Alcohol consumption and incident dementia in older Japanese adults: The Okayama Study

Abstract

Aim To evaluate the association between the amount and frequency of alcohol consumption and incident dementia in older Japanese adults using large sample size data over a long follow‐up period. Methods This was a retrospective cohort study carried out in Japan. A total of 53 311 older adults were followed from 2008 to 2014. A health checkup questionnaire was used to assess the amount and frequency of alcohol consumption. The Dementia Scale of long‐term care insurance was used as a measure of incident dementia. Cox proportional hazards models were used to calculate adjusted hazard ratios, with their 95% confidence intervals, for the incidence of dementia across the categories of alcohol consumption by sex. Results During a 7‐year follow‐up period, 14 479 participants were regarded as having incident dementia. Compared with non‐drinkers, the multivariate adjusted hazard ratios for participants with alcohol consumption ≤2 units per day, occasionally (0.88, 95% CI 0.81–0.96 in men and 0.84, 95% 0.79–0.90 in women) and daily (0.79, 95% 0.73–0.85 in men and 0.87, 95% 0.78–0.97 in women) were statistically significant, and the difference between occasional and daily consumption was only statistically significant in men; however, for participants with alcohol consumption >2 units per day, occasionally (0.91, 95% 0.71–1.16 in men and 1.09, 95% 0.72–1.67 in women) and daily (0.89, 95% 0.81–1.00 in men and 1.16, 95% 0.84–1.81 in women) were not significant. Conclusions Alcohol consumption of ≤2 units per day, occasionally or daily, could reduce the risk of incident dementia, with greater benefit for men with such daily consumption. Geriatr Gerontol Int 2019; 19: 740–746.

A systematic review of self-report measures used in epidemiological studies to assess alcohol consumption among older adults

“…In four studies, a standard drink or unit was defined as 13 and 15 grams of alcohol, respectively, while six studies defined a standard drink or unit as 14 grams of alcohol. Studies conducted in China [ 109 ] and Japan [ 59 , 70 , 111 ] defined a standard drink of unit as 50 grams of alcohol [ 109 ] and 20–23 grams of alcohol [ 59 , 70 , 111 ], respectively. Three studies used several definitions of one standard drink [ 59 , 99 , 118 ], whereas two studies defined the alcohol content in one drink in ounces [ 60 , 88 ].…”

Development of the Korean Health Behavior for Dementia Prevention Scale for Older Adults

“…The components were non-smoking and moderate drinking. In a sevenyear cohort study by Liu et al [33], the non-drinkers showed a .79-and .87-times lower risk of dementia for men and women, respectively, compared to individuals who drank daily. Drinking more than one drink per day would increase the risk of dementia.…”

Association between the occurrence of albuminuria and the risk of early dementia among older people upon health examination: a community-based cohort study in Taiwan

“…One study reported that alcohol consumption of ≤2 units/day (one unit is defined as a beverage containing approximately 20 g alcohol) could reduce the risk of dementia among older Japanese adults. 34 However, a previous review reported a dose-response effect of alcohol consumption on the deterioration of cognitive function. Frequent heavy alcohol consumption may damage brain function and decrease cognitive functions, whereas light to moderate alcohol consumption has protective effects.…”