Correlation between disease severity factors and EQ-5D utilities in chronic obstructive pulmonary disease

Abstract

Purpose: Impaired health-related quality of life (HRQoL) is associated with poor health outcomes in chronic obstructive pulmonary disease (COPD). The aim of this study was to determine health utilities in patients with COPD and to identify the variables with the greatest impact.

Methods: This is a pooled analysis of data from 4 observational studies performed in stable COPD patients. Evaluation of patient HRQoL utilities was performed using the Spanish version of the self-administered EuroQoL 5 Dimensions (EQ-5D) questionnaire. EQ-5D utilities were described and compared according to several markers of disease severity.

Results: 6198 patients reported a mean (SD) EQ-5D index of 0.67 (0.26). A linear dose response relationship between EQ-5D utility and modified Medical Research Council (mMRC) score, forced expiratory volume in one 1 s (% predicted), COPD hospital admissions in the previous year, self-reported daily walking time, Charlson index, body mass index, obstruction, dyspnoea and exacerbation (BODEx) index, COPD assessment test (CAT), hospital anxiety and depression scale was observed (p for trend < 0.001). In multivariate analysis, patients reporting lower utility values were those with more dyspnoea, more comorbidities, using long-term oxygen therapy, with previous hospitalisations due to a COPD exacerbation and higher (worse) CAT score.

Conclusion: HRQoL measures such as EQ-5D can assist clinicians to understand the impact of respiratory disease on COPD patients.

Keywords: CAT; COPD; EQ-5D; Health-Related Quality of Life.