RESUMO
Background: To assess the health-related quality of life (HRQoL) of Taiwan patients with different stages of chronic obstructive pulmonary disease (COPD) and using different combination therapies and to explore the factors affecting HRQoL in these patients. Methods: This cross-sectional study included outpatient participants aged 35 years old and older who were receiving long-acting bronchodilator treatment in one of two hospitals in Southern Taiwan. Participants were categorized according to their Global Initiative for Obstructive Lung Disease (GOLD) classification as either their COPD group, based on symptoms and exacerbation risk, or their COPD stage, based on spirometry results. Patients' HRQoL was assessed using the St. George's Respiratory Questionnaire score (SGRQ), World Health Organization Quality of Life Quality of Life-BREF (WHOQOL-BREF), and EQ-5D-5L. The total scores of the SGRQ, WHOQOL-BREF, EQ-5D utility index, and EQ-VAS were presented as mean ± standard deviation (SD) among different combination treatments. Univariate and multivariate analyses were used to explore the association of patients' baseline characteristics and environmental factors with HRQoL. Results: A total of 218 patients were enrolled in the study. The distribution of patients using GOLD group classification were as follows: 73.39% in group A, 20.19% group B, 1.83% group C and 4.59% group D. Triple therapy patients mostly showed a lower quality of life than other combination therapies, regardless of the GOLD classification system. However, only the SGRQ scores of GOLD groups A and B were significantly different when using different drug combinations (p-value = 0.0072 and 0.0430, respectively). The COPD assessment test (CAT) score, a questionnaire to assess impact of COPD on health status, was found to be associated with all the questionnaires. Conclusion: The HRQoL is impaired in patients with COPD, and it deteriorates with an increase of severity. The CAT was the strongest predictor of HRQoL.