IMPORTANCE: The impact of serial changes in alcohol consumption on dementia risk has rarely been investigated to date. OBJECTIVE: To investigate the association of comprehensive patterns of changes in alcohol consumption with the incidence of all-cause dementia, Alzheimer disease (AD), and vascular dementia (VaD). DESIGN, SETTING, AND PARTICIPANTS: This is 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 31, 2018, and statistical analysis was performed in December 2021. EXPOSURES: Alcohol consumption level was categorized into none (0 g per day), mild (/=30 g per day) drinking. On the basis of changes in alcohol consumption level from 2009 to 2011, participants were categorized into the following groups: nondrinker, quitter, reducer, sustainer, and increaser.
MAIN OUTCOMES AND MEASURES: The primary outcome was newly diagnosed AD, VaD, or other dementia.
RESULTS: Among 3 933 382 participants (mean [SD] age, 55.0 [9.6] years; 2 037 948 men [51.8%]), during a mean (SD) follow-up of 6.3 (0.7) 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. CONCLUSIONS AND RELEVANCE: In this cohort study of a Korean population, 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.
BACKGROUND: The identification of effective dementia prevention strategies is a major public health priority, due to the enormous and growing societal cost of this condition. Consumption of a Mediterranean diet (MedDiet) has been proposed to reduce dementia risk. However, current evidence is inconclusive and is typically derived from small cohorts with limited dementia cases. Additionally, few studies have explored the interaction between diet and genetic risk of dementia.
METHODS: We used Cox proportional hazard regression models to explore the associations between MedDiet adherence, defined using two different scores (Mediterranean Diet Adherence Screener [MEDAS] continuous and Mediterranean diet Pyramid [PYRAMID] scores), and incident all-cause dementia risk in 60,298 participants from UK Biobank, followed for an average 9.1 years.
The interaction between diet and polygenic risk for dementia was also tested. RESULTS: Higher MedDiet adherence was associated with lower dementia risk (MEDAS continuous: HR = 0.77, 95% CI = 0.65-0.91; PYRAMID: HR = 0.86, 95% CI = 0.73-1.02 for highest versus lowest tertiles). There was no significant interaction between MedDiet adherence defined by the MEDAS continuous and PYRAMID scores and polygenic risk for dementia. CONCLUSIONS: Higher adherence to a MedDiet was associated with lower dementia risk, independent of genetic risk, underlining the importance of diet in dementia prevention interventions.
BACKGROUND: Previous studies on associations of alcohol use with memory decline showed inconclusive results. We examined these associations using longitudinal data from the Guangzhou Biobank Cohort Study (GBCS) and explored whether these associations varied by sex and age group.
METHODS: Memory function was assessed by delayed 10-word recall test (DWRT) and immediate 10-word recall test (IWRT) at both baseline (2003-2008) and follow-up (2008-2012) examinations, expressed as the mean annual change and mean annual rate of change in scores. Memory cognitive impairment was defined by DWRT scores of less than 4. Multivariable linear regression models and restricted cubic spline were used for data analysis.
RESULTS: Of 14,827 participants without memory cognitive impairment at baseline, 90.2% were never or occasional drinkers, 5% moderate drinkers, 1.5% excessive drinkers, and 3.3% former drinkers. The mean (standard deviation) age was 60.6 (6.6) years old. During an average of 4.1 years follow-up, 1000 (6.7%) participants developed memory cognitive impairment. After adjusting for confounders, compared with never or occasional drinkers, moderate and excessive drinkers had significant decline in DWRT scores (beta, 95% confidence interval (CI) = -0.04 (-0.08 to -0.01), and - 0.07 (-0.14 to 0.01), respectively), and IWRT scores (beta, 95% CI = -0.10 (-0.19 to -0.01), and - 0.15 (-0.30 to 0.01), respectively) annually. With respect to the mean annual rate of change, moderate and excessive drinkers also showed greater decline in DWRT scores (beta, 95% CI = -1.02% (-1.87% to -0.16%), and - 1.64% (-3.14% to -0.14%), respectively). The associations did not vary by sex and age group (all P values for interaction >/= 0.10).
CONCLUSION: Compared to never or occasional alcohol use, moderate and excessive alcohol users had greater memory decline and the associations did not vary by sex and age group.
BACKGROUND: Evidence for late-life alcohol consumption being associated with reduced dementia risk is largely based on cohort studies of predominately non-Hispanic white older adults. Our objective was to investigate the relationship between late-life alcohol consumption and dementia risk among Mexican-America adults aged 75 and older.
METHODS: This study was a retrospective analysis of waves 5 (2004/05) to 8 (2012/13) of the Hispanic Established Populations for the Epidemiologic Study of the Elderly. The final sample included 1,255 participants. Late-life alcohol consumption status was classified as life-long abstainer, former drinker, and current drinker. Dementia was defined as a score of 18 points or lower on the Mini-Mental Status Examination or a proxy-reported diagnosis of dementia. Results: 41.8% of participants were life-long abstainers, 42.0% were former drinkers, and 16.3% were current drinkers. Current alcohol consumers had significantly lower dementia risk compared to life-long abstainers (HR=0.63, 95% CI = 0.44-0.89). Dementia risk for former alcohol consumers compared to life-long abstainers was not statistically significant (HR = 0.85, 95% CI = 0.67-1.09).
CONCLUSIONS: Current alcohol consumption was associated with lower dementia risk for Mexican Americans aged 75 and older. Continued research is needed to identify pathways for the protective association between late life alcohol consumption and dementia risk.