Incidence Rates of Ischemic Stroke in Diabetics: Preliminary Race-Specific Results from the Greater Cincinnati/Northern Kentucky Stroke Study
Intro: The Greater Cincinnati/Northern Kentucky Stroke Study provides epidemiologic data regarding stroke in blacks and whites. We present the incidence rates of ischemic stroke in diabetics. Methods: All strokes occurring between 1/1/93–12/31/93 for blacks and 7/1/93–12/31/93 for whites were identified by suveillance of ICD-9 discharge codes from hospitals (430–438, 1o or 2o), coroner’s records, and surveillance of outpatient settings previously described (Stroke 31; 280, 2000). Patient-medical encounters for all possible strokes/TIAs were reviewed and abstracted by a study nurse who determined diagnosis and stroke subtype using strict criteria (agreement with study physicians=87%, κ=0.71 on records completed by MD’s to date). For calculating incidence rates, the numerator consisted of cases determined to be a stroke by the study nurse. The denominator was calculated using self-reported age and gender specific rates of diabetes obtained from a 1995 random-digit dialing survey of 1850 study area residents proportionate to the stroke population (JAMA 279:1288–1292;1998). Reported incidence rates are adjusted to the 1990 US population. Conclusion: A preliminary analysis of our population-based study data reveals that diabetics have approximately a three-fold higher incidence of stroke as compared to non-diabetics, with slightly higher relative risk for whites. Diabetes is thus an important risk factor for ischemic stroke in both races although the prevelance of diabetes is higher in blacks.