Mediterranean diet is associated with lower white matter lesion volume in Mediterranean cities and lower cerebrospinal fluid Aβ <subscript>42</subscript> in non-Mediterranean cities in the EPAD LCS cohort.

The Mediterranean diet (MedDiet) has been associated with better brain health and reduced incidence of dementia. Few studies have compared the effects of the MedDiet in early Alzheimer's disease or compared the effects of the diet within and outside of the Mediterranean region. The Mediterranean diet adherence screener (MEDAS) and MEDAS continuous scores were calculated at the baseline visit of the European Prevention of Alzheimer's Dementia Longitudinal Cohort Study (n = 1625). The scores were included in linear regression models to test for associations with hippocampal volume, log-transformed white matter lesion volume, cerebrospinal fluid pTau 18 , and Aβ 42 . Higher MEDAS scores were associated with lower log-transformed white matter lesion volume (β: -0.07, standard error [SE]: 0.02, p < 0.001). This association was only seen in the Mediterranean region (β: -0.12, SE: 0.03, p < 0.001). In the non-Mediterranean region, higher MEDAS continuous scores were associated with lower cerebrospinal fluid Aβ 42 (β: -68.30, SE: 14.32, p < 0.001). More research is needed to understand the differences in the associations seen with the MedDiet and Alzheimer's disease biomarkers in different European regions.

Competing Interests: Declaration of Competing Interest The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. KB has received consulting fees from Abcam, Axon, Biogen, JOMDD/Shimadzu, Julius Clinical, Lilly, MagQu, Novartis, Roche Diagnostics, and Siemens Healthineers and is the cofounder of Brain Biomarker Solutions (Gothenburg, Sweden). CWR has received consulting fees from Biogen, Eisai, MSD, Actinogen, Roche, and Eli Lilly, as well as receiving speaker fees from Roche and Eisai. CWR sits on an NIHR data safety monitoring board and is on an advisory board for Roche Diagnostics. CWR is an unpaid chair of the Brain Health Clinic Consortium (sponsored by Biogen), unpaid chair of the Scottish Dementia Research Consortium, and the director of Brain Health Scotland. SG, OS, ES, and GMT have no conflicts of interest to disclose.

(Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)