Weekly alcohol consumption, cigarette smoking, and the risk of ischemic stroke: results of a case-control study at three urban medical centers in Chicago, Illinois.
To assess the role of current weekly alcohol consumption as a risk factor for cerebral infarction, we administered a pretested questionnaire to 205 middle-aged and elderly acute ischemic stroke patients and 410 outpatient controls matched by age, sex, race, and method of hospital payment. The frequency of hypertension (p less than 0.001) and transient ischemic attacks (p = 0.051), and mean weekly alcohol consumption (p = 0.0286) and mean pack-years cigarette exposure (p = 0.0168) were higher among stroke index cases than controls. For weekly alcohol consumption and mean pack-years cigarette exposure, there was a highly significant dose-response effect. In analyses to assess the possibility of mutual confounding effects of independent variables, we found hypertension and smoking to be independent risk factors for ischemic stroke, while alcohol consumption was not. Separate analyses by sex yielded similar results. We conclude that current weekly alcohol consumption may not be an independent risk factor for cerebral infarction in middle-aged and elderly patients.