Cardiovascular outcomes in patients with homozygous familial hypercholesterolaemia on lipoprotein apheresis initiated during childhood: long-term follow-up of an international cohort from two registries.

BACKGROUND: Homozygous familial hypercholesterolaemia (HoFH) is a rare genetic disease characterised by extremely high plasma LDL cholesterol from birth, causing atherosclerotic cardiovascular disease at a young age. Lipoprotein apheresis in combination with lipid-lowering drugs effectively reduce LDL cholesterol, but long-term health outcomes of such treatment are unknown. We aimed to investigate the long-term cardiovascular outcomes associated with lipoprotein apheresis initiated in childhood or adolescence. METHODS: In this cohort study, data were drawn from the HoFH International Clinical Collaboration (HICC) and the international registry for Children with Homozygous Hypercholesterolemia on Lipoprotein Apheresis (CHAIN). An overall cohort included patients diagnosed with HoFH aged 0-18 years who were alive and in follow-up between Jan 1, 2010, and Nov 8, 2021, and whose high plasma LDL cholesterol concentrations made them eligible for lipoprotein apheresis. To compare cardiovascular outcomes, patients who initiated lipoprotein apheresis in childhood (lipoprotein apheresis group) and patients who only received lipid-lowering drugs (pharmacotherapy-only group) were matched by sex and untreated plasma LDL cholesterol concentrations. The primary outcome was a composite of cardiovascular death, myocardial infarction, ischaemic stroke, percutaneous coronary intervention, coronary artery bypass grafting, aortic valve replacement, peripheral artery disease, carotid endarterectomy, angina pectoris, and supra-aortic or aortic stenosis (collectively referred to as atherosclerotic cardiovascular disease), for which survival analyses were performed in the matched cohort. Cox regression analyses were used to compare disease-free survival between cohorts and to calculate hazard ratio (HR) and 95% CI adjusted for sex, age at diagnosis, untreated plasma LDL cholesterol concentration, and number of lipid-lowering therapies other than lipoprotein apheresis. FINDINGS: The overall cohort included 404 patients with a median age at diagnosis of 6·0 years (IQR 3·0-9·5) and median untreated plasma LDL cholesterol of 17·8 mmol/L (14·7-20·8). The matched cohorts included 250 patients (125 patients per group), with a median untreated LDL cholesterol of 17·2 mmol/L (14·8-19·7). Mean reduction in plasma LDL cholesterol concentrations between baseline and final follow-up was greater in the lipoprotein apheresis group (-55% [95% CI -60 to -51] vs -31% [-36 to -25]; p<0·0001). Patients in the lipoprotein apheresis group had longer atherosclerotic cardiovascular disease-free survival (adjusted HR 0·52 [95% CI 0·32-0·85]) and longer cardiovascular death-free survival (0·0301 [0·0021-0·4295]). Cardiovascular death was more common in the pharmacotherapy-only group than in the lipoprotein apheresis group (ten [8%] vs one [1%]; p=0·010), whereas median age at coronary artery bypass grafting was lower in the lipoprotein apheresis group than in the pharmacotherapy-only group (15·0 years [IQR 12·0-24·0] vs 30·5 years [19·0-33·8]; p=0·037). INTERPRETATION: Among patients with HoFH, lipoprotein apheresis initiated during childhood and adolescence is associated with reduced long-term risk of atherosclerotic cardiovascular disease and death, and clear benefits of early initiation of high-frequency treatment on reducing plasma cholesterol were found. Consensus recommendations are now needed to guide more widespread and timely use of lipoprotein apheresis for children with HoFH, and research is required to further optimise treatment and ensure benefits of early and aggressive treatment delivery are balanced against effects on quality of life. FUNDING: Amsterdam University Medical Centers, Location Academic Medical Center; Perelman School of Medicine at the University of Pennsylvania; European Atherosclerosis Society; and the US National Heart, Lung, and Blood Institute, National Institutes of Health.

Clinical practice recommendations on lipoprotein apheresis for children with homozygous familial hypercholesterolaemia: An expert consensus statement from ERKNet and ESPN.

Homozygous familial hypercholesterolaemia is a life-threatening genetic condition, which causes extremely elevated LDL-C levels and atherosclerotic cardiovascular disease very early in life. It is vital to start effective lipid-lowering treatment from diagnosis onwards. Even with dietary and current multimodal pharmaceutical lipid-lowering therapies, LDL-C treatment goals cannot be achieved in many children. Lipoprotein apheresis is an extracorporeal lipid-lowering treatment, which is used for decades, lowering serum LDL-C levels by more than 70% directly after the treatment. Data on the use of lipoprotein apheresis in children with homozygous familial hypercholesterolaemia mainly consists of case-reports and case-series, precluding strong evidence-based guidelines. We present a consensus statement on lipoprotein apheresis in children based on the current available evidence and opinions from experts in lipoprotein apheresis from over the world. It comprises practical statements regarding the indication, methods, treatment goals and follow-up of lipoprotein apheresis in children with homozygous familial hypercholesterolaemia and on the role of lipoprotein(a) and liver transplantation.

Current and emerging monoclonal antibodies for treating familial hypercholesterolemia in children.

INTRODUCTION: Heterozygous familial hypercholesterolemia (HeFH) is a common genetic disorder caused by pathogenic variants in the LDL-C metabolism. Lifelong exposure to elevated LDL-C levels leads to a high risk of premature cardiovascular disease. To reduce that risk, children with HeFH should be identified and treated with lipid-lowering therapy. The cornerstone consists of statins and ezetimibe, but not in all patients this lowers the LDL-C levels to treatment targets. For these patients, more intensive lipid-lowering therapy is needed. AREAS COVERED: In this review, we provide an overview of the monoclonal antibodies which are currently available or being tested for treating HeFH in childhood. EXPERT OPINION: Monoclonal antibodies that inhibit PCSK9 are first in line lipid-lowering treatment options if oral statin and ezetimibe therapy are insufficient, due to intolerance or very high baseline LDL-C levels. Both evolocumab and alirocumab have been shown to be safe and effective in children with HeFH. For children, evolocumab has been registered from the age of 10 years old and alirocumab from the age of 8 years old. The costs of these new agents are much higher than oral therapy, which makes it important to only use them in a selected patient population.

Evolocumab Treatment in Pediatric Patients With Homozygous Familial Hypercholesterolemia: Pooled Data From Three Open-Label Studies.

BACKGROUND: Pediatric patients with homozygous familial hypercholesterolemia (HoFH) have an increased risk of atherosclerotic cardiovascular disease and difficulty meeting low-density lipoprotein cholesterol (LDL-C) goals. In this post hoc analysis, we evaluated pooled safety and efficacy data from 3 studies in pediatric patients with HoFH treated with the PCSK9 (proprotein convertase subtilisin/kexin type 9) monoclonal antibody inhibitor evolocumab. METHODS: Patients with HoFH aged 10 to 17 years received treatment with open-label evolocumab 420 mg subcutaneously monthly or biweekly in the TAUSSIG, RAMAN, or HAUSER-OLE clinical studies. All patients received background statins with or without ezetimibe. Study duration ranged from 12 to 260 weeks. The primary end point was treatment-emergent adverse events per 100 patient-years. Efficacy end points were changes from baseline to week 12 in lipids and PCSK9. RESULTS: Of the 39 patients in the pooled analysis, 69.2% were males, median age was 13.0 years, and 79.5% (31/39) had genotyped HoFH with LDLR pathogenic variants. Overall, median exposure to evolocumab was 18.2 (Q1, Q3: 3.0, 18.5) months. Treatment-emergent adverse events with an exposure-adjusted patient incidence rate of ≥5% were upper respiratory tract infection (6.6%), influenza (5.2%), and acne (5.0%) per 100 patient-years. Exposure-adjusted patient incidence of serious treatment-emergent adverse events was 13.3% per 100 patient-years. Excluding 4 patients receiving lipoprotein apheresis, week 12 median percentage change from baseline in LDL-C was -2.9% (Q1, Q3: -21.7, 1.5); however, 42.9% (15/35) of patients achieved ≥15% reduction in LDL-C from baseline. Residual LDLR (LDL receptor) activity was not associated with a reduction in LDL-C. CONCLUSIONS: In this pooled data analysis from 3 studies in pediatric patients with HoFH, evolocumab was well tolerated, with no new safety signals reported. These safety findings are consistent with findings from previous studies of evolocumab. Patients showed marked variability in LDL-C reduction. Results from this pooled analysis support guidelines suggesting a trial of PCSK9 inhibitor therapy regardless of estimated residual LDLR function. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT01624142, NCT03403374, and NCT02624869.

Alirocumab in Pediatric Patients With Heterozygous Familial Hypercholesterolemia: A Randomized Clinical Trial.

Importance: Many pediatric patients with heterozygous familial hypercholesterolemia (HeFH) cannot reach recommended low-density lipoprotein cholesterol (LDL-C) concentrations on statins alone and require adjunct lipid-lowering therapy (LLT); the use of alirocumab in pediatric patients requires evaluation. Objective: To assess the efficacy of alirocumab in pediatric patients with inadequately controlled HeFH. Design, Setting, and Participants: This was a phase 3, randomized clinical trial conducted between May 2018 and August 2022 at 43 centers in 24 countries. Pediatric patients aged 8 to 17 years with HeFH, LDL-C 130 mg/dL or greater, and receiving statins or other LLTs were included. Following consecutive enrollment into dosing cohorts, 25 of 99 patients screened for dosing every 2 weeks (Q2W) failed screening; 25 of 104 patients screened for dosing every 4 weeks (Q4W) failed screening. A total of 70 of 74 Q2W patients (95%) and 75 of 79 Q4W patients (95%) completed the double-blind period. Interventions: Patients were randomized 2:1 to subcutaneous alirocumab or placebo and Q2W or Q4W. Dosage was based on weight (40 mg for Q2W or 150 mg for Q4W if <50 kg; 75 mg for Q2W or 300 mg for Q4W if ≥50 kg) and adjusted at week 12 if LDL-C was 110 mg/dL or greater at week 8. After the 24-week double-blind period, patients could receive alirocumab in an 80-week open-label period. Main Outcomes and Measures: The primary end point was percent change in LDL-C from baseline to week 24 in each cohort. Results: Among 153 patients randomized to receive alirocumab or placebo (mean [range] age, 12.9 [8-17] years; 87 [56.9%] female), alirocumab showed statistically significant reductions in LDL-C vs placebo in both cohorts at week 24. Least squares mean difference in percentage change from baseline was -43.3% (97.5% CI, -56.0 to -30.7; P < .001) Q2W and -33.8% (97.5% CI, -46.4 to -21.2; P < .001) Q4W. Hierarchical analysis of secondary efficacy end points demonstrated significant improvements in other lipid parameters at weeks 12 and 24 with alirocumab. Two patients receiving alirocumab Q4W experienced adverse events leading to discontinuation. No significant difference in adverse event incidence was observed between treatment groups. Open-label period findings were consistent with the double-blind period. Conclusions and Relevance: The findings in this study indicate that alirocumab Q2W or Q4W significantly may be useful for reducing LDL-C and other lipid parameters and be well tolerated in pediatric patients with HeFH inadequately controlled with statins. Trial Registration: ClinicalTrials.gov Identifier: NCT03510884.

Breaking the chains of lipoprotein lipase deficiency: A pediatric perspective on the efficacy and safety of Volanesorsen.

RATIONALE: Lipoprotein lipase (LPL) deficiency, a rare inherited metabolic disorder, is characterized by high triglyceride (TG) levels and life-threatening acute pancreatitis. Current treatment for pediatric patients involves a lifelong severely fat-restricted diet, posing adherence challenges. Volanesorsen, an EMA-approved RNA therapy for adults, effectively reduces TG levels by decreasing the production of apolipoprotein C-III. This 96-week observational open-label study explores Volanesorsen's safety and efficacy in a 13-year-old female with LPL deficiency. METHODS: The patient, with a history of severe TG elevations, 53 hospital admissions, and life-threatening recurrent pancreatitis despite dietary restrictions, received weekly subcutaneous Volanesorsen injections. We designed a protocol for this investigator-initiated study, primarily focusing on changes in fasting TG levels and hospital admissions. RESULTS: While the injections caused occasional pain and swelling, no other adverse events were observed. TG levels decreased during treatment, with more measurements below the pancreatitis risk threshold compared to pre-treatment. No hospital admissions occurred in the initial 14 months of treatment, contrasting with 21 admissions in the 96 weeks before. In the past 10 months, two pancreatitis episodes may have been linked to dietary noncompliance. Dietary restrictions were relaxed, increasing fat intake by 65% compared to baseline. While not fully reflected in the PedsQL, both parents and the patient narratively reported an improved quality of life. CONCLUSION: This study demonstrates, for the first time, that Volanesorsen is tolerated in a pediatric patient with severe LPL deficiency and effectively lowers TG levels, preventing life-threatening complications. This warrants consideration for expanded access in this population.

Beyond early LDL cholesterol lowering to prevent coronary atherosclerosis in familial hypercholesterolaemia.

AIMS: Familial hypercholesterolaemia (FH) patients are subjected to a high lifetime exposure to low density lipoprotein cholesterol (LDL-C), despite use of lipid-lowering therapy (LLT). This study aimed to quantify the extent of subclinical atherosclerosis and to evaluate the association between lifetime cumulative LDL-C exposure and coronary atherosclerosis in young FH patients. METHODS AND RESULTS: Familial hypercholesterolaemia patients, divided into a subgroup of early treated (LLT initiated <25 years) and late treated (LLT initiated ≥25 years) patients, and an age- and sex-matched unaffected control group, underwent coronary CT angiography (CCTA) with artificial intelligence-guided analysis. Ninety genetically diagnosed FH patients and 45 unaffected volunteers (mean age 41 ± 3 years, 51 (38%) female) were included. Familial hypercholesterolaemia patients had higher cumulative LDL-C exposure (181 ± 54 vs. 105 ± 33 mmol/L ∗ years) and higher prevalence of coronary plaque compared with controls (46 [51%] vs. 10 [22%], OR 3.66 [95%CI 1.62-8.27]). Every 75 mmol/L ∗ years cumulative exposure to LDL-C was associated with a doubling in per cent atheroma volume (total plaque volume divided by total vessel volume). Early treated patients had a modestly lower cumulative LDL-C exposure compared with late treated FH patients (167 ± 41 vs. 194 ± 61 mmol/L ∗ years; P = 0.045), without significant difference in coronary atherosclerosis. Familial hypercholesterolaemia patients with above-median cumulative LDL-C exposure had significantly higher plaque prevalence (OR 3.62 [95%CI 1.62-8.27]; P = 0.001), compared with patients with below-median exposure. CONCLUSION: Lifetime exposure to LDL-C determines coronary plaque burden in FH, underlining the need of early as well as potent treatment initiation. Periodic CCTA may offer a unique opportunity to monitor coronary atherosclerosis and personalize treatment in FH.

This study reveals that young patients with familial hypercholesterolaemia (FH), as compared with individuals without FH, have a higher build-up of coronary artery plaque, linked directly to their increased lifetime exposure to LDL cholesterol. Genetically confirmed FH patients have a higher coronary plaque burden than those without FH, with every 75 mmol/L ∗ years increase in lifetime cumulative LDL cholesterol exposure resulting in a two-fold increase in total plaque volume. Early and potent LDL cholesterol lowering treatments are crucial for FH patients to prevent future cardiovascular diseases.

CTCA in children with severe heterozygous familial hypercholesterolaemia: Screening for subclinical atherosclerosis.

Familial hypercholesterolemia (FH) is one of the most common genetically inherited disorders in the world. Children with severe heterozygous FH (HeFH), i.e. untreated low-density lipoprotein cholesterol (LDL-C) levels above the 90th percentile for age and sex among FH mutation carriers, can have LDL-C levels that overlap levels of children with homozygous FH (HoFH), but treatment regimen and cardiovascular follow-up to prevent cardiovascular disease are less intensive in children with severe HeFH. In children with HoFH, subclinical atherosclerosis can already be present using computed tomography coronary angiography (CTCA). The question remains whether this is also the case in children with severe HeFH who have a high exposure to elevated LDL-C levels from birth onwards as well. We calculated the cumulative LDL-C exposure (CEtotal [mmol]) in four children with severe HeFH and performed computed tomography coronary angiography (CTCA). These children, aged 13, 14, 15 and 18 years, had CEtotal of 71.3, 97.8, 103.6 and 136.1 mmol, respectively. None of them showed abnormalities on cardiovascular imaging, despite high LDL-C exposure. The results of this study, do not give us an indication to recommend performing CTCA routinely in children with severe HeFH.

Evolocumab in paediatric heterozygous familial hypercholesterolaemia: cognitive function during 80 weeks of open-label extension treatment.

AIMS: PCSK9 inhibition intensively lowers low density lipoprotein cholesterol and is well tolerated in adults and paediatric patients with familial hypercholesterolaemia (FH). HAUSER-RCT showed that 24 weeks of treatment with evolocumab in paediatric patients did not affect cognitive function. This study determined the effects of 80 additional weeks of evolocumab treatment on cognitive function in paediatric patients with heterozygous FH. METHODS AND RESULTS: HAUSER-OLE was an 80-week open-label extension of HAUSER-RCT, a randomized, double-blind, 24-week trial evaluating the efficacy and safety of evolocumab in paediatric patients (ages 10-17 years) with FH. During the OLE, all patients received monthly 420 mg subcutaneous evolocumab injections. Tests of psychomotor function, attention, visual learning, and executive function were administered at baseline and Weeks 24 and 80 of the OLE. Changes over time were analysed descriptively and using analysis of covariance. Cohen's d statistic was used to evaluate the magnitude of treatment effects. Analysis of covariance results indicated no decrease in performance across visits during 80 weeks of evolocumab treatment for Groton Maze Learning, One Card Learning accuracy, Identification speed, or Detection speed (all P > 0.05). Performance on all tasks was similar for those who received placebo or evolocumab in the RCT (all P > 0.05). For all tests, the least square mean differences between patients who received placebo vs. evolocumab in the parent study were trivial (all Cohen's d magnitude < 0.2). CONCLUSION: In paediatric patients with FH, 80 weeks of open-label evolocumab treatment had no negative impact on cognitive function. REGISTRATION: ClinicalTrials.gov identifier: NCT02624869.

Some children are born with a genetic disorder that causes high cholesterol, which leads to heart disease. Children with high cholesterol can be treated with evolocumab, a medication that lowers blood cholesterol. Because cholesterol is important for development and adequate function of the brain, there is a concern that lowering cholesterol in children may affect mental ability. In this study, we tested whether treating children with evolocumab for 80 weeks affected mental ability in performing several tasks. A battery of tests that measure executive function (Groton Maze Learning Test), visual learning (One Card Learning Test), visual attention (Identification Test), and psychomotor function (Detection Test) showed no decrease in performance across visits during 80 weeks of evolocumab treatment. Performance on all tasks was similar for the children who received placebo for the first 24 weeks then received evolocumab for an additional 80 weeks (placebo/evolocumab) and those who received evolocumab for 24 weeks then received evolocumab for an additional 80 weeks (evolocumab/evolocumab).

Evinacumab for Pediatric Patients With Homozygous Familial Hypercholesterolemia.

BACKGROUND: Homozygous familial hypercholesterolemia (HoFH) is a rare genetic disorder characterized by severely elevated low-density lipoprotein cholesterol (LDL-C) levels due to profoundly defective LDL receptor (LDLR) function. Given that severely elevated LDL-C starts in utero, atherosclerosis often presents during childhood or adolescence, creating a largely unmet need for aggressive LDLR-independent lipid-lowering therapies in young patients with HoFH. Here we present the first evaluation of the efficacy and safety of evinacumab, a novel LDLR-independent lipid-lowering therapy, in pediatric patients with HoFH from parts A and B of a 3-part study. METHODS: The phase 3, part B, open-label study treated 14 patients 5 to 11 years of age with genetically proven HoFH (true homozygotes and compound heterozygotes) with LDL-C >130 mg/dL, despite optimized lipid-lowering therapy (including LDLR-independent apheresis and lomitapide), with intravenous evinacumab 15 mg/kg every 4 weeks. RESULTS: Evinacumab treatment rapidly and durably (through week 24) decreased LDL-C with profound reduction in the first week, with a mean (SE) LDL-C reduction of -48.3% (10.4%) from baseline to week 24. ApoB (mean [SE], -41.3% [9.0%]), non-high-density lipoprotein cholesterol (-48.9% [9.8%]), and total cholesterol (-49.1% [8.1%]) were similarly decreased. Treatment-emergent adverse events were reported in 10 (71.4%) patients; however, only 2 (14.3%) reported events that were considered to be treatment-related (nausea and abdominal pain). One serious treatment-emergent adverse event of tonsillitis occurred (n=1), but this was not considered treatment-related. CONCLUSIONS: Evinacumab constitutes a new treatment for pediatric patients with HoFH and inadequately controlled LDL-C despite optimized lipid-lowering therapy, lowering LDL-C levels by nearly half in these extremely high-risk and difficult-to-treat individuals. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT04233918.

Dyslipidaemia as a target for atherosclerotic cardiovascular disease prevention in children with type 1 diabetes: lessons learned from familial hypercholesterolaemia.

In the last few decades, atherosclerotic cardiovascular disease (ASCVD) risk has decreased dramatically among individuals affected by familial hypercholesterolaemia (FH) as a result of the early initiation of statin treatment in childhood. Contemporaneously important improvements in care for people with diabetes have also been made, such as the prevention of mortality from acute diabetic complications. However, individuals with type 1 diabetes still have a two to eight times higher risk of death than the general population. In the last 20 years, a few landmark studies on excess mortality in people with type 1 diabetes, in particular young adults, have been published. Although these studies were carried out in different populations, all reached the same conclusion: individuals with type 1 diabetes have a pronounced increased risk of ASCVD. In this review, we address the role of lipid abnormalities in the development of ASCVD in type 1 diabetes and FH. Although type 1 diabetes and FH are different diseases, lessons could be learned from the early initiation of statins in children with FH, which may provide a rationale for more stringent control of dyslipidaemia in children with type 1 diabetes.

Clinical practice recommendations on lipoprotein apheresis for children with homozygous familial hypercholesterolemia: an expert consensus statement from ERKNet and ESPN.

Homozygous familial hypercholesterolaemia is a life-threatening genetic condition, which causes extremely elevated LDL-C levels and atherosclerotic cardiovascular disease very early in life. It is vital to start effective lipid-lowering treatment from diagnosis onwards. Even with dietary and current multimodal pharmaceutical lipid-lowering therapies, LDL-C treatment goals cannot be achieved in many children. Lipoprotein apheresis is an extracorporeal lipid-lowering treatment, which is well established since three decades, lowering serum LDL-C levels by more than 70% per session. Data on the use of lipoprotein apheresis in children with homozygous familial hypercholesterolaemia mainly consists of case-reports and case-series, precluding strong evidence-based guidelines. We present a consensus statement on lipoprotein apheresis in children based on the current available evidence and opinions from experts in lipoprotein apheresis from over the world. It comprises practical statements regarding the indication, methods, treatment targets and follow-up of lipoprotein apheresis in children with homozygous familial hypercholesterolaemia and on the role of lipoprotein(a) and liver transplantation.

Lipoprotein(a) and carotid intima-media thickness in children with familial hypercholesterolaemia in the Netherlands: a 20-year follow-up study.

BACKGROUND: Elevated lipoprotein(a) and familial hypercholesterolaemia are both independent risk conditions for cardiovascular disease. Although signs of atherosclerosis can be observed in children with familial hypercholesterolaemia, it is unknown whether elevated lipoprotein(a) is an additional risk factor for atherosclerosis in these young patients. Therefore, we aimed to assess the contribution of lipoprotein(a) concentrations to arterial wall thickening (as measured by carotid intima-media thickness) in children with familial hypercholesterolaemia who were followed up into adulthood. METHODS: We conducted a 20-year follow-up study of 214 children (aged 8-18 years) with heterozygous familial hypercholesterolaemia who were randomly assigned in a statin trial in Amsterdam (Netherlands) between Dec 7, 1997, and Oct 4, 1999. At baseline, and at 2, 10, and 20 years thereafter, blood samples were taken and carotid intima-media thickness was measured. Linear mixed-effects models were used to evaluate the association between lipoprotein(a) and carotid intima-media thickness during follow-up. We adjusted for sex, age, corrected LDL-cholesterol, statin use, and BMI. FINDINGS: Our study population comprised 200 children who had a carotid intima-media thickness measurement and a measured lipoprotein(a) concentration from at least one visit available. Mean age at baseline was 13·0 years (SD 2·9), 106 (53%) children were male, and 94 (47%) were female. At baseline, median lipoprotein(a) concentration was 18·5 nmol/L (IQR 8·7-35·5) and mean carotid intima-media thickness was 0·4465 mm (SD 0·0496). During follow-up, higher lipoprotein(a) concentrations contributed significantly to progression of carotid intima-media thickness (ß adjusted 0·0073 mm per 50 nmol/L increase in lipoprotein(a) [95% CI 0·0013-0·0132]; p=0·017). INTERPRETATION: Our findings suggest that lipoprotein(a) concentrations contribute significantly to arterial wall thickening in children with familial hypercholesterolaemia who were followed-up until adulthood, suggesting that lipoprotein(a) is an independent and additional risk factor for early atherosclerosis in those already at increased risk. Lipoprotein(a) measurement in young patients with familial hypercholesterolaemia is crucial to identify those at potentially highest risk for cardiovascular disease. FUNDING: Silence Therapeutics.

2023 Update on European Atherosclerosis Society Consensus Statement on Homozygous Familial Hypercholesterolaemia: new treatments and clinical guidance.

This 2023 statement updates clinical guidance for homozygous familial hypercholesterolaemia (HoFH), explains the genetic complexity, and provides pragmatic recommendations to address inequities in HoFH care worldwide. Key strengths include updated criteria for the clinical diagnosis of HoFH and the recommendation to prioritize phenotypic features over genotype. Thus, a low-density lipoprotein cholesterol (LDL-C) >10 mmol/L (>400 mg/dL) is suggestive of HoFH and warrants further evaluation. The statement also provides state-of-the art discussion and guidance to clinicians for interpreting the results of genetic testing and for family planning and pregnancy. Therapeutic decisions are based on the LDL-C level. Combination LDL-C-lowering therapy-both pharmacologic intervention and lipoprotein apheresis (LA)-is foundational. Addition of novel, efficacious therapies (i.e. inhibitors of proprotein convertase subtilisin/kexin type 9, followed by evinacumab and/or lomitapide) offers potential to attain LDL-C goal or reduce the need for LA. To improve HoFH care around the world, the statement recommends the creation of national screening programmes, education to improve awareness, and management guidelines that account for the local realities of care, including access to specialist centres, treatments, and cost. This updated statement provides guidance that is crucial to early diagnosis, better care, and improved cardiovascular health for patients with HoFH worldwide.

Cost-effectiveness and Return on Investment of a Nationwide Case-Finding Program for Familial Hypercholesterolemia in Children in the Netherlands.

Importance: The Netherlands is one of the few countries that has a long-term history of active screening for familial hypercholesterolemia (FH), enabling health-economic analyses. Objective: To investigate cost-effectiveness and the return on investment (ROI) of a nationwide cascade case-finding and preventive treatment program starting with identification of FH in children and treatment, from both a societal and health care perspective. Design, Setting, and Participants: Cascade case-finding and early preventive treatment were modeled to simulate the progression of disease and costs of 10-year-olds suspected of having heterozygous FH over a lifetime. The model consisted of 3 health states: alive without coronary heart disease (CHD), alive with CHD, and deceased. Mendelian randomization analysis was used to quantify the risk of a first CHD event as a function of age and total lifetime exposure to low-density lipoprotein cholesterol. Cost-effectiveness was defined as €20 000 ($21 800) per QALYs (quality-adjusted life-years) gained, using incremental cost-effectiveness ratios (ICERs). All future benefits and costs were discounted annually by 1.5% and 4%, respectively. Interventions: The study compared 2 strategies: (1) cascade screening and initiation of treatment with statins in children (mean age, 10 years) and (2) no screening, later detection, and treatment. Main Outcomes and Measures: Outcome of interest included cost, detection, and successful treatment of FH in terms of life-years gained and QALYs. The clinical and cost outputs for each model in the 2 scenarios (early detection and treatment and later detection and treatment) were totaled to determine the overall cost-effectiveness and ROI attributed to implementation of the Dutch FH program. Results: In this model constructed to simulate the progression of FH in 1000 hypothetical 10-year-olds, from a health care perspective, the program would gain 2.53 QALYs per person, at an additional cost of €23 365 ($25 468) (both discounted). These equated to an ICER of €9220 ($10 050) per QALY gained. From the societal perspective, the detection and treatment program were cost saving over a lifetime compared with no cascade screening for FH. The ROI for the detection and treatment program for FH in children was €8.37 ($9.12). Conclusions and Relevance: The findings of this study suggest that the early detection and treatment program for FH in children may offer a good value for investment, being both health and cost saving. The findings and interpretations are conditional on assumptions inherent in the health economic model.

Lipoprotein(a) levels in children with homozygous familial hypercholesterolaemia: A cross-sectional study.

Homozygous familial hypercholesterolaemia (HoFH) is a life-threatening disorder characterized by extremely elevated low-density lipoprotein cholesterol (LDL-C) levels. Untreated, severe atherosclerotic cardiovascular disease (ASCVD), including aortic valve stenosis (AVS), may already occur in childhood. Another important genetic risk factor for ASCVD and AVS is elevated lipoprotein(a) [Lp(a)], which is highly prevalent in the general paediatric population. However, data on Lp(a) in children with HoFH are scarce. Therefore, we performed a cross-sectional study to evaluate Lp(a) levels in children with HoFH and compared them to children with heterozygous FH (HeFH) and unaffected children. Adjusted least-square mean (95% CI) Lp(a) levels in HoFH (n=29), HeFH (n=101) and unaffected children (n=102) were 18.7 (12.0-29.1), 15.3 (11.8-19.8) and 10.5 (8.3-13.2) mg/dL, respectively (p-for-trend=0.007). Lp(a) levels in children with HoFH were higher than in children with HeFH and in unaffected children. Given the very high ASCVD risk with HoFH, identifying other risk factors such as elevated Lp(a) in these children is important. Therefore, Lp(a) levels should be measured at least once in all children with HoFH.

How Genetic Variants in Children with Familial Hypercholesterolemia Not Only Guide Detection, but Also Treatment.

Familial hypercholesterolemia (FH) is a hereditary disorder that causes severely elevated low-density lipoprotein (LDL-C) levels, which leads to an increased risk for premature cardiovascular disease. A variety of genetic variants can cause FH, namely variants in the genes for the LDL receptor (LDLR), apolipoprotein B (APOB), proprotein convertase subtilisin/kexin type 9 (PCSK9), and/or LDL-receptor adaptor protein 1 (LDLRAP1). Variants can exist in a heterozygous form (HeFH) or the more severe homozygous form (HoFH). If affected individuals are diagnosed early (through screening), they benefit tremendously from early initiation of lipid-lowering therapy, such as statins, and cardiovascular imaging to detect possible atherosclerosis. Over the last years, due to intensive research on the genetic basis of LDL-C metabolism, novel, promising therapies have been developed to reduce LDL-C levels and subsequently reduce cardiovascular risk. Results from studies on therapies focused on inhibiting PCSK9, a protein responsible for degradation of the LDLR, are impressive. As the effect of PCSK9 inhibitors (PCSK9-i) is dependent of residual LDLR activity, this medication is less potent in patients without functional LDLR (e.g., null/null variant). Novel therapies that are expected to become available in the near future focused on inhibition of another major regulatory protein in lipid metabolism (angiopoietin-like 3 (ANGPTL3)) might dramatically reduce the frequency of apheresis in children with HoFH, independently of their residual LDLR. At present, another independent risk factor for premature cardiovascular disease, elevated levels of lipoprotein(a) (Lp(a)), cannot be effectively treated with medication. Further understanding of the genetic basis of Lp(a) metabolism, however, offers a possibility for the development of novel therapies.

Counseling couples at risk of having a child with homozygous familial hypercholesterolemia - Clinical experience and recommendations.

Homozygous familial hypercholesterolemia (HoFH) is a rare, potentially life-limiting, inherited disorder of lipoprotein metabolism characterized by extremely high low-density lipoprotein cholesterol levels. When both parents have heterozygous FH, there is a 25% chance they will conceive a child with HoFH. Here we describe our clinical experience with two such prospective parent couples who were counseled regarding reproductive options and prenatal testing for HoFH. These cases showcase how, in consultation with a molecular geneticist and pediatric cardiologist, parents may be informed of the prognosis and treatment outlook of HoFH based on the FH-variants carried, to ultimately make personal decisions on reproductive options. One couple opted for prenatal testing and termination of pregnancy in case HoFH was found, while the other accepted the risk without testing. We review the available literature on preconception counseling for HoFH and provide practical guidance to clinicians counseling at-risk couples. Optimal counseling of prospective parents may help prevent future physical and psychological problems for both parent and child.

Lipoprotein(a) levels in children with suspected familial hypercholesterolaemia: a cross-sectional study.

AIMS: Familial hypercholesterolaemia (FH) predisposes children to the early initiation of atherosclerosis and is preferably diagnosed by DNA analysis. Yet, in many children with a clinical presentation of FH, no mutation is found. Adult data show that high levels of lipoprotein(a) [Lp(a)] may underlie a clinical presentation of FH, as the cholesterol content of Lp(a) is included in conventional LDL cholesterol measurements. As this is limited to adult data, Lp(a) levels in children with and without (clinical) FH were evaluated. METHODS AND RESULTS: Children were eligible if they visited the paediatric lipid clinic (1989-2020) and if Lp(a) measurement and DNA analysis were performed. In total, 2721 children (mean age: 10.3 years) were included and divided into four groups: 1931 children with definite FH (mutation detected), 290 unaffected siblings/normolipidaemic controls (mutation excluded), 108 children with probable FH (clinical presentation, mutation not detected), and 392 children with probable non-FH (no clinical presentation, mutation not excluded). In children with probable FH, 32% were found to have high Lp(a) [geometric mean (95% confidence interval) of 15.9 (12.3-20.6) mg/dL] compared with 10 and 10% [geometric means (95% confidence interval) of 11.5 (10.9-12.1) mg/dL and 9.8 (8.4-11.3) mg/dL] in children with definite FH (P = 0.017) and unaffected siblings (P = 0.002), respectively. CONCLUSION: Lp(a) was significantly higher and more frequently elevated in children with probable FH compared with children with definite FH and unaffected siblings, suggesting that high Lp(a) may underlie the clinical presentation of FH when no FH-causing mutation is found. Performing both DNA analysis and measuring Lp(a) in all children suspected of FH is recommended to assess possible LDL cholesterol overestimation related to increased Lp(a).