To investigate to which extent differences in cardiovascular risk factors explain the increased risk of myocardial infarction (MI) and complication rate in women with diabetes mellitus (DM). Case-control study. We compared women with diabetes and previous MI (n=29), diabetes but no MI (n=46), prior MI but no diabetes (n=64), and healthy controls (n=125). Smoking habits, physical activity, blood pressure (BP), body mass index (BMI), waist/hip ratio (WHR), serum lipids, plasma fibrinogen, and serum sex hormones. Despite the fact that diabetic women had similar BMI, those with a past MI, compared to diabetic women without MI, had significantly higher WHR (mean, 95% CI) [0.89 (0.87, 0.92) vs. 0.84 (0.81, 0.86) mmol/l, P=.001] and very high S-triglycerides [3.03 (2.23, 3.83) vs. 1.69, (1.39, 1.99) mmol/l, P=.001] and low HDL-cholesterol [1.09 (0.94, 1.24) vs. 1.56 (1.41, 1.71) mmol/l, P<.001], indicating pronounced metabolic disturbances. Women with MI but no diabetes had intermediate values for WHR, triglycerides, and HDL-cholesterol. Furthermore, women with diabetes and MI had significantly higher p-fibrinogen, were smokers, and lived a more sedentary life than the other women. Over half of all women with prior MI were on lipid-lowering therapy and tended to have nonsignificantly lower S-cholesterol than women without MI. Women with diabetes who have manifested an MI carry a very substantial cardiovascular risk factor burden, which probably explain their increased morbidity and mortality. In order to improve prognosis, studies targeted at investigating treatment modalities for these abnormalities are needed.