The interaction between sugar-sweetened beverage consumption and emotional status with subjective cognitive decline among rural older adults: a cross-sectional study.

OBJECTIVES: This study explored the interactive and joint effects of Sugar-Sweetened Beverage (SSB) consumption, positive and negative affect with Subjective Cognitive Decline (SCD) among rural older adults, providing empirical evidence for formulating targeted strategies for the early intervention of cognitive decline in the rural older population. METHODS: This cross-sectional study recruited 485 valid participants from rural areas of Ningxia, China, using a stratified cluster sampling method. Key indicators were assessed with the subjective cognitive decline questionnaire, the positive and negative affect schedule, the sugar-sweetened beverage consumption questionnaire, and sociodemographic covariates. Data analysis included independent-samples t-test, analysis of variance, correlation analysis, and linear regression models with the PROCESS macro in SPSS for examining interaction effects. RESULTS: Gender, education, and self-rated health were independent associated factors of SCD among rural older adults. Positive affect was negatively correlated with SCD (β = -0.238, P < 0.001), while negative affect was positively correlated with SCD (β = 0.377, P < 0.042). There was an interactive effect between SSB consumption and positive affect on SCD (β = 0.082, P = 0.012). Simple slope analysis showed that higher positive affect was associated with less severe SCD among no SSB consumers, whereas the protective effect of positive affect against SCD was significantly attenuated among SSB consumers. The joint effect analysis revealed that compared with the reference group (no SSB consumption + high positive affect/no SSB consumption + high negative affect): Participants in the no SSB consumption + low positive affect group had significantly higher SCD scores (β = 0.959, P < 0.001). Participants in the no SSB consumption + low negative affect group had significantly lower SCD scores (β = -0.778, P = 0.003). The SSB consumption + low negative affect group had the lowest SCD scores, with a highly significant reduction compared with the reference group (β = -0.936, P < 0.001). CONCLUSION: The inverse association of positive affect with SCD was significantly weakened among participants with SSB consumption. Regardless of SSB consumption, low negative affect corresponded to milder SCD, suggesting possible directions that require prospective confirmation.