The aim of this study was to investigate the risk of acute stroke in subgroups of patients treated for hypertension and type 2 diabetes in primary care. Patients with hypertension only (n = 695), type 2 diabetes only (n = 181) or both (n = 240), who consecutively attended an annual control in primary care in Skara, Sweden during 1992-1993, were evaluated for cardiovascular disease risk factors and enrolled in this study. Subjects with neither hypertension nor type 2 diabetes (n = 824) who participated in a population survey in the same community served as controls. Possible events of acute stroke through 2002 were validated using hospital records and death certificates. During a mean follow-up time of 8.4 years, 190 first events of acute stroke, fatal or non-fatal, were ascertained. Risk factor levels were generally higher in all patient categories than in controls. Stroke risk was significantly increased in all male patients: hazard ratio 4.2 (95% CI 2.1-8.4) in patients with both conditions, 3.3 (1.5-7.0) in those with type 2 diabetes alone and 2.8 (1.5-5.3) in those with hypertension alone (adjusted for age, total cholesterol, current smoking, BMI and physical activity). Corresponding findings in women were 2.9 (1.5-5.8) in patients with type 2 diabetes only and 2.4 (1.2-4.7) in those with both conditions. However, in women with hypertension only, a significant risk was seen first when subjects were truncated at 85 years of age. There were too few fatal stroke events for conclusive results on stroke mortality. A considerable risk of acute stroke remains in patients with type 2 diabetes and hypertension. Strategies for stricter multiple risk factor interventions should be implemented in primary care.