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.
ISI Document Delivery No.: CY0EL Times Cited: 2 Cited Reference Count: 66 Arnardottir, Nanna Yr Koster, Annemarie Van Domelen, Dane R. Brychta, Robert J. Caserotti, Paolo Eiriksdottir, Gudny Sverrisdottir, Johanna E. Sigurdsson, Sigurdur Johannsson, Erlingur Chen, Kong Y. Gudnason, Vilmundur Harris, Tamara B. Launer, Lenore J. Sveinsson, Thorarinn Koster, Annemarie/E-7438-2010; Chen, Kong/0000-0002-0306-1904 NIA [N01-AG-1-2100]; NIA Intramural Research Program, Hjartavernd (the Icelandic Heart Association); Althingi (the Icelandic Parliament); National Science Foundation Graduate Research Fellowship [DGE-0940903]; National Institutes of Health Intramural Research Program [Z01 DK071013, Z01 DK071014] This study has been funded by NIA contract N01-AG-1-2100, the NIA Intramural Research Program, Hjartavernd (the Icelandic Heart Association), and the Althingi (the Icelandic Parliament). This work was also supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-0940903 and by the National Institutes of Health Intramural Research Program, grant number: Z01 DK071013 and Z01 DK071014 to RJB and KYC. Thor Aspelund is acknowledged for statistical consultation. The researchers are indebted to the participants for their willingness to participate in the study. 2 18 Elsevier science bv Amsterdam 1872-7549