Implications of cardiac risk and low-density lipoprotein cholesterol distributions in the United States for the diagnosis and treatment of dyslipidemia: data from National Health and Nutrition Examination Survey 1999 to 2002

Abstract

Background: Updated guidelines from the National Cholesterol Education Program Adult Treatment Panel III stratify patients into 5 groups of coronary heart disease (CHD) risk that determine intensity of lipid-lowering therapy. The present study assesses the distribution of low-density lipoprotein cholesterol (LDL-C) in the United States across the 5 groups of CHD risk as defined in the updated guidelines.

Methods and results: Subjects included 7399 individuals 20 to 79 years of age in the 1999 to 2002 National Health and Nutrition Examination Survey representing 171 million individuals in the United States. CHD risk, LDL-C levels, and goal achievement were determined per Adult Treatment Panel III guidelines. CHD risk assessment incorporated a medical condition review, risk factor summation, and Framingham Risk Score calculation. Percentages were weighted to represent population estimates, and SEs were adjusted for the survey design. The distribution of individuals by CHD risk included 61.1% at lower risk, 10.6% at high risk, and 5.7% at very high risk. From Adult Treatment Panel III criteria, only 5.4% of the population was at "intermediate" risk. Two thirds (66.3%) met their Adult Treatment Panel III-defined LDL-C goal. Of those at high and very high risk, 23% and 26%, respectively, met the goal of LDL-C <100 mg/dL, whereas only 3.1% and 4.6% had an LDL-C <70 mg/dL (or non-high-density lipoprotein C <100 mg/dL).

Conclusions: Most adult US residents are at lower 10-year CHD risk and meet risk-adjusted LDL-C goals. However, large portions of the high-risk population are undertreated. The commonly described population at intermediate risk is small. A novel method of identifying patients who might benefit from additional testing to determine their treatment strategy is provided.