Is diabetes mellitus a cardiovascular disease risk equivalent for fatal stroke in women? Data from the Women's Pooling Project

Abstract

Background and purpose: Diabetes mellitus is an independent risk factor for stroke and is associated with a 1.8- to approximately 6-fold increased risk compared with nondiabetic subjects. Recent guidelines have classified diabetes as a coronary heart disease risk equivalent. Whether diabetes is a cardiovascular disease risk equivalent for stroke is not established.

Methods: Data were pooled from 9 prospective epidemiological studies in the United States. We followed up 27,269 women (8.5% diabetic, 2.9% with prior myocardial infarction, 2.3% with prior stroke) for an average of 8.3 years, during which 238 stroke deaths were observed.

Results: Both diabetic subjects without cardiovascular disease and nondiabetic subjects with history of prior stroke had a significantly increased risk of 10-year stroke mortality compared with nondiabetic subjects without prior cardiovascular disease (hazard ratio [HR], 6.77; 95% confidence interval [CI], 4.56 to 10.05; HR, 3.37; 95% CI, 2.38 to 4.77). History of prior myocardial infarction was not associated with long-term stroke mortality (HR, 0.66; 95% CI, 0.27 to 1.61). After adjustment for risk factors, diabetic subjects had similar risk compared with subjects with a history of prior stroke (HR, 1.29; P=0.43).

Conclusions: Diabetic subjects without cardiovascular disease have a fatal stroke risk similar to that of nondiabetic subjects with a history of prior stroke and similar risk factor profile. This suggests that diabetes mellitus may be classified as a stroke risk equivalent and may warrant more aggressive treatment strategies in the future prevention of stroke.