Heavy Alcohol Use May Triple Dementia Risk
By Pauline Anderson
July 18, 2019
LOS ANGELES — Older female veterans who have alcohol use disorder (AUD) are at a threefold increased risk of developing dementia compared to their counterparts without AUD, new research shows.
Although AUD is a growing concern in all veterans, it has been unclear if this disorder raises dementia risk in female veterans.
“Nobody has looked at this before. Female veterans are a unique group because they are increasing in numbers, and it is a population that is getting older,” study investigator Amber L. Bahorik, PhD, research project coordinator in psychiatry, University of California, San Francisco (UCSF), told Medscape Medical News.
The results have implications for screening and prevention, she added.
The findings were presented here at the Alzheimer’s Association International Conference (AAIC) 2019.
J-Curve
Research shows that the impact of alcohol consumption on the risk for various diseases depends on the amount consumed. For example, statistically, alcohol consumption has a J-shaped effect on the relative risk for heart disease, stroke, and diabetes. Moderate consumption reduces risk, and excess use markedly increases risk.
The same may apply to the effects of alcohol consumption regarding dementia.
“If you drink moderately, that might have a protective effect on dementia risk, but excessive alcohol consumption might have a bad effect — although this area is controversial,” said Bahorik.
The study included 2207 women aged 55 years or older (mean age, 60 years) who had current AUD and 2207 age-matched control persons who did not have AUD. The participants attended Veterans Affairs (VA) centers in the United States from October 2004 to September 2015.
AUD was diagnosed using the International Classification of Diseases 9th Revision Clinical Modification Codes (ICD-9). The condition, which is defined as a problematic pattern of drinking accompanied by clinical impairment or distress, is a growing concern among older veterans, especially women.
Hazardous drinking has a “slightly lower threshold,” said Bahorik. Women who consume more than four alcoholic drinks per day “would be flagged as a hazardous or problematic drinker.” For men, the threshold is more than five drinks per day, she said.
The outcome of the study was incident dementia diagnosed using ICD-9 codes during 7 years of follow-up.
The study showed that female veterans with AUD were more than three times more likely to develop dementia than female veterans who did not have AUD (hazard ratio, 3.06; 95% confidence interval, 1.83 – 5.13).
The findings were adjusted for demographics as well as for depression, anxiety, posttraumatic stress disorder, smoking, hypertension, diabetes, stroke, chronic obstructive pulmonary disease, and traumatic brain injury.
Bahorik presented data that showed that women veterans with AUD developed dementia at a faster rate than those without AUD.
Other research has found that the rate of AUD is higher in male veterans than in female veterans. “I don’t know what the dementia risk is in male vets with AUD, but presumably that would be higher, too,” said Bahorik.
Ask About Drinking
It is important for clinicians to ask patients about their drinking habits as well as smoking and other unhealthy behaviors, the study’s principal investigator, Kristine Yaffe, MD, professor of neurology, psychiatry, and epidemiology, UCSF, told Medscape Medical News.
“If you’re concerned about someone having an alcohol use disorder or risky behavior, there are some pretty good treatment programs, particularly at the VA, so you can refer patients there,” she said.
Commenting on the study for Medscape Medical News, Heather Snyder, PhD, senior director of medical and scientific operations, the Alzheimer’s Association, said the work is “interesting” and “very important” in that it investigated how behaviors or habits in “a defined population” of female veterans may influence later-life risk for dementia.
“To my knowledge, this is one of the first studies of its kind that we have seen in this specific population,” she said.
The results could help with targeting interventions, said Snyder.
Bahorik, Jaffe, and Snyder have disclosed no relevant financial relationships.
Alzheimer’s Association International Conference (AAIC) 2019: Abstract 32612. Presented July 14, 2019.