OBJECTIVE: We studied the 15-year cardiovascular mortality and morbidity of newly diagnosed patients with type 2 diabetes and of nondiabetic control subjects and the predictors of cardiovascular mortality in diabetic patients. RESEARCH DESIGN AND METHODS: We performed a 15-year prospective study of 133 middle-aged patients with newly diagnosed type 2 diabetes and 144 control subjects. Cardiovascular risk factors were assessed in both groups at baseline and after 5 and 10 years. RESULTS: Total mortality was markedly higher in patients with type 2 diabetes (total: 44.3 vs. 12.9% for men, age-adjusted odds ratio [OR] 5.0, P < 0.001; 44.4 vs. 11.0% for women, OR 5.2, P < 0.001), which was due to increased cardiovascular mortality (ORs for men and women: 6.2 and 11.2, respectively, P < 0.001 for both). The incidences of fatal and nonfatal myocardial infarction and stroke were likewise higher in diabetic patients. In univariate analyses and various multiple logistic regression analyses, hyperglycemia was a constant predictor of cardiovascular mortality assessed at the time of diagnosis or at 5- or 10-year examinations. Moreover, lipoprotein abnormalities characteristic of type 2 diabetes (low HDL cholesterol, high LDL triglycerides or apolipoprotein B levels, and low LDL cholesterol/apolipoprotein B ratio as a marker for LDL size) were predictive of cardiovascular death in these analyses. CONCLUSIONS: This long-term study of a well-characterized group of newly diagnosed patients strengthens the view that the prognosis in middle-aged subjects is markedly impaired and that both hyperglycemia and compositional lipoprotein abnormalities are predictors of cardiovascular mortality in patients with type 2 diabetes.