Physical Exercise Moderates the Relationship of Apolipoprotein E (APOE) Genotype and Dementia Risk: A Population-Based Study

Article type: Research Article

Authors: Fenesi, Barbara^a | Fang, Hanna^a | Kovacevic, Ana^a | Oremus, Mark^b | Raina, Parminder^{c; d; e} | Heisz, Jennifer J.^{a; d; e; *}

Affiliations: [a] Department of Kinesiology, McMaster University, Hamilton, ON, Canada | [b] School of Public Health and Health Systems, University of Waterloo, Waterloo, ON, Canada | [c] Health Research Methods, Evidence, and Impact (HE&I), McMaster University, Hamilton, ON, Canada | [d] McMaster Institute for Research on Aging, McMaster University, Hamilton, ON, Canada | [e] Labarge Centre for Mobility in Aging, McMaster University, Hamilton, ON, Canada

Correspondence: [*] Correspondence to: Jennifer J. Heisz, PhD, Department of Kinesiology, McMaster University, 1280 Main Street West, Hamilton, ON L8S 4K1, Canada. Tel.: +1 905 525 9140 x21944; Fax: +1 905 523 6011; E-mail: heiszjj@mcmaster.ca.

Abstract: Genetics and lifestyle independently determine dementia risk, but the interaction is unclear. We assessed the interactive relationship of apolipoprotein E (APOE) genotype and physical exercise on dementia risk over a 5-year period in 1,646 older adults from the Canadian Study of Health and Aging who were dementia-free at baseline. Physical exercise moderated the relationship between genotype and dementia (p < 0.01). Specifically, for APOE ɛ4 non-carriers, the odds of developing dementia were higher in non-exercisers than exercisers (OR = 1.98, 95% CI = 1.44, 2.71, p < 0.001), whereas, for APOE ɛ4 carriers, the odds of developing dementia were not significantly different between non-exercisers and exercisers (OR = 0.71, 95% CI = 0.46, 1.31, p = 0.34). Given that most individuals are not at genetic risk, physical exercise may be an effective strategy for preventing dementia.

Keywords: Alzheimer’s disease, apolipoprotein E4, dementia, exercise, physical activity, prevention

DOI: 10.3233/JAD-160424

Journal: Journal of Alzheimer's Disease, vol. 56, no. 1, pp. 297-303, 2017