The clinical and molecular diversity of homozygous familial hypercholesterolemia in children: Results from the GeneTics of clinical homozygous hypercholesterolemia (GoTCHA) study.

BACKGROUND: Homozygous familial hypercholesterolemia (hoFH) is either diagnosed on the identification of pathogenic genetic variants in LDLR, APOB, or PCSK9 or by phenotypic parameters of which an extremely elevated LDL-C level >13 mmol/L (>500 mg/dL) is the most prominent hallmark. Little is known about the clinical spectrum in children with hoFH. OBJECTIVE: We set out to investigate the phenotypical spectrum of genetically defined hoFH in our pediatric cohort and evaluated how many pediatric patients, now classified as heterozygous, carry a second mutation, which would reclassify these patients as hoFH. METHODS: We analyzed the data of a total of 1903 children with molecularly proven FH. Subsequently we performed candidate gene sequencing in the cohort of heterozygous familial hypercholesterolemia children in whom the LDL-C level was above the lowest level measured in the pediatric patients with hoFH. RESULTS: Of our 13 hoFH children, 8 (62%) had LDL-C levels below the clinical hoFH criteria of 13 mmol/L (500 mg/dL). In the remaining 1890 patients with heterozygous familial hypercholesterolemia, 64 (3.4%) had LDL-C levels equal to or above the lowest LDL-C level in a patient with hoFH carrying 2 deleterious variants (8.36 mmol/L or 323.3 mg/dL). No additional pathogenic variants in LDLR and APOB were identified. In 2 related patients, a PCSK9 gain of function mutation was found. CONCLUSION: We show that LDL-C levels vary among pediatric patients with molecularly proven hoFH, and that most of these patients do not meet the clinical LDL-C criteria for hoFH. The levels overlap with LDL-C levels in true heterozygous patients. This warrants a critical reappraisal of the current LDL-C cutoffs for the phenotypic diagnosis of hoFH in children.

Effect of Rosuvastatin on Carotid Intima-Media Thickness in Children With Heterozygous Familial Hypercholesterolemia: The CHARON Study (Hypercholesterolemia in Children and Adolescents Taking Rosuvastatin Open Label).

BACKGROUND: Heterozygous familial hypercholesterolemia (HeFH) is an autosomal dominant disorder leading to premature atherosclerosis. Children with HeFH exhibit early signs of atherosclerosis manifested by increased carotid intima-media thickness (IMT). In this study, we assessed the effect of 2-year treatment with rosuvastatin on carotid IMT in children with HeFH. METHODS: Children with HeFH (age, 6-<18 years) and low-density lipoprotein cholesterol >4.9 mmol/L or >4.1 mmol/L in combination with other risk factors received rosuvastatin for 2 years, starting at 5 mg once daily, with uptitration to 10 mg (age, 6-<10 years) or 20 mg (age, 10-<18 years). Carotid IMT was assessed by ultrasonography at baseline and 12 and 24 months in all patients and in age-matched unaffected siblings. Carotid IMT was measured at 3 locations (common carotid artery, carotid bulb, internal carotid artery) in both the left and right carotid arteries. A linear mixed-effects model was used to evaluate differences in carotid IMT between children with HeFH and the unaffected siblings. P values were adjusted for age, sex, carotid artery site, and family relations. RESULTS: At baseline, mean±SD carotid IMT was significantly greater for the 197 children with HeFH compared with the 65 unaffected siblings (0.397±0.049 and 0.377±0.045 mm, respectively; P=0.001). During 2 years of follow-up, the change in carotid IMT was 0.0054 mm/y (95% confidence interval, 0.0030-0.0082) in children with HeFH and 0.0143 mm/y (95% confidence interval, 0.0095-0.0192) in unaffected siblings (P=0.002). The end-of-study difference in mean carotid IMT between children with HeFH and unaffected siblings after 2 years was no longer significant (0.408±0.043 and 0.402±0.042 mm, respectively; P=0.2). CONCLUSIONS: In children with HeFH who were ≥6 years of age, carotid IMT was significantly greater at baseline compared with unaffected siblings. Rosuvastatin treatment for 2 years resulted in significantly less progression of increased carotid IMT in children with HeFH than untreated unaffected siblings. As a result, no difference in carotid IMT could be detected between the 2 groups after 2 years of rosuvastatin. These findings support the value of early initiation of statin treatment for low-density lipoprotein cholesterol reduction in children with HeFH. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01078675.

Population pharmacokinetics of rosuvastatin in pediatric patients with heterozygous familial hypercholesterolemia.

PURPOSE: Data from two clinical studies (hyperCholesterolaemia in cHildren and Adolescents taking Rosuvastatin OpeN label [CHARON; NCT01078675] and Study 4522IL/0086) were used to describe rosuvastatin pharmacokinetics in patients with heterozygous familial hypercholesterolemia aged ≥6 to <18 years. METHODS: Rosuvastatin concentration-time data were analyzed via non-linear mixed-effects modeling (NONMEM), with clearance (CL/F) as the pre-defined key pharmacokinetic parameter of interest. In addition, descriptive comparisons between pediatric patients and adults (healthy and dyslipidemic) were performed. The dataset included 214 pediatric patients, with 2,029 rosuvastatin concentrations. RESULTS: A linear two-compartment model with first-order absorption and elimination processes adequately described the combined dataset. Weight and gender were significant covariates for CL/F, with moderate between-patient variability remaining (coefficient of variation (CV) 40 %): CL/F in female children was approximately 30 % lower than in male children, and there was a twofold mean difference in CL/F across the observed weight range. Age was not a significant covariate after accounting for weight and gender differences. However, weight and gender only reduced between-patient variability from 45 (without covariates) to 40 % and are considered unlikely to be clinically relevant. CONCLUSIONS: Rosuvastatin pharmacokinetics appeared generally predictable with respect to dose, and time (study duration) and the exposure (dose-normalized area under the plasma concentration-time curve at steady state (AUCss)) in children and adolescents appeared to be similar or lower than adult patients with dyslipidemia.

Efficacy and safety of rosuvastatin therapy in children and adolescents with familial hypercholesterolemia: Results from the CHARON study.

OBJECTIVE: Heterozygous familial hypercholesterolemia (HeFH) is an autosomal dominant disorder leading to premature atherosclerosis. Guidelines recommend initiating statins early to reduce low-density lipoprotein cholesterol (LDL-C). Studies have evaluated rosuvastatin in children aged ≥10 years, but its efficacy and safety in younger children is unknown. METHODS: Children with HeFH and fasting LDL-C >4.92 mmol/L (190 mg/dL) or >4.10 mmol/L (>158 mg/dL) with other cardiovascular risk factors received rosuvastatin 5 mg daily. Based on LDL-C targets (<2.85 mmol/L [<110 mg/dL]), rosuvastatin could be uptitrated to 10 mg (aged 6-9 years) or 20 mg (aged 10-17 years). Treatment lasted 2 years. Changes in lipid values, growth, sexual maturation, and adverse events (AEs) were assessed. RESULTS: The intention-to-treat analysis included 197 patients. At 24 months, LDL-C was reduced by 43, 45, and 35% vs baseline in patients aged 6-9, 10-13, and 14-17 years, respectively (P < .001 for all groups). Most AEs were mild. Intermittent myalgia was reported in 11 (6%) patients and did not lead to discontinuation of rosuvastatin treatment. Serious AEs were reported by 9 (5%) patients, all considered unrelated to treatment by the investigators. No clinically important changes in hepatic biochemistry were reported. Rosuvastatin treatment did not appear to adversely affect height, weight, or sexual maturation. CONCLUSIONS: In HeFH patients aged 6-17 years, rosuvastatin 5-20 mg over 2 years significantly reduced LDL-C compared with baseline. Treatment was well tolerated, with no adverse effects on growth or sexual maturation.

Gonadal steroids, gonadotropins and DHEAS in young adults with familial hypercholesterolemia who had initiated statin therapy in childhood.

OBJECTIVE: Statins are currently the preferred pharmacological therapy in children with familial hypercholesterolemia (FH) with the aim to prevent premature cardiovascular disease (CVD). However, concerns have been raised that lowering cholesterol levels with statins could interfere with hormone production. In this study hormone concentrations were assessed in young adult FH subjects before and 10 years after the initiation of statins, and compared with their unaffected siblings. METHODS: All 214 FH children (8-18 years) who were previously randomized into a placebo-controlled trial evaluating the 2-year efficacy and safety of pravastatin, and their 95 unaffected siblings, were eligible. Women using oral contraceptives were excluded. Fasted blood samples were taken to measure lipids and testosterone (males), estradiol (females), luteinizing hormone (LH), follicle-stimulating hormone (FSH) and dehydroepiandosterone (DHEAS). RESULTS: After ten years, gonadal steroid and gonadotropin concentrations were within the reference interval and did not differ between FH subjects (n = 88) and unaffected siblings (n = 62). Mean DHEAS concentrations (±standard deviation) in the FH subjects and female siblings were normally distributed within the reference interval, whereas male siblings had a higher mean DHEAS concentration than their FH brothers (12.9 [± 4.9] vs. 8.4 [± 3.0] µmol/L, respectively, p < 0.0001). CONCLUSION: After ten years of statin treatment, testosterone, estradiol, LH and FSH concentrations in young adult FH patients are within the reference interval and comparable to their unaffected siblings. These results strengthen current guidelines that statins in FH subjects could be safely used from childhood onwards to prevent premature CVD.

Efficacy and Safety of Pitavastatin in Children and Adolescents at High Future Cardiovascular Risk.

OBJECTIVES: To assess the safety and efficacy of pitavastatin in children and adolescents with hyperlipidemia. STUDY DESIGN: A total of 106 children and adolescents with hyperlipidemia, ages 6 to 17 years, were enrolled in a 12-week randomized, double-blind, placebo-controlled study and randomly assigned to pitavastatin 1 mg, 2 mg, 4 mg, or placebo. During a 52-week extension period, subjects were up-titrated from 1 mg pitavastatin to a maximum dose of 4 mg in an effort to achieve an optimum low-density lipoprotein cholesterol (LDL-C) treatment target of <110 mg/dL (2.8 mmol/L). Adverse events rates, including abnormal clinical laboratory variables, vital signs, and physical examination were assessed. RESULTS: Compared with placebo, pitavastatin 1, 2, and 4 mg significantly reduced LDL-C from baseline by 23.5%, 30.1%, and 39.3%, respectively, and in the open-label study 20.5% of the subjects reached the LDL-C goal <110 mg/dL (2.8 mmol/L). No safety issues were evident. CONCLUSIONS: Pitavastatin at doses up to 4 mg is well tolerated and efficacious in children and adolescents aged 6-17 years. TRIAL REGISTRATION: Registered with EudraCT 2011-004964-32 and EudraCT 2011-004983-32.

Early initiation of statin treatment in children with familial hypercholesterolaemia.

PURPOSE OF REVIEW: This article provides recent insights on the early onset of atherosclerosis in heterozygous familial hypercholesterolemia and reports on novel treatment options as well as on the consequences of long-term statin use in childhood. RECENT FINDINGS: Children with familial hypercholesterolemia have greater mean carotid intima-media thickness (cIMT) than their unaffected siblings even before the age of 8 years, which is several years earlier than previously reported. In those children, 2 years of rosuvastatin treatment resulted in slowing of the cIMT progression. In addition, in a 10-year follow-up study after a pravastatin intervention trial, long-term statin therapy in young adult familial hypercholesterolemia patients was associated with normalization of cIMT progression and appeared effective in prevention of very premature cardiovascular events. These effects were observed without untoward safety concerns. However, a majority of these young adults did not reach cholesterol goals according to general guidelines, indicating the need for improvement of treatment in this patient group. SUMMARY: The importance, efficacy and safety of early initiation statin therapy in familial hypercholesterolemia children were further confirmed by recent findings. Nevertheless, to reach current treatment goals, the use of more potent statins is required and has been proven well tolerated and effective in young children.

Long-term statin treatment in children with familial hypercholesterolemia: more insight into tolerability and adherence.

BACKGROUND: Statins are currently the preferred pharmacological therapy in individuals with familial hypercholesterolemia (FH) with the aim to prevent premature atherosclerosis. In adults, these agents have been proven to be safe and well tolerated; however, non-adherence is a significant clinical issue. OBJECTIVES: In this study, we evaluated tolerability and adherence to statin therapy in young adult FH patients 10 years after this was initiated in their childhood. METHODS: A questionnaire including items on medical history, adherence and reasons for discontinuation was sent to 214 young adult FH patients that initiated statin therapy at least 10 years ago. Tolerability was defined as 100% minus the percentage of patients that discontinued statin therapy due to side effects. Adherence was defined as the extent to which patients took their medication as prescribed by their physician. We labelled patients adherent if they took 80% or more of their pills in the month preceding our assessment. RESULTS: Follow-up was successful in 205 (95.8%) subjects (age 18-30 years). A history of side effects was reported by 40 (19.5%) of the patients, and mainly consisted of muscle complaints and gastrointestinal symptoms. Three patients (1.5%) discontinued statin therapy because of side effects. Rhadbomyolysis or other serious adverse events were not reported. In fact, 169 (82.4%) of 205 patients remained on statin treatment and 78.7% (148 out of 188) were adherent. None of the patient characteristics were significantly associated with adherence. CONCLUSIONS: Individuals with FH who started statin therapy in childhood demonstrated good adherence during ten years of treatment. Furthermore, statin therapy was well tolerated; only a small minority discontinued therapy because of side effects and the side effects that were reported were mild in nature.

Management of hypercholesterolemia in children.

Cardiovascular disease (CVD) remains the leading cause of death and morbidity in our society. One of the major risk factors for CVD is hypercholesterolemia. Hypercholesterolemia in children can be caused by a hereditary disorder or can be secondary to other diseases or drugs. In order to prevent CVD later in life, children with hypercholesterolemia should be identified and treated as early as possible. Currently, several different screening strategies have been developed, using either universal screening or case finding to search for children at risk. Once those children are identified, the first step in treatment is lifestyle adjustment. If cholesterol levels remain elevated, the drugs of first choice are statins. Other pharmacological options are ezetimibe or bile acid sequestrants. These agents have all proven to be safe and effective in lowering low-density lipoprotein cholesterol levels and improving surrogate markers of CVD. However, there is a need for long-term follow-up studies to answer the question as to whether it is safe to initiate treatment at a young age to prevent CVD later in life.

Statin therapy and secretory phospholipase A2 in children with heterozygous familial hypercholesterolemia.

OBJECTIVE: Secretory phospholipase A2 (sPLA2) enzymes are thought to contribute to atherosclerosis. In this study we assessed levels of sPLA2 mass and activity, and their relationship to baseline characteristics of children with familial hypercholesterolemia (FH). Furthermore, we evaluated the effect of two years of pravastatin therapy on sPLA2 levels. METHODS AND RESULTS: sPLA2-IIA mass and sPLA2 activity were measured at baseline and after two years in 187 children with FH (aged 8-18 years) randomized to pravastatin or placebo. At baseline, median [IQR] sPLA2-IIA mass and sPLA2 activity levels were 7.2 [5.8-13.2] ng/ml and 36.4 [29.8-47.1] U/ml, respectively. Both sPLA2-IIA mass and sPLA2 activity were significantly correlated with high-sensitivity C-reactive protein (r = 0.33, p < 0.001 and r = 0.386, p < 0 .001, respectively), but not with other cardiovascular risk factors. Baseline levels of sPLA2-IIA mass and sPLA2 activity were not significantly associated with carotid intima-media thickness (cIMT) at baseline or at the end of follow-up. After two years, sPLA2-IIA mass and sPLA2 activity levels were not significantly reduced in the pravastatin group (p = 0.20 and p = 0.63, respectively), nor in the placebo group (p = 0.17 and p = 0.11, respectively). Changes from baseline did not differ between the treatment groups for sPLA2-IIA mass (p = 0.48) and sPLA2 activity (p = 0.88). CONCLUSIONS: sPLA2-IIA mass and sPLA2 activity were not significantly associated with cIMT in our pediatric FH cohort. This could indicate that the potential predictive role of sPLA2 as a biomarker of cardiovascular disease in children with FH is limited. Treatment with pravastatin did not reduce sPLA2-IIA mass or sPLA2 activity levels, as compared to placebo. Further studies with larger samples are required to address these issues.

Drug therapy of hypercholesterolaemia in children and adolescents.

Cardiovascular disease (CVD) remains the leading cause of death and morbidity in the world. The origins of atherosclerosis and subsequent CVD begin in childhood. In order to prevent CVD, children and adolescents at high risk for premature atherosclerosis should be identified and treated as early as possible. Hypercholesterolaemia is a major risk factor for atherosclerosis. Childhood hypercholesterolaemia can be either primary, due to hereditary disorders such as familial hypercholesterolaemia (FH) and familial combined hyperlipidaemia (FCHL), or secondary due to obesity, diabetes mellitus or nephrotic syndrome. Current guidelines suggest screening for hypercholesterolaemia between the ages of 2 and 10 years. Treatment strategies include lifestyle interventions involving dietary changes and increased physical activity. If these interventions are insufficient in lowering serum low-density lipoprotein cholesterol (LDL-C) levels, pharmacological therapy should be considered from the age of 8 years. Currently, statins are the preferred initial pharmacological therapy and have proven to be both efficient and well tolerated. However, long-term data on safety, and regular monitoring of those patients treated with statins, are still required, because in children with primary hypercholesterolaemia, treatment should be continued for life.

Clinical practice. Protein-losing enteropathy in children.

Protein-losing enteropathy (PLE) is a rare complication of a variety of intestinal disorders characterized by an excessive loss of proteins into the gastrointestinal tract due to impaired integrity of the mucosa. The clinical presentation of patients with PLE is highly variable, depending upon the underlying cause, but mainly consists of edema due to hypoproteinemia. While considering PLE, other causes of hypoproteinemia such as malnutrition, impaired synthesis, or protein loss through other organs like the kidney, liver, or skin, have to be excluded. The disorders causing PLE can be divided into those due to protein loss from intestinal lymphatics, like primary intestinal lymphangiectasia or congenital heart disease and those with protein loss due to an inflamed or abnormal mucosal surface. The diagnosis is confirmed by increased fecal concentrations of alpha-1-antitrypsin. After PLE is diagnosed, the underlying cause should be identified by stool cultures, serologic evaluation, cardiac screening, or radiographic imaging. Treatment of PLE consists of nutrition state maintenance by using a high protein diet with supplement of fat-soluble vitamins. In patients with lymphangiectasia, a low fat with medium chain triglycerides (MCT) diet should be prescribed. Besides dietary adjustments, appropriate treatment for the underlying etiology is necessary and supportive care to avoid complications of edema. PLE is a rare complication of various diseases, mostly gastrointestinal or cardiac conditions that result into loss of proteins in the gastrointestinal tract. Prognosis depends upon the severity and treatment options of the underlying disease.