Joint distribution of non-HDL and LDL cholesterol and coronary heart disease risk prediction among individuals with and without diabetes.

OBJECTIVE: To assess coronary heart disease (CHD) risk within levels of the joint distribution of non-HDL and LDL cholesterol among individuals with and without diabetes. RESEARCH DESIGN AND METHODS: We used four publicly available data sets for this pooled post hoc analysis and confined the eligible subjects to white individuals aged > or = 30 years and free of CHD at baseline (12,660 men and 6,721 women). Diabetes status was defined as either "reported by physician-diagnosed and on medication" or having a fasting glucose level > or = 126 mg/dl at the baseline examination. The primary end point was CHD death. Within diabetes categories, risk was assessed based on lipid levels (in mg/dl): non-HDL <130 and LDL <100 (group 1); non-HDL <130 and LDL > or = 100 (group 2); non-HDL > or = 130 and LDL <100 (group 3); and non-HDL > or = 130 and LDL > or = 100 (group 4). Group 1 within those without diabetes was the overall reference group.
RESULTS: Of the subjects studied, approximately 6% of men and 4% of women were defined as having diabetes. A total of 773 CHD deaths occurred during the average 13 years of follow-up time. A Cox proportional hazard model was used to estimate the relative risk (RR) of CHD death. Those with diabetes had a 200% higher RR than those without diabetes. In a multivariate model, CHD risk in those with diabetes did not increase with increasing LDL, whereas it did increase with increasing non-HDL: RR (95% confidence interval) for group 1: 5.7 (2.0-16.8); group 2: 5.7 (1.6-20.7); group 3: 7.2 (2.6-19.8); and group 4: 7.1 (3.7-13.6).
CONCLUSIONS: Non-HDL is a stronger predictor of CHD death among those with diabetes than LDL and should be given more consideration in the clinical approach to risk reduction among diabetic patients.