Data support targeted approach to cholesterol screening in young adults

The 10-year risk for atherosclerotic cardiovascular disease was less than one half of 1% in nonsmoking, nondiabetic women younger than age 50 years and men younger than age 40 years.

Healthy women under the age of 50 years and men under the age of 40 years who do not smoke and do not have hypertension are at low risk for atherosclerotic cardiovascular disease (ASCVD) and might not benefit from regular cholesterol screening, a study found.

The 2013 cholesterol management guidelines from the American College of Cardiology (ACC) and American Heart Association (AHA) recommend an initial lipid panel for all adults older than age 20 years, followed by repeat testing every four to six years to identify those at high risk for ASCVD. In contrast, the 2008 guideline from the U.S. Preventive Services Task Force (USPSTF) recommends that screening start at 35 years for men and 45 years for women unless at least one risk factor is present.

To compare the two approaches, researchers analyzed data from the National Health and Nutrition Examination Survey on adults ages 30 to 49 years without known ASCVD or diabetes. Results were published online May 16 by Annals of Internal Medicine.

Overall, 9,608 people were included. Almost half (47.12%) were low risk, that is, researchers calculated that the prevalence of elevated cardiovascular risk among them was no greater than 1%. The 10-year ASCVD risk was very low (less than one half of 1%) in nonsmoking, nondiabetic women younger than age 50 years and men younger than age 40 years. In the absence of smoking or hypertension, 0.09% (95% CI, 0.02% to 0.35%) of adult men younger than age 40 years and 0.04% (95% CI, 0.0% to 0.26%) of adult women younger than age 50 years had an elevated risk. Overall, 2.9% (95% CI, 2.3% to 3.5%) of the survey population had an LDL cholesterol (LDL-C) level of 190 mg/dL or greater.

Given the low prevalence of patients at elevated cardiovascular risk, the findings would support the more targeted approach of the USPSTF guidelines, the authors wrote.

The authors of an accompanying editorial disagreed. The data were cross-sectional and no actual clinical events were recorded, the editorial stated. The primary analysis excluded all persons younger than age 50 years who were receiving statins or who had already had a major vascular event. Yet these persons very likely had a strong family history or elevated cholesterol levels, and that bias might substantially alter the effective screening rates.

“Absence of evidence is not evidence of absence,” the editorial concluded. “We disagree with the USPSTF recommendation to delay lipid screening until mid-adulthood simply because clinical trial evidence is not available in younger persons. Rather, we believe that at least 1-time LDL-C screening should be universally recommended for all patients in their late teen or early adult years. If anything, we support the principled biologic approach promoted by the American Academy of Pediatrics, which recommends that all children be screened for high cholesterol levels at least once between the ages of 9 and 11 years, and again between ages 17 and 21 years.”