with FH remain undiagnosed. Recent evidence suggests that the frequency of FH is at least 1 in 250 and this constitutes a public health issue. We review and identify the knowns and unknowns concerning the detection and management of pediatric FH that impact on the developing model of care for this condition.