Heavy Alcohol Use Increases Stroke Risk, Mortality

August 24, 2007 — Heavy consumption of alcohol has been linked to a significantly increased risk for stroke and stroke-related death in Chinese men.
In a large, population-based study of 64,338 men participating in the China National Hypertension Study, researchers at Tulane University School of Public Health and Tropical Medicine in New Orleans, Louisiana, found those who consumed 35 or more alcoholic drinks per week had a 22% increased risk for stroke and a 30% increased risk for stroke-related death vs nondrinkers.
"We found a progressive, nearly linear, increase in risk of stroke across the categories of drinking. It was significantly higher among individuals who consumed at least 35 drinks per week. But the risk was also increased in moderately heavy drinkers. So the risk was increased in those who were drinking more than 3 drinks per day and was greatly increased among those who consumed more than 5 drinks per day," principal investigator Lydia Bazzano, MD, PhD, told Medscape.
The study is published in the August 20 Online First issue of the Annals of Neurology.
Leading Cause of Death, Disability
In China, stroke is the leading cause of death in men and the leading cause of long-term disability. According to Dr. Bazzano, previous research has not completely clarified the link between the risk for stroke and alcohol consumption.
"We felt this study provided us with an excellent opportunity to look at this relationship in a population that has very high rates of stroke and stroke-related death," she said.
The prospective cohort study included men older than age 40 years who were free of stroke at the outset of the study. At baseline examination in 1991, participants provided information about their demographic characteristics, medical history, and lifestyle risk factors including alcohol consumption.
The follow-up evaluation, which was conducted from 1999 to 2000, included determining vital status, interviewing participants or proxies, and obtaining hospital and medical records for incident and fatal strokes.
Important Implications
During the course of the study, there were 3434 incident strokes and 1848 deaths from stroke. After adjusting for other risk factors including age, body mass index (BMI), physical activity, cigarette smoking, geographic variation, urbanization, history of diabetes, and education, researchers found alcohol consumption was significantly related to increased incidence of stroke as well as mortality.
"We know drinking alcohol can induce hypertension, so we expected to see some increased stroke risk in the highest category, but it was interesting to see this very linear correlation across the board between alcohol consumption and stroke risk," said Dr. Bazzano.
She added that the study's results have important public health implications that are likely generalizable to other populations.
"This study has shown that heavy, or even moderately heavy, drinkers have a much greater risk of stroke and stroke-related death than the general population. For this reason, doctors should advise patients who consume more than 3 alcoholic drinks per day to cut back," she said.
The authors have disclosed no relevant financial relationships.
Ann Neurol. Published online August 20, 2007.