Clinicians receive conflicting advice on whether to order blood tests to screen for lipids in children. A new study could add to the confusion. Researchers found that a combination of physical proxy measures such as hypertension and body mass index (BMI) predicted the risk for future cardiovascular events as well as the physical model plus lipid labs, questioning the value of those blood tests.
Some medical organizations advise screening only for high-risk children because more research is needed to define the harms and benefits of universal screening. Diet and behavioral changes are sufficient for most children, and universal screening could lead to false positives and unnecessary further testing, they said.
Groups that favor lipid tests for all children say these measurements detect familial hypercholesterolemia (FH) that would not otherwise be diagnosed, leading to treatment with drugs like statins and a greater chance of preventing cardiovascular disease (CVD) in adulthood.
Researchers from the new study said their findings do not address screenings for FH, which affects 1 in 250 US children and puts them at a risk for atherosclerotic CVD.
Recommending Blood Tests in Age Groups
One of the seminal guidelines on screening lipids in children came from the National Heart, Lung, and Blood Institute (NHLBI), which in 2011 recommended children undergo dyslipidemia screening between the ages of 9 and 11 years and again between 17 and 21 years. Children should receive a screening starting at age 2 years if they have a family history of CVD or dyslipidemia or have diabetes, an elevated BMI, or hypertension. The American Academy of Pediatrics shortly followed suit, issuing similar recommendations.
Screening for the two subsets of ages was an expansion from the original 1992 guidelines from the National Cholesterol Education Program, which recommended screening only for children with either a family history of early CVD or elevated total cholesterol levels.
A 2011 panel for the NHLBI said the older approach identified significantly fewer children with abnormal levels of low-density lipoprotein cholesterol (LDL-C) than the addition of two age groups for screening, adding that many children do not have a complete family history. The American College of Cardiology and American Heart Association later supported NHLBI’s stance in their joint guidelines on the management of cholesterol.
Mark Corkins, MD, chair of the AAP’s Committee on Nutrition, told Medscape Medical News that if children are screened only because they have obesity or a family history of FH, some with elevated lipid levels will be missed. For instance, studies indicate caregiver recall of FH often is inaccurate, and the genetic disorder that causes the condition is not related to obesity.
“The screening is to find familial hypercholesterolemia, to try to find the ones that need therapy,” that would not be caught by the risk-based screening earlier on in childhood, Corkins said.
Only Screen Children With Risk Factors
But other groups do not agree. The US Preventive Services Task Force (USPSTF) found insufficient evidence to recommend for or against screening for lipid disorders in asymptomatic children and teens.