Background and Aim: Coronary artery disease (CAD) is the leading cause of death among diabetic patients. One of the risk factors for CAD is dyslipidemia. In regard to high prevalence of diabetes mellitus and CAD, we evaluated levels of serum lipid and lipoproteins in diabetic and nondiabetic patients with CAD.

Materials and Methods: In this case-control study, we compared serum lipid and lipoprotein of 100 patients with CAD and diabetes mellitus (case) with 100 patients with CAD without diabetes mellitus (control). Determination of serum lipids was performed on the first day of admission, following a 10 hour fasting. Data were analysed by SPSS and t-test at α=0.05.

Results: Mean cholesterol (Chol) and triglyceride (TG) of patients with CAD and diabetes mellitus (the case) was significantly higher than patients with CAD without diabetes (the control). But the mean HDL and LDL did not represent a significant difference between the two groups. Prevalence of hypercholestrolemia (Chol>200 mg/dl), hypertriglyceridemia (TG>200 mg/dl) and low HDL (HDL<35 mg/dl) in the case group was higher than those in the control group. LDL was higher in the control group.

Conclusion: Because of high prevalence of dyslipidemia in diabetic patients with CAD, tight control of serum lipids in the group is necessary.