Shellfish-based dietary patterns and cognition in the Chinese senior population: A cross-sectional study in Qingdao, China.

Background and objectives: This study aims to investigate the association between dietary patterns and cognitive function among older adults with lower educational backgrounds living in China.

Methods and study design: We analyzed data from the 2018 Health Survey of individuals aged over 50 in Chengyang, Qingdao, China. Questionnaires were used to collect information on the behaviors and lifestyles of the elderly. The Montreal Cognitive Assessment (MoCA) was administered to evaluate cognition, with a total score of less than 19 indicating cognitive impairment for participants with low educational attainment. Using Principal Component Analysis, we identified three dietary patterns: Shellfish, Fruit, and Red Meat. Cross-sectional data regarding dietary intake, cognition, and demographics from 964 participants was analyzed using multivariate regression models to explore the relationship between dietary patterns and cognitive function.

Results: Our findings indicated that the 'Shellfish-based' dietary pattern ("Shellfish" DP) was significantly associated with cognitive function in both the third quartile (Q3: Odds Ratio = 0.58, 95% CI: 0.36-0.93, p <0.05) and the fourth quartile (Q4: OR = 0.54, 95% CI: 0.33-0.87, p <0.05). Furthermore, stratified analysis based on specific covariates revealed that significant results among individuals with a BMI of less than 25 kg/m² (OR = 0.57, 95% CI: 0.33-0.99, p <0.05). No significant interaction effects were observed between shellfish dietary intake and various subgroups (all interaction p >0.05).

Conclusions: Our research demonstrates that "Shell-fish" DP is negatively correlated with cognitive decline among the elderly population. This correlation is particularly significant in individuals with BMI < 25kg/m2, as well as among women and under the age of 65. However, no interaction was observed between the shellfish DP and the various subgroups. These findings can effectively guide older adults in optimizing their dietary structures, thereby safeguarding their cognition.