Diabetic autonomic neuropathy is associated with an increased incidence of strokes

OBJECTIVE To ascertain risk factors associated with the occurrence of strokes in type 2 diabetes over a 5-year follow-up period. BACKGROUND Diabetic patients are at increased risk for cardiovascular disease when compared to non-diabetic patients. Strokes are a significant source of morbidity and mortality. DESIGN/METHODS We evaluated the relationship between a number cardiovascular risk factors in 950 normotensive and hypertensive type 2 diabetic patients enrolled in the Appropriate Blood Pressure Control in Diabetes (ABCD) trial on the incidence of stroke. We analyzed data from this longitudinal study to evaluate the relationships between various baseline risk factors and the occurrence of strokes. RESULTS A number of baseline risk factors were associated with the occurrence of strokes including history of a stroke (p=0.02) and heart failure (p=0.004) at baseline, age (p=0.004), longer duration of diabetes (p=0.03), higher systolic blood pressure (p=0.005), an abnormal ankle/brachial index (p=0.05), decreased duration on the exercise treadmill test at baseline (p=0.009), the presence of retinopathy (p=0.02), overt albuminuria (p=0.03) and the presence of diabetic autonomic neuropathy (DAN) as defined as a borderline or abnormal E/I ratio (p=0.016). Other variables that were tested but were not significantly associated included gender, duration of hypertension, diastolic blood pressure and smoking. When applying a multiple logistic regression model, DAN (OR=2.2, 95% CI=1.10-4.44), along with a history of heart failure (OR=7.4, 95% CI=2.12-26.15) and strokes (OR=3.4, 95% CI=1.02-11.00) at baseline were each associated with the occurrence of strokes. CONCLUSIONS In the present study of type 2 diabetic patients, DAN is a significant independent risk factor for the occurrence of stroke. This may occur due to accelerated cerebral vascular damage and alterations in the regulation of cerebral blood flow in diabetic patients with DAN.