A cholesterol-lowering diet does not produce adverse psychological effects in children: three-year results from the dietary intervention study in children

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.

Health effects of saturated and trans-fatty acid intake in children and adolescents: Systematic review and meta-analysis

BACKGROUND

Elevated cholesterol has been linked to cardiovascular disease in adults and preclinical markers of atherosclerosis in children, thus reducing saturated (SFA) and trans-fatty acids (TFA) intake from an early age may help to reduce cholesterol and the risk of cardiovascular disease later in life. The aim of this review is to examine the evidence for health effects associated with reducing SFA and TFA intake in free-living children, adolescents and young adults between 2 to 19 years of age.

DESIGN

Systematic review and meta-analysis of randomised controlled trials (RCTs) and prospective cohort studies. Study selection, assessment, validity, data extraction, and analysis were undertaken as specified by the Cochrane Collaboration and the GRADE working group. Data were pooled using inverse variance models with random effects.

DATA SOURCES

EMBASE; PubMed; Cochrane Central Register of Controlled Trials; LILACS; and WHO Clinical Trial Registry (up to July 2016).

ELIGIBILITY CRITERIA FOR SELECTING TRIALS

RCTs involving dietary interventions aiming to reduce SFA or TFA intakes and a control group, and cohort studies reporting the effects of SFA or TFA exposures, on outcomes including blood lipids; measures of growth; blood pressure; insulin resistance; and potential adverse effects. Minimum duration was 13 days for RCTs and one year for cohort studies. Trials of weight loss or confounded by additional medical or lifestyle interventions were excluded.

RESULTS

Compared with control diets, there was a highly statistically significant effect of reduced SFA intake on total cholesterol (mean difference (MD) -0.16 mmol/l, [95% confidence interval (CI): -0.25 to -0.07]), LDL cholesterol (MD -0.13 mmol/l [95% CI:-0.22 to -0.03]) and diastolic blood pressure (MD -1.45 mmol/l [95% CI:-2.34 to -0.56]). There were no significant effects on any other risk factors and no evidence of adverse effects.

CONCLUSIONS

Advice to reduce saturated fatty acids intake of children results in a significant reduction in total and LDL-cholesterol levels as well as diastolic blood pressure without evidence of adverse effects on growth and development. Dietary guidelines for children and adolescents should continue to recommend diets low in saturated fat.

Universal screening of cholesterol in children

Atherosclerosis begins in childhood, and these early lesions are related to cardiovascular risk factors, including non-high-density lipoprotein cholesterol (HDL-C). Genetic disorders of lipid metabolism, principally familial hypercholesterolemia, have a high frequency in the population (about 1:300-1:500), and cause cardiovascular morbidity beginning in the third decade of life. The current obesity epidemic in children has worsened cardiovascular risk status. Cardiovascular risk factors present in youth often track into adulthood and are more predictive of future subclinical atherosclerosis than risk factors measured in young adulthood. Further, modification of risk factors beginning in childhood and young adulthood can lead to restoration to normal or improvement in measures of subclinical atherosclerosis measures both in those with genetic dyslipidemias and those with dyslipidemia secondary to obesity. Prior recommended selective lipid screening strategies based on family history or presence of other cardiovascular risk factors have failed to capture many with genetic dyslipidemia. Medium-term clinical trials of statin therapy for inherited dyslipidemias are safe and effective in lowering low-density lipoprotein cholesterol (LDL-C). Cholesterol screening in childhood is necessary to prevent cardiovascular morbidity in those with genetic dyslipidemias and to increase awareness of the need for behavioral intervention in those with multiple cardiovascular risk factors, often a result of the obesity epidemic.

Screening and treatment for lipid disorders in children and adolescents: systematic evidence review for the US Preventive Services Task Force

OBJECTIVE

This was a systematic evidence review for the US Preventive Services Task Force, intended to synthesize the published evidence regarding the effectiveness of selecting, testing, and managing children and adolescents with dyslipidemia in the course of routine primary care.

METHODS

Literature searches were performed to identify published articles that addressed 10 key questions. The review focused on screening relevant to primary care of children without previously identified dyslipidemias, but included treatment trials of children with dyslipidemia because some drugs have only been tested in that population.

RESULTS

Normal values for lipids for children and adolescents are defined according to population levels (percentiles). Age, gender, and racial differences and temporal trends may alter these statistical cut points. Approximately 40% to 55% of children with elevated total cholesterol and low-density lipoprotein levels will continue to have elevated lipid levels on follow-up. Current screening recommendations based on family history will fail to detect substantial numbers (30%-60%) of children with elevated lipid levels. Drug treatment for dyslipidemia in children has been studied and shown to be effective only for suspected or proven familial monogenic dyslipidemias. Intensive dietary counseling and follow-up can result in improvements in lipid levels, but these results have not been sustained after the cessation of the intervention. The few trials of exercise are of fair-to-poor quality and show little or no improvements in lipid levels for children without monogenic dyslipidemias. Although reported adverse effects were not serious, studies were generally small and not of sufficient duration to determine long-term effects of either short or extended use.

CONCLUSIONS

Several key issues about screening and treatment of dyslipidemia in children and adolescents could not be addressed because of lack of studies, including effectiveness of screening on adult coronary heart disease or lipid outcomes, optimal ages and intervals for screening children, or effects of treatment of childhood lipid levels on adult coronary heart disease outcomes.

A summary of results of the Dietary Intervention Study in Children (DISC): lessons learned

Prevention of cardiovascular disease must begin in childhood, preferably before risk factors develop. Elevated low-density lipoprotein cholesterol levels in children are likely to track over time and become high-risk levels in adults. The Dietary Intervention Study in Children (DISC) was a multicenter, collaborative randomized trial in pre-adolescent children designed to test the efficacy and safety of a dietary intervention to lower saturated fat and cholesterol intake among growing children with elevated low-density lipoprotein cholesterol. Numerous DISC results, which include findings on lipids-lipoproteins, genetics, and nutrient adequacy, as well as descriptions of the behavioral intervention strategies, have been reported. A summary of practical findings and their potential clinical applications have not previously been published. Highlights of key lessons learned from DISC and translational applications of potential interest to nurses and other health care providers are presented.

Dietary recommendations to prevent and manage chronic pediatric health conditions: adherence, intervention, and future directions

This review provides a summary of the dietary aspects of pediatric health conditions. Within each condition, dietary recommendations are reviewed, and adherence rates, factors affecting adherence, and known interventions are reported. Findings indicate that knowledge is necessary but not sufficient for dietary change. Interventions specifically targeting diet appear more promising than interventions aimed at global treatment adherence. Behavioral interventions and group treatment modalities also appear promising. Recommendations for future research include a systematic assessment of barriers to dietary adherence across populations, integration of the research on normative development of eating behavior in childhood, and the application of this information to the design and implementation of future treatment.

Long-term safety and efficacy of a cholesterol-lowering diet in children with elevated low-density lipoprotein cholesterol: seven-year results of the Dietary Intervention Study in Children (DISC)

OBJECTIVE

Diets reduced in fat and cholesterol are recommended for children over 2 years of age, yet long-term safety and efficacy are unknown. This study tests the long-term efficacy and safety of a cholesterol-lowering dietary intervention in children.

METHODS

Six hundred sixty-three children 8 to 10 years of age with elevated low-density lipoprotein cholesterol (LDL-C) were randomized to a dietary intervention or usual care group, with a mean of 7.4 years' follow-up. The dietary behavioral intervention promoted adherence to a diet with 28% of energy from total fat, <8% from saturated fat, up to 9% from polyunsaturated fat, and <75 mg/1000 kcal cholesterol per day. Serum LDL-C, height, and serum ferritin were primary efficacy and safety outcomes.

RESULTS

Reductions in dietary total fat, saturated fat, and cholesterol were greater in the intervention than in the usual care group throughout the intervention period. At 1 year, 3 years, and at the last visit, the intervention compared with the usual care group had 4.8 mg/dL (.13 mmol/L), 3.3 mg/dL (.09 mmol/L), and 2.0 mg/dL (.05 mmol/L) lower LDL-C, respectively. There were no differences at any data collection point in height or serum ferritin or any differences in an adverse direction in red blood cell folate, serum retinol and zinc, sexual maturation, or body mass index.

CONCLUSION

Dietary fat modification can be achieved and safely sustained in actively growing children with elevated LDL-C, and elevated LDL-C levels can be improved significantly up to 3 years. Changes in the usual care group's diet suggest that pediatric practices and societal and environmental forces are having positive public health effects on dietary behavior during adolescence.

Management of hyperlipidemia in children

Atherosclerosis is a major cause of death and disability in adults. Recent investigations suggest that although cardiac end-points such as myocardial infarction and strokes mainly occur in middle-age and older subjects, the pathological basis for atherosclerosis begins in childhood. Hypercholesterolemia is one of the most important risk factors for atherosclerosis in adults and elevated cholesterol in children is associated with sub-clinical deposition of lipids in the aorta and coronary arteries. This report summarizes an approach to the diagnosis and treatment of hyperlipidemia in children. Based on guidelines from the National Cholesterol Education Program, children over 2 years of age should be screened for hypercholesterolemia if there is a family history of premature heart disease or hyperlipidemia. Therapy must be individualized. The majority of children with hyperlipidemia should be managed with a low-saturated fat and low-cholesterol diet. Children over 10 years of age with severe elevations of LDL-cholesterol and who come from high-risk families may be considered for more aggressive dietary therapy or medication in some cases. This is especially true for children with inherited disorders of lipid metabolism such as LDL-receptor deficiency. By identifying high-risk children and instituting therapy during childhood it is hoped that premature onset of adult coronary heart disease can be delayed or avoided altogether.