VANCOUVER—Moderate alcohol consumption or binge drinking in late life may increase the risk of cognitive impairment, according to two studies presented at the 2012 Alzheimer’s Association International Conference. The studies, one conducted in older adults and one in older women, shed additional light on how alcohol use may affect the likelihood of dementia onset.
Moderate Drinking Late in Life May Increase Women’s Dementia Risk
Women who drank more heavily earlier in life than at baseline, women who drank moderately in late life, and nondrinking women who began drinking in late life had an increased risk of cognitive impairment, according to Tina Hoang, MSPH, Research Associate at NCIRE/The Veterans Health Research Institute in San Francisco. Moderate drinking (defined as consuming seven to 14 drinks per week) did not protect older women against cognitive impairment.
Ms. Hoang and her colleagues studied 1,306 women age 65 or older in a prospective cohort study. Participants reported the frequency of their current and past alcohol consumption at baseline, and the researchers reassessed participants’ alcohol use at years six, eight, 10, and 16 of the study. Participants were followed for 20 years. Clinically significant cognitive impairment, including mild cognitive impairment and dementia, was adjudicated by an expert panel at the end of the study.
The mean age of participants at baseline was 68.3. Nearly 41% of the women were nondrinkers, about 51% were light drinkers (ie, drank as many as seven drinks per week), and 9% were moderate drinkers. Women who drank more than 14 drinks per week were excluded from the study.
Participants who reported drinking more in the past than at baseline had a 30% increased risk of cognitive impairment. Women who drank moderately at baseline or at the midpoint of the study had a risk of cognitive impairment similar to that of nondrinkers. Women who drank moderately late in life had a 62% increased risk of cognitive impairment. Nondrinkers who began drinking during follow-up had a 200% increased risk of cognitive impairment.
“We’re not entirely sure of the mechanisms associated with moderate alcohol use and increased risk in late life observed in our study,” Ms. Hoang told Neurology Reviews. “One hypothesis is that other factors associated with late-life alcohol use increase the risk of cognitive impairment, and another is that the brains of the oldest adults may be more vulnerable to the effects of alcohol use,” she added.
Binge Drinking Late in Life May Harm Cognition and Memory
Older adults who reported binge drinking one or more times per month were 62% more likely to have the greatest 10% of decline in cognitive function and 27% more likely to have the greatest 10% of decline in memory, according to Iain Lang, PhD, Consultant in Public Health at University of Exeter Medical School in Exeter, United Kingdom. When analyzed separately, outcomes were similar for men and women.
Dr. Lang and colleagues analyzed data from 5,075 participants in the US Health and Retirement Study who were age 65 or older. Baseline data were collected in 2002, and participants were followed up for eight years. Researchers assessed participants’ level of alcohol consumption and level of heavy episodic drinking (ie, consumption of four or more drinks on one occasion) at baseline. Models were adjusted for several variables, including age, sex, and mean number of drinks per day. The primary outcomes, change in cognitive function and memory, were evaluated through the Telephone Interview of Cognitive Status.
Approximately 8% of men reported binge drinking an average of once per month or more, compared with 1.5% of women. Binge drinking twice per month or more was reported by 4.3% of men and 0.5% of women. Binge drinking two or more times per month was associated with a 147% increased likelihood of having the greatest 10% of decline in cognitive function and a 149% increased likelihood of having the greatest 10% of decline in memory among older adults.
“Everyone concerned … needs to be aware that binge drinking in later life can have potential adverse outcomes,” Dr. Lang told Neurology Reviews. “Clinicians speaking to a patient where there is a concern about alcohol consumption need to be aware that it’s not just overall level of alcohol consumption—number of drinks consumed per week—that is significant, but also the pattern of drinking, with binging obviously being of particular note,” he added.
—Erik Greb