Association of change in brain structure to objectively measured physical activity and sedentary behavior in older adults:Age, Gene/Environment Susceptibility-Reykjavik Study

• Published in: Behavioural Brain Research
• Main Authors: Arnardóttir, Nanna Ýr, Koster, A, Van Domelen, Dane R, Brychta, Robert J, Caserotti, P., Eiriksdottir, Gudny, Sverrisdottir, Johanna Eyrun, Sigurdsson, SB, Jóhannsson, Erlingur, Chen, K. Y., Gudnason, V, Harris, T. B., Launer, L J, Sveinsson, Thórarinn
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2016
• Subjects: Physical activity Sedentary behavior Brain atrophy Elderly MRI white-matter integrity cognitive decline united-states tissue volumes aging humans risk-factors exercise health atrophy population Behavioral Sciences Neurosciences & Neurology; Sedentary behavior; Physical activity; MRI; Brain atrophy; Elderly; Disease Susceptibility; Follow-Up Studies; Humans; Atrophy/pathology; Male; Aging/pathology; Motor Activity/physiology; Gene-Environment Interaction; Gray Matter/pathology; Iceland; Magnetic Resonance Imaging; White Matter/pathology; Aged; 80 and over; Female
• Online Access: https://portal.findresearcher.sdu.dk/da/publications/529b9a82-c570-4974-a17b-562fe2c99b09; https://doi.org/10.1016/j.bbr.2015.09.005

Many studies have examined the hypothesis that greater participation in physical activity (PA) is associated with less brain atrophy. Here we examine, in a sub-sample (n = 352, mean age 79.1 years) of the Age, Gene/Environment Susceptibility-Reykjavik Study cohort, the association of the baseline and 5-year change in magnetic resonance imaging (MRI)-derived volumes of gray matter (GM) and white matter (WM) to active and sedentary behavior (SB) measured at the end of the 5-year period by a hip-worn accelerometer for seven consecutive days. More GM (β = 0.11; p = 0.044) and WM (β = 0.11; p = 0.030) at baseline was associated with more total physical activity (TPA). Also, when adjusting for baseline values, the 5-year change in GM (β = 0.14; p = 0.0037) and WM (β = 0.11; p = 0.030) was associated with TPA. The 5-year change in WM was associated with SB (β = -0.11; p = 0.0007). These data suggest that objectively measured PA and SB late in life are associated with current and prior cross-sectional measures of brain atrophy, and that change over time is associated with PA and SB in expected directions.