Association between alcohol drinking behaviour and cognitive function: results from a nationwide longitudinal study of South Korea

Objectives: This research intends to determine how drinking behaviour, such as episodic heavy drinking, is related to cognitive performance in middle-aged and old-aged people in South Korea. Methods: A cohort data of 5157 adults, age 45 years or older, with normal cognitive function (the Korean version of the Mini-mental state examination (K-MMSE) >= 24) at baseline (2006), was derived from the Korean Longitudinal Study of Aging. Alcohol drinking behaviour was assessed using the CAGE (Cut down, Annoyed, Guilty, Eye-opener) questionnaire. The relationships between baseline drinking behaviour (in 2006) to the extent of cognitive decline (between 2006 and 2012) and development of cognitive impairment (in 2012) were assessed. Results: Individuals with problematic drinking behaviour at baseline experienced a faster decline in cognitive function than those with non-problematic drinking (p<0.05) during 6 years of follow-up, especially among those with relatively low-normal K-MMSE score (24-26) at baseline (p<0.05). Problematic alcohol drinking behaviour was also significantly associated with onset of severe cognitive impairment (SCI) (K-MMSE score <= 17) among those with relatively low-normal K-MMSE score (adjusted OR (aOR)=3.76, 95% CI 1.46 to 9.67). In addition, abstinence, compared with non-problematic drinking, was related to higher risk for developing SCI among men (aOR=1.62, 95% CI 1.09 to 2.39). Conclusions: Our results suggest that those with problematic alcohol drinking behaviour could be at an increased risk of cognitive impairment/decline. While further research will provide stronger evidence, intervention targeting alcohol abuse may play a role in prevention of cognitive impairment.