Abstract
Background/Objectives: Precise prevention strategies for mild cognitive impairment (MCI) are an urgent public health priority. This study aimed to investigate the association of the Composite Dietary Antioxidant Index and alcohol consumption, as well as their interaction, with the risk of MCI. Methods: A multicenter cross-sectional study was conducted in 2020, involving 1084 individuals aged ≥55 years, in Zhejiang Province, China. Data were collected on demographics, cognitive function, alcohol consumption, depression scale, dietary intake and physical examinations. The Composite Dietary Antioxidant Index (CDAI) was calculated based on the converted Food Frequency Questionnaire (FFQ) Food Composition Tables and the data of the FFQ. CDAI values were divided into four groups by interquartile ranges: Quartile-1 (Q1), Quartile-2 (Q2), Quartile-3 (Q3) and Quartile-4 (Q4). Multivariate logistic regression models were used to evaluate the association of CDAI and alcohol consumption with MCI risk and their interaction. Results: The prevalence of MCI was 24.6%. After adjusting for gender, age, educational level, job, marriage, Body Mass Index (BMI), central obesity, frequency of social activities, depression, sleep disturbances, smoking, diabetes, and energy intake, the Q2 (OR = 0.63, 95% CI: 0.42~0.95), Q3 (OR = 0.52, 95% CI: 0.34~0.81) and Q4 (OR = 0.25, 95% CI: 0.14~0.48) of CDAI were significantly associated a reduced risk of MCI. In contrast, alcohol consumption 1~2 times per week (OR = 2.38, 95% CI: 1.02~5.59) and at least 3 times a month (OR = 2.04, 95% CI: 1.19~3.50) was significantly associated with an increased risk of MCI. Interaction analysis indicated a negative additive interaction between alcohol consumption and CDAI on MCI risk, with the detrimental effects of alcohol predominating. Conclusions: A higher CDAI is associated with a reduced risk of MCI, while alcohol consumption is associated with an increased risk. There may be a negative additive interaction between CDAI and alcohol intake in relation to MCI. Targeted strategies that reduce alcohol consumption and improve dietary antioxidant intake are essential for MCI prevention.