A1 Refereed original research article in a scientific journal
Body mass index and risk of dementia: Analysis of individual-level data from 1.3 million individuals.
Authors: Mika Kivimäki, Ritva Luukkonen, G. David Batty, Jane E. Ferrie, Jaana Pentti, Solja T. Nyberg, Martin J. Shipley, Lars Alfredsson, Eleonor I. Fransson, Marcel Goldberg, Anders Knutsson, Markku Koskenvuo, Eeva Kuosma, Maria Nordin, Sakari B. Suominen, Töres Theorell, Eero Vuoksimaa, Peter Westerholm, Hugo Westerlund, Marie Zins, Miia Kivipelto, Jussi Vahtera, Jaakko Kaprio, Archana Singh-Manoux, Markus Jokela
Publisher: Elsevier
Publication year: 2018
Journal: Alzheimer's and Dementia
Journal name in source: Alzheimer's & dementia : the journal of the Alzheimer's Association
Journal acronym: Alzheimers Dement
Volume: 14
Issue: 5
First page : 601
Last page: 609
Number of pages: 9
ISSN: 1552-5279
eISSN: 1552-5279
DOI: https://doi.org/10.1016/j.jalz.2017.09.016
We examined this hypothesis in 1,349,857 dementia-free participants from 39 cohort studies. BMI was assessed at baseline. Dementia was ascertained at follow-up using linkage to electronic health records (N = 6894). We assumed BMI is little affected by preclinical dementia when assessed decades before dementia onset and much affected when assessed nearer diagnosis.
Higher midlife body mass index (BMI) is suggested to increase the risk of dementia, but weight loss during the preclinical dementia phase may mask such effects.
The association between BMI and dementia is likely to be attributable to two different processes: a harmful effect of higher BMI, which is observable in long follow-up, and a reverse-causation effect that makes a higher BMI to appear protective when the follow-up is short.
Hazard ratios per 5-kg/m2 increase in BMI for dementia were 0.71 (95% confidence interval = 0.66-0.77), 0.94 (0.89-0.99), and 1.16 (1.05-1.27) when BMI was assessed 10 years, 10-20 years, and >20 years before dementia diagnosis.
