The overall 5-year mortality of non-insulin-dependent diabetes mellitus (NIDDM) patients aged under 65 years and associated risk factors were examined with a population-based study in a primary care setting. At the baseline, diabetic patients were asked of existing coronary heart disease (CHD) and hypertension, and checked for body mass index (BMI), glycemic control, lipid values and overnight albuminuria. Of 381 identified NIDDM patients, 252 (66%) participated in the study. The median age was 58 (range 36-64) years, BMI 30.5 (S.D. 5.5) kg/m2 and glycosylated hemoglobin A1c 8.7 (S.D. 2.0)%. Overall 5-year mortality was 8.3%. Factors associated with mortality were male gender, low high-density lipoprotein cholesterol, initial CHD and albuminuria > or = 20 microg/min. In Cox regression analysis, combination of CHD and albuminuria had the highest relative risk for mortality (RR = 3.43, 95% CI 1.63-7.19, P = 0.001), adjusted for gender and age. Albuminuria was associated with CHD only in male NIDDM patients. In primary health care, physicians should be aware that combination of CHD and (micro)albuminuria is a major predictor of mortality in NIDDM patients.