Dietary Patterns and Cognitive Dysfunction in a 12-Year Follow-up Study of 70 Year Old Men

Background: Adherence to dietary patterns has been associated with cognitive decline and dementia, but studies are inconsistent. Objective: Dietary patterns, i.e., WHO recommendations (Healthy Diet Indicator), a Mediterranean-like diet (modified Mediterranean Diet Score, mMDS), and a low carbohydrate high protein diet (LCHP), were related to incident cognitive dysfunction, as indicated by Alzheimer's disease (AD), all-type dementia, and all-type cognitive impairment, in a cohort of 1,138 elderly Swedish men. Methods: Dietary patterns were derived from 7-day records. Risk relations were calculated by Cox and logistic regression analyses, adjusted for potential confounders. Sensitivity analysis was performed in a subpopulation (n = 564) with energy intake according to the Goldberg cut-off. Results: During a mean follow-up of 12 years, 84, 143, and 198 men developed AD, all-type dementia, and all-type cognitive impairment, respectively. There was no association between Healthy Diet Indicator and any of the outcomes. Hazard ratios associated with 1 standard deviation (SD) increment in the LCHP score were 1.16 (95% confidence interval [CI]: 0.95, 1.43) for AD and 1.16 (95% CI: 0.99, 1.37) for all-type dementia. mMDS was not associated with dementia diagnosis. Odds ratio (OR)/1 SD increase for mMDS and all-type cognitive impairment was 0.82 (95% CI: 0.65, 1.05). In the subpopulation OR for mMDS and all-type cognitive impairment was 0.32 (95% CI: 0.11, 0.89). Conclusion: We found no strong associations with development of cognitive dysfunction for any of the dietary patterns investigated. However, there was a potentially beneficial association for a Mediterranean-like diet on the development of cognitive dysfunction in the subpopulation.