Alcohol consumption, mild cognitive impairment, and progression to dementia

Objective: To estimate the impact of alcohol consumption on the incidence of mild cognitive impairment and its progression to dementia. Methods: We evaluated the incidence of mild cognitive impairment in 1,445 non-cognitively impaired individuals and its progression to dementia in 121 patients with mild cognitive impairment, aged 65 to 84 years, participating in the Italian Longitudinal Study on Aging, with a 3.5-year follow-up. The level of alcohol consumption was ascertained in the year before the survey. Dementia and mild cognitive impairment were classified using current clinical criteria. Results: Patients with mild cognitive impairment who were moderate drinkers, i.e., those who consumed less than 1 drink/day (approximately 15 g of alcohol), had a lower rate of progression to dementia than abstainers (hazard ratio [HR] 0.15; 95% CI 0.03 to 0.78). Furthermore, moderate drinkers with mild cognitive impairment who consumed less than 1 drink/ day of wine showed a significantly lower rate of progression to dementia than abstainers (HR 0.15; 95% CI 0.03 to 0.77). Finally, there was no significant association between higher levels of drinking (>= 1 drink/ day) and rate of progression to dementia in patients with mild cognitive impairment vs abstainers. No significant associations were found between any levels of drinking and the incidence of mild cognitive impairment in non-cognitively impaired individuals vs abstainers. Conclusions: In patients with mild cognitive impairment, up to 1 drink/day of alcohol or wine may decrease the rate of progression to dementia.