Late-Life Binge Drinking May Increase Risk of Cognitive Decline
Light to moderate alcohol consumption has generally been considered to have some health benefits, including possibly reducing the risk of cognitive decline. However, two studies reported at last month’s Alzheimer’s Association International Conference in Vancouver suggest that moderate alcohol use in late life, heavier use earlier in life, and binge drinking in late life increase the risk of cognitive decline.
“The many dangers of misuse of alcohol and some of its possible benefits have been widely reported, and there needs to be further clarification by the scientific community,” said William Thies, PhD, the Alzheimer's Association chief medical and scientific officer. “Certainly no one should start drinking in order to reduce Alzheimer’s risk, as these two new reports attest.
“We need to know more about what factors actually raise and lower risk for cognitive decline and Alzheimer’s disease,” he continued. “To do that, we need longer-term studies in larger and more diverse populations, and we need more research funding to make that happen. We have learned incredible amounts about heart disease and stroke risk from long-term research like the Framingham Study; we have solidly proven lifestyle risk factors that people can act on every day. Alzheimer’s now needs its version of that research.”
Whether moderate alcohol consumption has an impact on cognitive impairment in later life is unsettled with some studies suggesting a protective effect. To date, few studies have examined patterns of alcohol consumption over time in relation to cognitive status, especially in very late life.
Tina Hoang, MSPH, of NCIRE/The Veterans Health Research Institute in San Francisco and the University of California, San Francisco, and her colleagues followed more than 1,300 women aged 65 and older for 20 years. They measured the frequency of current and past alcohol use at the beginning, midpoint (years six and eight), and late phases (years 10 and 16) of the study. At the end of the study, the researchers assessed participants for mild cognitive impairment and dementia. At baseline, 40.6% were nondrinkers, 50.4% were light drinkers (zero to seven drinks per week), and 9% were moderate drinkers (seven to 14 drinks per week). Heavy drinkers (14 drinks per week) were excluded.
The scientists’ findings included the following:
• Women who reported drinking more in the past than at the beginning of the study were at 30% increased risk of developing cognitive impairment.
• Moderate drinkers at baseline or midpoint had similar risks of cognitive impairment to nondrinkers; however, moderate drinkers in the late phase of the study were roughly 60% more likely to develop cognitive impairment.
• Women who changed from nondrinking to drinking over the course of the study had a 200% increased risk of cognitive impairment.
“In this group of older women, moderate alcohol consumption was not protective,” Hoang said. “We found that heavier use earlier in life, moderate use in late life, and transitioning to drinking in late life were associated with an increased risk of developing cognitive impairment. These findings suggest that alcohol use in late life may not be beneficial for cognitive function in older women.
“It may be that the brains of oldest old adults are more vulnerable to the effects of alcohol, but it is also possible that factors associated with changing alcohol use related to coping or loss could be involved,” Hoang added. “Clinicians should carefully assess their older patients for both how much they drink and any changes in patterns of alcohol use.”
Little is known about the cognitive effects of heavy episodic or binge drinking in older people. Binge drinking is a pattern of alcohol consumption in which someone who is not otherwise a heavy drinker consumes several drinks on one occasion.
“We know that binge drinking can be harmful,” said Dr Iain Lang of Peninsula College of Medicine and Dentistry at the University of Exeter in the United Kingdom. “For example, it can increase the risk of harm to the cardiovascular system, including the chance of developing heart disease, and it is related to increased risk of both intentional and unintentional injuries.”
According to Lang, it is not clear whether binge drinking in older adults has a damaging effect on cognitive health and whether it increases the risk a person will develop dementia.
To assess the effects on cognition and mood of US adults aged 50 and older, Lang and colleagues conducted a secondary analysis of data from 5,075 participants aged 65 and older in the Health and Retirement Study, a biennial longitudinal nationally representative survey. Baseline data were collected in 2002, and participants were followed for eight years. Consumption of four or more drinks on one occasion was considered binge drinking. Cognitive function and memory were assessed using the Telephone Interview for Cognitive Status.
Binge drinking once per month or more frequently was reported by 8.3% of men and 1.5% of women; 4.3% of men and 0.5% of women reported binge drinking twice per month or more frequently.
Researchers’ findings included the following:
• Participants who reported heavy episodic drinking once per month were 62% more likely to be in the group experiencing the highest decline in cognitive function and were 27% more likely to be in the group experiencing the highest amount of memory decline.
• Participants reporting heavy episodic drinking twice per month or more were 147% more likely to be in the group experiencing the highest decline in cognitive function and were 149% more likely to be in the group experiencing the highest amount of decline in memory.
Outcomes were similar in men and women when analyzed separately.
“In our group of community-dwelling older adults, binge drinking is associated with an increased risk of cognitive decline,” Lang said. “Those who reported binge drinking at least twice a month were more than twice as likely to have the greatest decline in both cognitive function and memory. These differences were present even when we took into account other factors known to be related to cognitive decline such as age and level of education.
“This research has a number of implications. First, older people and their physicians should be aware that binge drinking may increase their risk of experiencing cognitive decline and encouraged to change their drinking behaviors accordingly. Second, policy makers and public health specialists should know that binge drinking is not just a problem among adolescents and younger adults; we have to start thinking about older people when we are planning interventions to reduce binge drinking," Lang said.
— Source: Alzheimer’s Association