Changes in alcohol consumption and risk of dementia in a nationwide cohort in South Korea

The impact of serial changes in alcohol consumption on dementia risk has rarely been investigated to date. A study investigated the association of comprehensive patterns of changes in alcohol consumption with the incidence of all-cause dementia, Alzheimer disease (AD), and vascular dementia (VaD). In a retrospective cohort study, data were obtained from the Korean National Health Insurance Service database. Adults aged 40 years and older underwent 2 health examinations in 2009 and 2011. The cohort was assessed until December 2018, and statistical analysis was performed in December 2021. Alcohol consumption level was categorised into none (0 g per day), mild (<15 g per day), moderate (15-29.9 g per day), and heavy (≥30 g per day) drinking. On the basis of changes in alcohol consumption level from 2009 to 2011, participants were categorised into the following groups: nondrinker, quitter, reducer, sustainer, and increaser. The primary outcome was newly diagnosed AD, VaD, or other dementia. Among 3,933,382 participants during a mean follow-up of 6.3 years, there were 100,282 cases of all-cause dementia, 79,982 cases of AD, and 11,085 cases of VaD. Compared with sustained nondrinking, sustained mild (adjusted hazard ratio [aHR], 0.79; 95% CI, 0.77-0.81) and moderate (aHR, 0.83; 95% CI, 0.79-0.88) drinking were associated with a decreased risk of all-cause dementia, whereas sustained heavy drinking was associated with an increased risk of all-cause dementia (aHR, 1.08; 95% CI, 1.03-1.12). Compared with sustained levels of drinking, reducing alcohol consumption from a heavy to a moderate level (aHR, 0.92; 95% CI, 0.86-0.99) and the initiation of mild alcohol consumption (aHR, 0.93; 95% CI, 0.90-0.96) were associated with a decreased risk of all-cause dementia. Increasers and quitters exhibited an increased risk of all-cause dementia compared with sustainers. The trends in AD and VaD remained consistent. The authors conclude that a decreased risk of dementia was associated with maintaining mild to moderate alcohol consumption, reducing alcohol consumption from a heavy to a moderate level, and the initiation of mild alcohol consumption, suggesting that the threshold of alcohol consumption for dementia risk reduction is low. Source: Jeon KH, Han K, Jeong S, et al. Changes in Alcohol Consumption and Risk of Dementia in a Nationwide Cohort in South Korea. JAMA Netw Open. 2023;6(2):e2254771.