title: Physical activity and depressive symptoms in older adults: 11-year follow-up.
abstract: BACKGROUND
  Few studies have explored the reciprocal relationships between naturally occurring changes in physical activity and depressive symptoms in later life.
  
  
  OBJECTIVE
  This study examined the reciprocal associations between changes in physical activity and depressive symptoms in a population-based sample of Taiwanese older adults over an 11-year period.
  
  
  METHODS
  Analyses were based on nationally representative data from the Taiwan's Health and Living Status of the Elderly Survey collected in 1996, 1999, 2003, and 2007. Data from the fixed cohort of 1160 participants aged ≥67 years in 1996 with 11 years of follow-up were studied. Depressive symptoms were assessed using the ten-item Chinese version of the Center for Epidemiologic Studies-Depression Scale. Physical activity was self-reported as the number of sessions per week. Latent growth modeling was used to examine the bidirectional associations between changes in physical activity and depressive symptoms when controlling for sociodemographic variables, lifestyle behaviors, and health status. Data analyses were completed in 2011.
  
  
  RESULTS
  With multivariate adjustment, initial levels of physical activity were negatively associated with changes in depressive symptoms (β=-0.34, p<0.05). In contrast, early depressive symptoms were not related to change in physical activity (β=-0.17, p>0.05).
  
  
  CONCLUSIONS
  Physical activity engagement in later life is associated with a lower risk of subsequent depressive symptoms, but the reverse association is not supported. The finding has underlying implications for future physical activity and mental health promotion in aged populations.
authors.affiliation: Graduate Institute of Sports and Health, National Changhua University of Education, Changhua City, Taiwan. powen.ku@gmail.com
authors.forename: Po-Wen
authors.initials: PW
authors.lastname: Ku
authors.forename: Kenneth R
authors.initials: KR
authors.lastname: Fox
authors.forename: Li-Jung
authors.initials: LJ
authors.lastname: Chen
authors.forename: Pesus
authors.initials: P
authors.lastname: Chou
mesh_terms: D000367:Age Factors; D000368:Aged; D003863:Depression / Q000453:epidemiology*; D005260:Female; D005500:Follow-Up Studies; D006293:Health Promotion / Q000379:methods; D006304:Health Status; D006306:Health Surveys; D006801:Humans; D008019:Life Style; D008137:Longitudinal Studies; D008297:Male; D009043:Motor Activity; D015999:Multivariate Analysis; D011446:Prospective Studies; D013624:Taiwan / Q000453:epidemiology