“The rate of stroke among young adults has been increasing over the last few decades, and stroke in young adults causes death and serious disability,” study coauthor Eue-Keun Choi, MD, PhD, of Seoul National University, Republic of Korea, said in a statement.
“If we could prevent stroke in young adults by reducing alcohol consumption, that could potentially have a substantial impact on the health of individuals and the overall burden of stroke on society,” Dr. Choi added.
The study was published online in Neurology.
Compounding effects
Using data from a Korean national health database, the researchers identified roughly 1.5 million adults aged 20-39 years (mean age 29.5 years, 72% male) who had four consecutive annual health examinations during which they were asked about their alcohol use.
During a median follow-up of roughly 6 years, 3,153 individuals suffered a stroke.
After multivariate adjustment accounting for other factors that could affect the risk for stroke, such as hypertension, smoking, and body mass index, the risk of stroke increased steadily with the number of years of moderate to heavy drinking, defined as 105 grams or more of alcohol per week.
Compared with light drinkers or teetotalers, stroke risk increased 19% with 2 years of moderate to heavy drinking and 22% and 23%, respectively, for 3 and 4 years of moderate or heaving drinking.
The positive dose-response relationship was chiefly driven by increased risk of hemorrhagic stroke; with 2, 3 and 4 years of moderate to heavy drinking, hemorrhagic stroke risk increased 30%, 42% and 36%, respectively, relative to light/no drinking.
“Since more than 90% of the burden of stroke overall can be attributed to potentially modifiable risk factors, including alcohol consumption, and since stroke in young adults severely impacts both the individual and society by limiting their activities during their most productive years, reducing alcohol consumption should be emphasized in young adults with heavy drinking habits as part of any strategy to prevent stroke,” Dr. Choi said.
A limitation of the study is that only Korean people were included, so the results may not apply to people of other races and ethnicities, they noted. In addition, people filled out questionnaires about their alcohol consumption, which may introduce recall bias.
Consistent evidence
“For decades, the evidence was suggestive that a moderate amount of alcohol daily is actually beneficial – one to two drinks in men and one drink in women – at reducing major vascular outcomes,” Pierre Fayad, MD, professor, department of neurological sciences, and director of the Nebraska Stroke Center, University of Nebraska Medical Center, Omaha, said in commenting on the research.
Yet, over the past few years, some research has found no evidence of benefit with moderate alcohol intake. There is, however, “consistent evidence” that shows a detrimental effect of excessive alcohol, particularly binge drinking, especially in young adults, Dr. Fayad said.
This study, he said, “adds to the known detrimental effects of excessive alcohol intake, in increasing the risk of stroke, particularly in young adults.
“The bottom line: Young adults who usually have a low risk of stroke increase their risk significantly by heavy alcohol drinking, and Koreans are equally at risk as other populations,” Dr. Fayad said.
The study was supported by the Korea Medical Device Development Fund and the Korea National Research Foundation. Dr. Choi and Dr. Fayad report no relevant financial relationships.
A version of this article first appeared on Medscape.com.