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ARS Home » Northeast Area » Boston, Massachusetts » Jean Mayer Human Nutrition Research Center On Aging » Research » Publications at this Location » Publication #407508

Research Project: Longitudinal Analysis of Diet Quality, Health Outcomes and Mortality and Predictors of Living to Become a Centenarian

Location: Jean Mayer Human Nutrition Research Center On Aging

Title: Prospective study of diet quality and the risk of Dementia in the oldest old

item FLORES, ASHLEY - Pennsylvania State University
item JENSEN, GORDON - University Of Vermont College Of Medicine
item MITCHELL, DIANE - Pennsylvania State University
item NA, MUZI - Pennsylvania State University
item WOOD, G - Geisinger Medical Center
item STILL, CHRISTOPHER - Geisinger Medical Center
item GAO, XIANG - Fudan University

Submitted to: Nutrients
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/28/2023
Publication Date: 3/4/2023
Citation: Flores, A.C., Jensen, G.L., Mitchell, D.C., Na, M., Wood, G.C., Still, C.D., Gao, X. 2023. Prospective study of diet quality and the risk of Dementia in the oldest old. Nutrients. 15(5):1282.

Interpretive Summary: Problem Statement: Only a limited number of observational studies have examined the association between diet and risk of dementia with mixed results and have been primarily focused on populations not restricted to the oldest old. Research Accomplishment: In a prospective study of the oldest old conducted in over 2200 Geisinger Rural Aging Study participants, we observed that higher diet quality, as assessed by a validated diet quality screening tool, was not associated all-cause dementia or for subtypes of dementia (e.g., Alzheimer’s disease) within the first 4 years following diet quality screening suggesting that a healthy diet may not be protective against all-cause dementia or its subtypes. Research Contribution: The oldest old population remains an understudied age group, therefore, additional prospective studies with larger sample sizes, earlier baselines, longer follow-up durations, and better ascertainment of dementia and its subtypes are needed.

Technical Abstract: This study examined the associations between overall diet quality and the risk of dementia in a rural cohort among the oldest old. Included in this prospective cohort study were 2232 participants aged = 80 years and dementia-free at the baseline according to the Geisinger Rural Aging Study (GRAS), a longitudinal cohort in rural Pennsylvania. In 2009, diet quality was assessed by a validated dietary screening tool (DST). Incident cases of dementia during 2009–2021 were identified using diagnosis codes. This approach was validated by a review of electronic health records. Associations between diet quality scores and the incidence of dementia were estimated using the Cox proportional hazards models, adjusted for potential confounders. Across a mean of 6.90 years of follow-up, we identified 408 incident cases of all-cause dementia. Having a higher diet quality was not significantly associated with a lower risk for incidents of all-cause dementia (adjusted HR for the highest compared with the lowest tertile: 1.01, 95% CI: 0.79, 1.29, P-trend = 0.95). Similarly, we did not observe a significant association between diet quality and altered risks of Alzheimer’s disease and other forms of dementia. Overall, having a higher diet quality was not significantly associated with a lower risk of dementia among the oldest old during the full follow-up.