New research published in BMJ Evidence-Based Medicine has shown that dementia risk appears to rise directly with alcohol consumption, with no safe level of alcohol consumption identified. Similar studies have shown that heart disease also rises in direct proportion to alcohol consumption. Both findings refute earlier claims that a small amount of alcohol may be protective for the heart and brain.
The study included nearly 560,000 adults in the U.S. and the U.K. who were 56 to 72 years old at the start of the study. The follow-up times were four years for U.S. participants and twelve years for U.K. participants. During the study, participants were monitored for the development of dementia and death. Additionally, the participants completed a questionnaire that determined how often they drank alcohol and whether they had hazardous drinking patterns, such as binge drinking. Finally, each participant underwent a genetic analysis. The goal of the study was to investigate the relationship between alcohol consumption and dementia risk.
The results showed that over 90% of the participants drank alcohol. When an analysis technique called Mendelian randomization genetic analysis was implemented, a direct correlation was seen between increased alcohol consumption and increased dementia risk. In particular, an extra 1–3 drinks per week was associated with a 15% higher risk. Additionally, doubling the genetic risk of alcohol dependency was associated with a 16% higher risk of developing dementia. Interestingly, the study further showed that people tended to drink less over time before they developed dementia, suggesting that early declines in cognition may lead to less drinking.
The authors noted that all alcohol drinking was associated with greater dementia risk, with no potential protective effect from drinking a small amount of alcohol. Previous studies have shown similar results for heart health, suggesting that there is no level of drinking that is healthier for the heart than not drinking. Reducing alcohol consumption may be an important component of reducing the risk of developing both heart disease and dementia.
Sources: Science Daily, BMJ Evidence-Based Medicine