A study funded by the National Institute on Alcohol Abuse and Alcoholism sought to investigate the risks and benefits of moderate drinking through analyzing and comparing hospital records of residents in dry, wet, and dry-to-wet counties in Texas.
Gregory Marcus, associate professor of medicine at the University of California, San Francisco and senior author of the study, treats patients with atrial fibrillation. Atrial fibrillation is an abnormal heart rhythm, which can cause blood to pool in the left atrium of the heart, with a risk of clotting, which can cause stroke. It is the most common type of arrhythmia.
Dr. Marcus says, “Patients will ask me, ‘Is it ok to drink alcohol?’ ‘Isn’t it a good idea to have a little red wine for your heart?’”
The answer, it seems, is not so straightforward, as the effect of moderate drinking on atrial fibrillation is not clear, partially because most research on the risks of benefits of moderate drinking is not conducted through randomized trials, reports The Wall Street Journal. Inaccuracies stem from patients self-reporting the amount of alcohol they consume, and as a result studies have produced conflicting results.
On the new study Dr. Marcus says, “We saw this as an opportunity to approach the question in a completely different way.” Dr. Marcus and his colleagues analyzed hospital records gathered from a state database between January 1, 2005 and December 31, 2009. During these years 47 Texas counties were wet, 29 were dry, and seven switched from dry to wet.
In wet counties, where alcohol sales are allowed, hospital records showed “significantly higher misuse of alcohol and cases of alcoholic liver disease.” The prevalence of atrial fibrillation was about 5 percent higher in wet counties — but the prevalence of heart attacks was 17 percent lower. Hospitalization rates for atrial fibrillation were 7 percent higher and for heart attacks 9 percent lower in the wet counties. For the counties that switched from dry to wet, risk for atrial fibrillation was also 7 percent higher.
Though the study demonstrated a higher risk for atrial fibrillation in the longtime and newly-wet counties, the study does not take into account the amount of alcohol consumed and how this increases or decreases risk.