Prevalence of Elevated Cardiovascular Risks in Young Adults: A Cross-sectional Analysis of National Health and Nutrition Examination Surveys

Background: The 2013 cholesterol management guidelines from the American College of Cardiology and American Heart Association (ACC/AHA) recommend lipid screening in all adults older than 20 years to identify those at increased risk for atherosclerotic cardiovascular disease (ASCVD). Statins may be considered for patients with elevated 10-year risk (>5%) or a low-density lipoprotein cholesterol (LDL-C) level of 4.92 mmol/L (190 mg/dL) or greater. Objective: To describe the prevalence of elevated ASCVD risk among nondiabetic adults younger than 50 years. Design: Cross-sectional. Setting: NHANES (National Health and Nutrition Examination Survey), 1999 to 2000 through 2011 to 2012. Participants: Adults aged 30 to 49 years without known ASCVD or diabetes. Measurements: 10-year ASCVD risk was estimated by using the 2013 ACC/AHA ASCVD risk calculator. Participants were subdivided by age, sex, and history of smoking and hypertension. The percentages of adults in each subgroup with a 10-year ASCVD risk greater than 5% and of those with an LDL-C level of 4.92 mmol/L (190 mg/dL) or greater were estimated. Low-prevalence subgroups were defined as those in which a greater than 1% prevalence of elevated cardiovascular risk could be ruled out (that is, the upper 95% confidence bound for prevalence was <= 1%). Results: Overall, 9608 NHANES participants representing 67.9 million adults were included, with approximately half (47.12%, representing 32 million adults) in low-prevalence subgroups. In the absence of smoking or hypertension, 0.09% (95% CI, 0.02% to 0.35%) of adult men younger than 40 years and 0.04% (CI, 0.0% to 0.26%) of adult women younger than 50 years had an elevated risk. Among other subgroups, 0% to 75.9% of participants had an increased risk. Overall, 2.9% (CI, 2.3% to 3.5%) had an LDL-C level of 4.92 mmol/L (190 mg/dL) or greater. Limitation: No information was available regarding cardiovascular outcomes. Conclusion: In the absence of risk factors, the prevalence of increased ASCVD risk is low among women younger than 50 and men younger than 40 years.