Point: The rationale for universal lipid screening and treatment 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.

Identification of Factors Influencing Cholesterol Changes in Elementary-School Children: A Longitudinal Study

Changes in serum cholesterol levels during childhood may affect the risk of cardiovascular disease in adulthood. However, cholesterol level changes in Japanese children and adolescents and the factors that influence them have not been completely elucidated. This study aimed to determine whether cholesterol levels changed due to the effects of growth and identify factors. This cohort study included elementary-school children in the fourth grade (9−10-year-old) who underwent assessments of cholesterol levels and demographic and lifestyle characteristics. The participants were followed up in their first year of junior high school with the same laboratory, demographic, and lifestyle assessments. From the fourth year of elementary school to the first year of junior high school, children’s cholesterol levels decreased (p < 0.0001). Regarding bowel movements, cholesterol level reduction was significant in individuals with regular bowel movements but not significant in those with infrequent bowel movements. Weight was the factor that most strongly negatively predicted cholesterol level reduction (p < 0.001). The study demonstrated the significance of lifestyle factors for growth-related changes of total cholesterol levels and identified weight as the factor that most strongly influenced total cholesterol level changes. Guidance regarding lifestyle improvements should be imparted to children from the fourth grade of elementary school.

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.

Universal Lipid Screening in 9- to 11-Year-Olds Before and After 2011 Guidelines

OBJECTIVE

To determine whether the 2011 guidelines for universal routine screening for dyslipidemia in children aged 9 to 11 years, published by the Expert Panel on Integrated Guidelines for Cardiovascular Health and Risk Reduction in Children and Adolescents and National Heart, Lung, and Blood Institute, are being followed by pediatric primary-care providers.

METHODS

Retrospective data were obtained for 63,951 well-child visits (WCV) in children aged 9 to 11 years from 2 health care systems and 1 insurance program from 2009 to 2015. The proportion of WCV that had a lipid panel or total cholesterol test performed within 1 year of the visit was compared for 2009-2011 versus 2013-2015. Associations between demographic variables and lipid screening were evaluated with logistic regression. The frequency of tested children who had abnormal lipid results was evaluated.

RESULTS

Only 3.5% of 9- to 11-year WCV had lipid tests performed in association with the visit before and after the guidelines. Of those tested, 43% had an abnormal lipid result.

CONCLUSIONS

Utah clinicians rarely follow guidelines for universal lipid screening of children aged 9 to 11. This represents a missed opportunity to identify children at risk for early-onset cardiovascular disease.

Dyslipidemia Screening of 9- to 11-Year-Olds at Well-Child Visits by Utah Pediatricians

In 2011, an expert National Institutes of Health panel published the "Integrated Guidelines for CV Health and Risk Reduction in Children and Adolescents," which recommended screening all children aged 9 to 11 years for dyslipidemia. It is unknown if this guideline is being followed. We surveyed members of the Utah chapter of the American Academy of Pediatrics to determine whether they performed universal lipid screening at well-child visits (WCV) on their patients at 9,10, or 11 years and how comfortable they were with evaluating and/or managing children with dyslipidemia. Of the 118 respondents who practiced primary care, only 18 (15%) screened all children at WCV; 86 (73%) tested "some," most commonly children who were obese or had a positive family history. 18% were unfamiliar with the guidelines; 28% were familiar with the guidelines but felt they were "inappropriate;" 98 (84%) of the respondents said they were "very or somewhat comfortable" evaluating children with dyslipidemia.

The triglyceride-to-high density lipoprotein cholesterol ratio in overweight Korean children and adolescents

PURPOSE

The triglyceride-to-high-density lipoprotein cholesterol (TG/HDL-C) ratio has recently been reported as a biomarker of cardiometabolic risk in obese children and adolescents. The purpose of this study is to describe the TG/HDL-C ratio and related factors in overweight and normal weight Korean children and to evaluate whether the high TG/HDL-C ratio is associated with insulin resistance in overweight children and adolescents.

METHODS

Data from 255 overweight (aged 8.7±2.0 years) and 514 normal weight (aged 8.9±1.8 years) children and adolescents were evaluated. Glucose, insulin, total cholesterol (TC), HDL-C and TG levels were measured after overnight fasting, and the TG/HDL-C ratio, non-HDL-C and the homeostasis model assessment of insulin resistance (HOMA-IR) were calculated.

RESULTS

The TG/HDL-C ratio was higher in overweight group compared to normal weight group (P<0.001). Among overweight children and adolescents, alanine aminotransferase (P=0.018), non-HDL-C (P<0.001), and HOMA-IR (P=0.004) were different between the TG/HDL-C ratio tertile groups. The prevalence of elevated HOMA-IR was increased with increasing TG/HDL-C ratio tertiles (P for trend=0.003). On regression analysis adjusted for age and sex, the BMI (β=0.402, P=0.001) and TG/HDL-C ratio (β=0.251, P=0.014) were independently associated with HOMA-IR (adjusted R2=0.324). The TG/HDL-C ratio of 2.0 or more showed higher sensitivity (55.6%) and specificity (72.9%), when compared to TC (≥200 mg/dL), non-HDL-C (≥145 mg/dL), and LDL-C (≥130 mg/dL) for identifying overweight children with elevated HOMA-IR.

CONCLUSIONS

The TG/HDL-C ratio is independently associated with insulin resistance in overweight children and adolescents, and it can be useful in identifying those at higher cardiometabolic risk.