Trajectories of physical and mental health among persons with morbid obesity and persons with COPD: a longitudinal comparative study.

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. CONCLUSION 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.