Self-Reported Physical Activity is Associated with Tau Burden Measured by Positron Emission Tomography

Article type: Research Article

Authors: Brown, Belinda M.^{a; b; *} | Rainey-Smith, Stephanie R.^{b; c} | Dore, Vincent^d | Peiffer, Jeremiah J.^a | Burnham, Samantha C.^e | Laws, Simon M.^{b; c; f; g; h} | Taddei, Kevin^{b; c} | Ames, David^{i; j} | Masters, Colin L.^k | Rowe, Christopher C.^l | Martins, Ralph N.^{b; c; m} | Villemagne, Victor L.^l

Affiliations: [a] School of Psychology and Exercise Science, Murdoch University, Murdoch, WA, Australia | [b] Sir James McCusker Alzheimer’s Disease Research Unit, Hollywood Private Hospital, Nedlands, WA, Australia | [c] School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia | [d] eHealth, CSIRO Health and Biosecurity, Herston, QLD, Australia | [e] eHealth, CSIRO Health and Biosecurity, Parkville, VIC, Australia | [f] Collaborative Genomics Group, School of Medical and Health Sciences, Edith Cowan University, Joondalup, WA, Australia | [g] School of Biomedical Sciences, Faculty of Health Sciences, Curtin Health Innovation Research Institute, Curtin University, WA, Australia | [h] Cooperative Research Centre for Mental Health, http://www.mentalhealthcrc.com | [i] Department of Psychiatry, University of Melbourne, VIC, Australia | [j] National Ageing Research Institute, Parkville, VIC, Australia | [k] Florey Institute for Neurosciences and Mental Health, University of Melbourne, VIC, Australia | [l] Department of Nuclear Medicine and Centre for PET, Austin Health, Heidelberg, VIC, Australia | [m] Department of Biomedical Sciences, Macquarie University, Sydney, NSW, Australia

Correspondence: [*] Correspondence to: Belinda M. Brown, PhD, School of Psychology and Exercise Science, Murdoch University, 90 South Street, Murdoch, 6157 WA, Australia. Tel.: +61 8 9360 6193; E-mail: b.brown@murdoch.edu.au.

Abstract: Numerous animal studies have reported exercise reduces the accumulation of Alzheimer’s disease pathology, including amyloid-β (Aβ) and tau. Furthermore, we previously reported a relationship between higher levels of physical activity (PA) and lower brain Aβ burden in a human population. The recent advent of tau positron emission tomography (PET) tracers enables us to extend our investigations into the evaluation of the relationship between PA and brain tau burden. Utilizing data from the Australian Imaging, Biomarkers and Lifestyle (AIBL) study, we have examined the cross-sectional relationship between habitual PA and PET-quantified tau burden. Forty-three cognitively healthy older adults were categorized into low-moderate PA (LMPA; n = 16) or high PA (HPA; n = 27), based on self-reported PA levels. Tau PET imaging with the AV1451 tracer was conducted on all participants. The LMPA group had significantly higher neocortical tau burden (presented as a z-score; 1.22±1.98), compared to the HPA group (z-score: – 0.28±1.18). The difference between the LMPA and HPA groups was also evident when examining regional tau burden in the temporoparietal cortex and the prefrontal cortex. Our results suggest an association between self-reported PA level and brain tau burden. Future longitudinal and interventional studies utilizing larger samples sizes are vital to further investigate the nature of the relationship between tau and PA.

Keywords: Alzheimer’s disease, physical activity, positron emission tomography, tau

DOI: 10.3233/JAD-170998

Journal: Journal of Alzheimer's Disease, vol. 63, no. 4, pp. 1299-1305, 2018