Heavy alcohol consumption — defined as 15 or more drinks per week for men and 8 or more drinks weekly for women, according to the Centers for Disease Control — increases the risk for many medical problems. Some of the known medical problems linked to alcohol include liver problems (cirrhosis and cancer), inflammation of the pancreas, high blood pressure and heart rhythm disturbances.
Stroke risk is also increased with heavy alcohol consumption. A recent study provided valuable information about the level of stroke risk associated with heavy alcohol consumption. Researchers followed a group of over 11,000 adults from the Swedish Twin Registry over a 43-year period. Alcohol consumption patterns were collected in this study and strokes were identified from participant medical records. Drinking three or more alcoholic drinks daily was linked to a 34% increase in risk for stroke during the follow-up period. Heavy drinking between the ages of 50 and 70 resulted in stroke occurring an average of five years earlier in the life cycle.
Twin studies are a powerful way to tease out genetic effects from environmental effects for medical problems. In this study, identical twins with heavy drinking showed greater risk for stroke compared to their identical twin who did not drink heavily. This finding supports heavy drinking as a stroke risk factor independent of genetic risk.
The exact mechanism for how heavy drinking increases stroke risk is unclear. But we do know that heavy alcohol consumption increases risk for bleeding, high blood pressure and a heart rhythm problem known as atrial fibrillation. Each of these factors is known to increase stroke risk.
Alcohol is not the only drug that increases risk for stroke. Cocaine use produces a rapid increase in stroke risk after use. One study found a seven-fold increase in the risk of stroke in the 24-hour period following cocaine use. Consuming alcohol and using cocaine at the same time likely contributes to an even greater stroke risk.
Medical complications related to alcohol dependence can be a powerful incentive for addiction treatment and abstinence. Stroke related to heavy drinking is a wake-up call for individuals to move to a healthier lifestyle. Stroke can produce irreversible effects on brain function that may persistent even following recovery from alcohol dependence. Making the smart choice for abstinence before suffering a stroke increases the chance for a full recovery and a healthy future.