Management of hyperlipidemia in the pediatric population

Hyperlipidemia

Cardiovascular disease remains the top cause of morbidity and mortality in the United States. Atherosclerotic plaques are known to start in adolescence, and, therefore, young adults can be affected by coronary artery disease. Children with known risk factors, such as genetic predisposition, including familial hyperlipidemias, diabetes, and renal diseases, are at higher risk. With childhood obesity becoming an epidemic in certain parts of the United States, this problem is further highlighted as an important issue affecting children's health. There are unclear recommendations for pediatricians regarding cholesterol screening of pediatric populations, when to initiate hyperlipidemia treatment with statin therapy, and when to refer to a specialist for further management. This article reviews the epidemiology and pathophysiology of hyperlipidemia, recommendations for screening and types of screening, management (including pharmacology), prognosis, and prevention.

Familial hypertriglyceridemia

Familial hypertriglyceridemia (FHTG) is an uncommon primary (genetic) dyslipidemia. FHTG is characterized by moderately elevated serum triglycerides, usually in the absence of significant hypercholesterolemia and rarely manifests in childhood. We report an eight-month-old boy incidentally diagnosed as a case of FHTG due to lipemic serum (patient was admitted for malaria with anemia). He had elevated serum triglycerides with normal serum cholesterol, but had no symptoms related to the primary disorder (FHTG).

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

OBJECTIVE

Functional and morphological changes of the arterial wall already present in young children with heterozygous familial hypercholesterolemia (HeFH) suggest that treatment should be initiated early in life to prevent premature atherosclerotic cardiovascular disease. The purpose of this study was to assess the efficacy and particularly safety of statin therapy in children with HeFH.

METHODS AND RESULTS

We performed a meta-analysis of randomized, double-blind, placebo-controlled trials evaluating statin therapy in children aged 8 to 18 years with HeFH. Six studies (n=798 children) with 12 to 104 weeks of treatment were included. Total cholesterol, LDL cholesterol, and apolipoprotein B were significantly reduced, whereas HDL cholesterol and apolipoprotein A1 were significantly increased by statin therapy. No statistically significant differences were found between statin- and placebo-treated children with respect to the occurrence of adverse events (RR 0.99; 95% CI: 0.79 to 1.25), sexual development (RR of advancing > or = 1 stage in Tanner classification 0.96; 95% CI: 0.79 to 1.17), muscle toxicity (RR of CK > or = 10 times the upper limit of normal [ULN] 1.38; 95% CI: 0.18 to 10.82), or liver toxicity (RR of > or = 3 times the ULN for ASAT 0.98; 95% CI: 0.23 to 4.26 and for ALAT 2.03; 95% CI: 0.24 to 16.95). We found a minimal difference in growth in favor of the statin group (0.33 cm; 95% CI: 0.03 cm to 0.63 cm).

CONCLUSION

In addition to the fact that statin treatment is efficacious, our results support the notion that statin treatment in children with HeFH is safe. Thus, even though further studies are required to assess lifelong safety, statin treatment should be considered for all children aged 8 to 18 with HeFH.

Efficacy and safety of fluvastatin in children and adolescents with heterozygous familial hypercholesterolaemia

AIM

To assess whether early initiation of statin therapy for heterozygous familial hypercholesterolaemia favourably affects lipid profiles or vascular morphological changes.

METHODS

Children and adolescents aged 10-16 y with heterozygous familial hypercholesterolaemia were administered fluvastatin (80 mg/d) for 2 y in a single-arm two-centre study. Carotid B-mode intima-media thickness (IMT) and M-mode arterial wall stiffness (beta) were recorded. Eighty of the 85 enrolled subjects completed the trial.

RESULTS

The median decrease in low-density lipoprotein (LDL) cholesterol from baseline at last study visit was 33.9%; median decreases in total cholesterol, triglycerides and apolipoprotein B were 27.1%, 5.3% and 24.2%, respectively; the median increase in high-density lipoprotein (HDL) cholesterol was 5.3%. Changes in carotid arterial wall thickness and stiffness versus baseline were fractional and statistically non-significant (delta IMT -0.005 mm, 95% CI -0.018 to +0.007 mm, n=83; and delta beta = 0.017, 95% CI -0.219 to +0.253, n=79). Adverse events, all non-serious, were reported by 58 subjects (68.2%); four were suspected to be drug-related. Change in hormone levels and sexual maturation were appropriate for this age group.

CONCLUSION

Fluvastatin lowered LDL cholesterol, total cholesterol and apolipoprotein B levels effectively over a prolonged period in children and adolescents with heterozygous familial hypercholesterolaemia. Carotid IMT and wall stiffness remained largely unchanged.

Metabolic syndrome in children and adolescents

Metabolic syndrome is a constellation of interrelated risk factors of metabolic origin that often accompany obesity and consist of atherogenic dyslipidemia, elevated blood pressure, impaired glucose tolerance, a prothrombotic state, and a proinflammatory state. Using a modification of the criteria by the National Cholesterol Education Program Adult Treatment Panel III, metabolic syndrome in children and adolescents can be clinically diagnosed when three or more of the following are present: body mass index > or = 2 z score, systolic or diastolic blood pressure greater than 95th percentile, triglyceride level greater than 95th percentile, and/or high-density lipoprotein cholesterol less than 5th percentile and impaired glucose tolerance (fasting glucose > 110 mg/dL ). The prevalence of the metabolic syndrome in adolescents has been shown to be 4% overall, but it is 30% to 50% in overweight adolescents. In the United States, 18% to 22% of children and adolescents are overweight; the prevalence of a metabolic syndrome phenotype among US adolescents has also been increasing significantly over the past decade. All of the features of metabolic syndrome are risk factors for atherosclerosis, and metabolic syndrome has been shown to constitute risk for atherosclerotic cardiovascular disease in adults. In children and adolescents with metabolic syndrome, biomarkers of an increased risk of adverse cardiovascular outcomes are already present. Therefore, there is need for prevention and treatment of metabolic syndrome in this population. The mainstay of the treatment is dietary intervention and promotion of active lifestyle to achieve and maintain optimum weight, normal blood pressure, and normal lipid profile for the height and age. The pharmaceutical intervention is usually not required and its long-term outcome has not been studied. There is need for large studies for the management and long-term outcomes of metabolic syndrome in children and adolescents if the future tides of cardiovascular and other associated complications of metabolic syndrome are to be turned around.