title: A longitudinal community study of major depression and physical activity.
abstract: BACKGROUND
  The objective of this study was to determine whether major depressive episodes (MDEs) are associated transitions between active and inactive recreational activity patterns.
  
  
  METHODS
  The data source was the Canadian National Population Health Survey (NPHS). The NPHS included a brief instrument to assess MDEs and collected data on participation in recreational activities. In order to meaningfully categorize participation in recreational activities, the participation data was translated into overall estimated metabolic energy expenditure. A threshold of 1.5 kcal/kg per day was used to distinguish between active and inactive activity patterns. Proportional hazards models were used to compare the incidence of inactivity in initially active respondents with and without MDE and to compare the frequency of becoming active among initially inactive respondents with and without MDE.
  
  
  RESULTS
  For active respondents with MDE, an elevated risk of transition into an inactive pattern was observed [adjusted hazard ratio (HR)=1.6; 95% CI 1.2-1.9]. However, MDE did not affect the probability of moving from an inactive to an active lifestyle (adjusted HR=1.0; 95% CI 0.78-1.19).
  
  
  CONCLUSIONS
  Major depressive episodes are associated with an increased risk of transition from an active to an inactive pattern of activity.
authors.affiliation: Department of Community Health Sciences, University of Calgary, Calgary T2N 4N1, Canada. patten@ucalgary.ca
authors.forename: Scott B
authors.initials: SB
authors.lastname: Patten
authors.forename: Jeanne V A
authors.initials: JV
authors.lastname: Williams
authors.forename: Dina H
authors.initials: DH
authors.lastname: Lavorato
authors.forename: Michael
authors.initials: M
authors.lastname: Eliasziw
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D002170:Canada; D002648:Child; D003865:Major Depressive Disorder / Q000453:epidemiology* / Q000523:psychology; D005260:Female; D015438:Health Behavior; D006306:Health Surveys; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009043:Motor Activity; D016016:Proportional Hazards Models; D011998:Recreation / Q000523:psychology; D057185:Sedentary Behavior; D012737:Sex Factors; D055815:Young Adult