title: Trajectories of physical and mental health among persons with morbid obesity and persons with COPD: a longitudinal comparative study.
abstract: BACKGROUND
  Morbid obesity and chronic obstructive pulmonary disease (COPD) are prevalent diseases associated with impaired health-related quality of life (HRQoL). Research generally indicates that persons with morbid obesity increase their HRQoL following intervention, whereas evidence of increases in HRQoL in persons with COPD is mixed. Examining the patterns of change over time instead of merely examining whether HRQoL changes will add to the knowledge in this field.
  
  
  METHODS
  A sample of persons with morbid obesity and persons with COPD was recruited from learning and mastery courses and rehabilitation centers in Norway. The data were collected by self-report questionnaires at the start of patient education and at four subsequent time points during the 1-year follow-up. HRQoL was measured with the Short Form 12, version 2, and repeated measures analysis of variance was employed in the statistical analysis.
  
  
  RESULTS
  Participants with morbid obesity linearly increased their physical HRQoL during the 1-year follow-up, whereas participants with COPD showed no change. None of the groups changed their mental HRQoL during follow-up. In all subdomains of HRQoL, the participants with morbid obesity showed favorable, linearly increasing trajectories across the follow-up period. Among the participants with COPD, no change patterns occurred in the subdomains of HRQoL, except for a fluctuating pattern in the mental health domain. Age, sex, and work status did not influence the trajectories of HRQoL in any of the domains.
  
  
  CONCLUSIONS
  A more favorable trajectory of HRQoL was found for persons with morbid obesity than for persons with COPD, possibly due to the obese persons' better chances of recovery.
authors.affiliation: Department of Occupational Therapy, Prosthetics and Orthotics, Faculty of Health Sciences, Oslo and Akershus University College of Applied Sciences, Oslo, Norway.
authors.forename: Tore
authors.initials: T
authors.lastname: Bonsaksen
authors.affiliation: Department of Nursing Science, Institute of Health and Society, Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: May Solveig
authors.initials: MS
authors.lastname: Fagermoen
authors.affiliation: Department of Nursing Science, Institute of Health and Society, Faculty of Medicine, University of Oslo, Oslo, Norway; Department for Patient Safety and Development, Lovisenberg Diakonale Hospital, Oslo, Norway.
authors.forename: Anners
authors.initials: A
authors.lastname: Lerdal
keywords: SF 12; change patterns; health-related quality of life; longitudinal study; patient education course