Non-HDL Cholesterol Versus LDL Cholesterol as a CVD Risk Factor in Diabetic Subjects

Objective: Serum low density lipoprotein (LDL) cholesterol is considered as the primary target of lipid lowering therapy and non-high density lipoprotein (HDL) cholesterol is the recommended second target. Recent studies claimed that non-HDL cholesterol is a better predictor of cardiovascular diseases (CVD) than LDL cholesterol. In this study we aimed to compare non-HDL cholesterol and LDL cholesterol as a CVD risk factor in confirmed diabetic subjects. Materials and methods: In this cross-sectional observational study, 1042 confirmed diabetic subjects selected randomly were included. HbA1c concentrations were measured by modified high-performance liquid chromatography. Serum total cholesterol (TC) and triglycerides (TG) concentrations were measured by enzymatic end point method. Serum HDL cholesterol was measured by a direct automated method and LDL cholesterol was calculated by Friedewald’s formula. Subjects having TC d” 150 mg/dL and TG 400 mg/dL were excluded. Selected subjects were divided into 5 groups depending on TG values (up to TG concentrations of 150 mg/dL, 151-200 mg/dL, 201-250 mg/dL, 251-300 mg/dL and 301-400 mg/dL respectively). In each group, number of individuals with LDL cholesterol d” 100 mg/dL, non HDL cholesterol d”130 mg/dL and LDL cholesterol 100 mg/dL, non-HDL cholesterol 130 mg/dL were calculated and compared by Fisher’s exact test. Results: In the total subjects, 767 (74%) subjects had LDL cholesterol 100 mg/dL and 822 (79%) subjects had non- HDL cholesterol 130 mg/dL. HbA1c values were different (p 0.02) in five groups and showed upward trend (p 0.01). All the lipid parameters studied were significantly different in five groups (p 0.0001) and TC, TG and non-HDL cholesterol showed upward trend (p 0.0001), but HDL cholesterol and LDL cholesterol showed downward trend (p 0.0001). Odds ratio (OR) of likelihood of risk individuals regarding non-HDL cholesterol compared to LDL cholesterol were 0.50 (p 0.001), 1.32 (p 0.05), 2.96 (p 0.001), 6.49 (p 0.001) and 9.37 (p 0.001) for TG concentrations of up to 150 mg/dL, 151-200 mg/dL, 201-250 mg/dL, 251-300 mg/dL and 301-400 mg/dL respectively with relative risk of 0.60, 1.24, 2.43, 4.83, 5.10. Conclusion: LDL cholesterol is a better tool for the detection of high-risk individuals than non-HDL cholesterol at TG concentration up to 150 mg/dL, whereas non-HDL cholesterol is better than LDL cholesterol at TG concentration above 200 mg/dL as a CVD risk factor.