The relationships of self-efficacy, physical activity, and paid work to health-related quality of life among patients with chronic obstructive pulmonary disease (COPD)

PURPOSE Although chronic obstructive pulmonary disease (COPD) primarily affects the lungs, it is regarded as a systemic disorder associated with comorbidity and physical deterioration, which often results in reduced levels of health-related quality of life (HRQoL). Self-efficacy is an important concept in self-management, which is vital for improving HRQoL in patients with COPD. The purpose of this study was to examine how general self-efficacy, leisure time physical activity, and sociodemographic variables such as employment status are related to the physical and mental health components of HRQoL in patients with COPD. PATIENTS AND METHODS In this cross-sectional study, 97 COPD patients (54.6% male, mean age 64.6 years, standard deviation [SD] 9.5) beginning a pulmonary rehabilitation program completed three self-report questionnaires: the short form (SF)-12v2 Health Survey as a measure of HRQoL; the General Self-Efficacy Scale; and a standardized instrument measuring regular leisure time physical activity. RESULTS The physical health component median score was 31.3 (interquartile range [IQR] 16.3) and the mental health component median score was 45.9 (IQR 21.5). Two sets of linear regression analyses were performed, one predicting physical health and the other predicting mental health. The first analysis showed that better physical health was directly related to being in paid work (P-value <0.001), but was not significantly related to age, sex, marital status, education, work status, physical activity, or self-efficacy. In the second analysis, better mental health was directly related to living with a partner, being physically active, and having higher self-efficacy (P-value <0.001). CONCLUSION The findings suggest that general self-efficacy has differential relationships to the two dimensions of HRQoL. Our results indicate that general self-efficacy, physical activity, and paid work might be important factors for improving HRQoL of persons with COPD, and should be taken into consideration in pulmonary rehabilitation.