Stroke in the diabetic and non-diabetic population in Germany: relative and attributable risks, 2005-2007

Reduction of cardiovascular events has been declared to be a main objective in diabetes care. Little is known about incidences of stroke in the diabetic compared to the non-diabetic population and its trend. We evaluated nationwide incidence of stroke in the diabetic compared to the non-diabetic populations as well as relative and attributable stroke risks due to diabetes in Germany.

Using data of a statutory health insurance (1.6 million members in Germany), we assessed all first strokes in 2005-2007. We estimated sex/age-specific and standardised incidence of strokes in the diabetic and non-diabetic populations and relative and attributable risks due to diabetes.

A total of 6160 subjects had a first stroke [66.6% male, mean age (S.D.)=67.0 (13.9) years]; 31.4% had diabetes. Incidence per 100,000 person years (standard: 2004 German population) in the diabetic and non-diabetic populations, respectively, is as follows: men: 476 [95% confidence interval (CI)=438-514] and 255 (95% CI=243-266); women: 342 (95% CI=305-378) and 173 (95% CI=163-182). Age-standardised relative risks are as follows: 1.9 (95% CI=1.7-2.0) in men and 2.0 (95% CI=1.8-2.2) in women. The following are attributable risks among exposed: 0.46 (95% CI=0.41-0.51) in men and 0.49 (95% CI=0.43-0.55) in women; population attributable risks are as follows: 0.14 (95% CI=0.11-0.16) in men and 0.14 (95% CI=0.11-0.17) in women.

In this nationwide study, we found the stroke risk in the diabetic population to be still significantly increased compared to the non-diabetic population. The risk increase seems to be as high as earlier observations in other countries, despite large efforts to improve diabetes care.