Aakre, Jeremiah A.

AbstractIntroductionThe Mediterranean diet (MeDi) is associated with reduced risk of cognitive impairment, but it is unclear whether it is associated with better brain imaging biomarkers.MethodsAmong 672 cognitively normal participants (mean age, 79.8 years, 52.5% men), we investigated associations of MeDi score and MeDi components with magnetic resonance imaging measures of cortical thickness for the four lobes separately and averaged (average lobar).ResultsHigher MeDi score was associated with larger frontal, parietal, occipital, and average lobar cortical thickness. Higher legume and fish intakes were associated with larger cortical thickness: legumes with larger superior parietal, inferior parietal, precuneus, parietal, occipital, lingual, and fish with larger precuneus, superior parietal, posterior cingulate, parietal, and inferior parietal. Higher carbohydrate and sugar intakes were associated with lower entorhinal cortical thickness.DiscussionIn this sample of elderly persons, higher adherence to MeDi was associated with larger cortical thickness. These cross‐sectional findings require validation in prospective studies.

Objectives To determine the association between multiple chronic conditions and risk of incident mild cognitive impairment ( MCI ) and dementia. Design Prospective cohort study. Setting Olmsted County, Minnesota. Participants Cognitively normal individuals (N = 2,176) enrolled in the Mayo Clinic Study of Aging ( MCSA ). Measurements Participants were randomly selected from the community, evaluated by a physician, and underwent neuropsychometric testing at baseline and at 15‐month intervals to assess diagnoses of MCI and dementia. Information on International Classification of Diseases, Ninth Revision codes for chronic conditions in the 5 years before enrollment was electronically captured using the Rochester Epidemiology Project medical records linkage system. Multimorbidity was defined as having two or more chronic conditions, and the association between multimorbidity and MCI and dementia was examined using Cox proportional hazards models. Results Of 2,176 cognitively normal participants (mean age ± standard deviation 78.5 ± 5.2; 50.6% male), 1,884 (86.6%) had multimorbidity. The risk of MCI or dementia was higher in persons with multimorbidity (hazard ratio ( HR ) = 1.38, 95% confidence interval ( CI ) = 1.05–1.82) than in those with one or no chronic condition. The HR was of greater magnitude in persons with four or more conditions ( HR = 1.61, 95% CI = 1.21–2.13) than in those with two or three conditions ( HR = 1.03, 95% CI = 0.76–1.39) and for men with multimorbidity( HR = 1.53, 95% CI = 1.01–2.31) than for women with multimorbidity ( HR = 1.20, 95% CI = 0.83–1.74), compared to those with one or no chronic condition. Conclusion In older adults, having multiple chronic conditions is associated with greater risk of MCI and dementia. This is consistent with the hypothesis that multiple etiologies may contribute to MCI and late‐life dementia. Preventing chronic diseases may be beneficial in delaying or preventing MCI and dementia.