Does a self-management education program have the same impact on emotional and functional dimensions of HRQoL?

Most previous research evaluating the effect of interventions on HRQoL in COPD patients has focused on measuring HRQoL using aggregated questionnaire scores, increasing the risk of false-negative results. There is also evidence to suggest that self-evaluations of functional status are less likely to be modified over time relative to self-evaluation of emotional status. This study was a secondary analysis of a prospective study that compared the efficacy of a self-management education program (SM) on emotional and functional dimensions of HRQoL. One hundred and ten patients were recruited from the Sacré-Coeur Hospital of Montreal (Canada). Patients were included in either the SM group (n = 60) or the usual-care group (UC, n = 50). The SM group underwent a 4-week intervention based on content featured in "Living Well with COPD" program. Patients were assessed pre and 12-months post-intervention; the primary outcome was net change in the emotional and functional subscales scores of the St-George's Respiratory Questionnaire (SGRQ) and Short-Form health survey questionnaire (SF-36). Only the emotional dimension scores of both the SGRQ (impact) and the SF-36 (mental component summary) were statistically and clinically improved in the SM group compared to UC. Also, the 12-month adjusted between-group difference in the SGRQ-impact scores was 3-fold higher than the minimum clinically important difference in SM vs. UC patients. HRQoL needs to be regarded as a combination of distinct self-evaluations with unique dynamics over time. This distinction should be taken into account in program development and evaluation, to choose intervention components likely to impact on both types of self-evaluations related to HRQoL.