2026-06-26 カロリンスカ研究所（KI）
＜関連情報＞
- https://news.ki.se/healthier-diet-linked-to-lower-dementia-in-older-adults-at-risk
- https://jamanetwork.com/journals/jamanetworkopen/fullarticle/2850780
アルツハイマー病理を有する高齢者における食事の質と認知症リスク Diet Quality and Dementia Risk in Older Adults With Alzheimer Pathology
Anja Mrhar, MSc; Adrián Carballo-Casla, PhD; Giulia Grande, MD, PhD;et al
JAMA Network Open June 25, 2026
DOI:10.1001/jamanetworkopen.2026.20254
Key Points
Question Is higher diet quality associated with lower dementia risk among older adults with Alzheimer disease pathology or broader neurodegenerative and glial processes?
Findings In this cohort study of 1865 older adults without dementia followed up for up to 15 years, higher diet quality was associated with lower dementia risk. Among participants at higher risk, only a dietary pattern with lower inflammatory potential showed consistent inverse associations.
Meaning These findings reinforce the importance of targeted dietary dementia prevention strategies for the general population and individuals already at elevated risk.
Abstract
Importance Higher diet quality has been linked to reduced dementia incidence, but whether it buffers dementia onset in individuals with Alzheimer disease (AD) pathology or broader neurobiological risk is unclear.
Objective To explore the association of diet quality with dementia risk across biomarker levels of AD pathology (phosphorylated tau at threonine 217 [p-tau217]) and broader neurodegenerative and glial processes (neurofilament light chain [NFL], glial fibrillary acidic protein [GFAP]).
Design, Setting, and Participants This cohort study analyzed data from adults without dementia aged 60 years or older from the population-based Swedish National Study on Aging and Care in Kungsholmen, which enrolled participants between March 2001 and August 2004 and examined them up to 6 times until February 2016 to November 2019. Adherence to 3 dietary patterns was examined: the Alternate Mediterranean Diet (AMED), Alternative Healthy Eating Index (AHEI), and reversed Empirical Dietary Inflammatory Index (rEDII). Data were analyzed between September 2024 and August 2025 and reanalyzed in March and April 2026.
Exposures Baseline serum p-tau217, NFL, and GFAP concentrations and repeated adherence over 6 years to the AMED, AHEI, and rEDII dietary patterns.
Main Outcomes and Measures The primary outcome was all-cause dementia identified by clinical diagnosis, medical records, and death certificates. The secondary outcome was AD-related dementia. Dementia risk was analyzed using adjusted Cox regression models. Ten-year dementia probabilities and restricted mean time lost due to dementia were also estimated.
Results A total of 1865 participants were included (mean [SD] age at baseline, 70.5 [9.3] years; 1125 female [60.3%]). Over a mean follow-up of 8.4 years (range, <0.1 to 15.9 years), 240 participants developed dementia. Higher adherence to healthier dietary patterns was associated with lower dementia risk in participants with elevated AD and neurobiological risk biomarkers. For rEDII, each 1–z-score increase in adherence was associated with lower dementia risk among those with elevated p-tau217, NFL, and GFAP levels, with hazard ratios of 0.71 (95% CI, 0.58-0.88), 0.79 (95% CI, 0.66-0.95), and 0.73 (95% CI, 0.60-0.89), respectively. Associations of AMED and AHEI with lower dementia risk were generally found only among participants with lower biomarker levels. Similar findings were observed for AD-related dementia.
Conclusions and Relevance This cohort study of older adults found that adherence to a dietary pattern with lower inflammatory potential was associated with lower dementia risk among individuals with AD pathology and broader neurobiological risk. These findings reinforce the importance of targeted dietary dementia prevention strategies not only for the general population but also for individuals already at elevated risk.
