Association between dietary inflammatory index score and incident dementia

Introduction: We evaluated whether higher Dietary Inflammatory Index (DII) scores were associated with increased incidence of all-cause dementia and Alzheimer's disease (AD) dementia over 22.3 years of follow-up in the community-based Framingham Heart Study Offspring cohort.

Methods: One thousand four hundred eighty-seven participants (mean ± standard deviation, age in years 69 ± 6) completed food frequency questionnaires (FFQs) and had incident all-cause dementia and AD surveillance data available.

Results: Two hundred forty-six participants developed all-cause dementia (including AD, n = 187) over a median follow-up time of 13.1 years. Higher DII scores, averaged across a maximum of three timepoints, were associated with an increased incidence of all-cause dementia and AD after adjustment for demographic, lifestyle, and clinical covariates (hazard ratio [HR] 1.21, 95% confidence interval [CI] 1.10-1.33, P < 0.001; HR 1.20, 95% CI: 1.07-1.34d, P = 0.001, respectively).

Discussion: Higher DII scores were associated with a higher risk of incident all-cause dementia and AD. Although these promising findings need to be replicated and further validated, our results suggest that diets that correlate with low DII scores may prevent late-life dementia.

Highlights: Higher Dietary Inflammatory Index (DII) scores were associated with an increased incidence of all-cause dementia. Higher DII scores were associated with an increased incidence of Alzheimer's disease dementia. Diets that correlate with low DII scores may prevent late-life dementia.