Small deep cerebral infarcts: Is there synergism between hypertension and diabetes?

Diabetics have a stroke risk similar to that of nondiabetic hypertensives. The prevalence of hypertension is greater in diabetics than in nondiabetics, and hypertension is probably the principal cause of the increased stroke risk in diabetics. Diabetes itself, however, also contributes independently to the risk for stroke. It has recently been suggested that a synergistic interaction between diabetes and hypertension is a major contributor to the risk of stroke in diabetics. In order to look for synergistic interaction between diabetes and hypertension, we compared the frequency of small deep infarcts seen on computed tomography [small deep infarcts (SDIs)] between a group of diabetics and a group of nondiabetics individually matched for age, hypertension, and sex. There were no significant differences between diabetics and nondiabetics in the number or size of SDIs, the ventricular size, or the severity of paraventricular white matter lesions. This study is against the presence of a synergistic effect between diabetes and hypertension on small cerebral arteries and suggests that the majority of the risk for SDIs in diabetics is due to hypertension.