Lee SH, et al. - Via a prospective cross-sectional study that recruited 148 male patients with COPD, researchers examined patterns of sleep disturbance and factors related to sleep impairment in patients with mild-moderate COPD. The mean age of the patients was 67 years. The proportion of patients who showed that they had a bad night's sleep was 33.1%. The univariate analysis exhibited that COPD and Asthma Sleep Impact Scale (CASIS) score was significantly associated with the modified Medical Research Council dyspnea scale, St. George's Respiratory Questionnaire (SGRQ), Short-Form health survey (SF-36) Physical Component Summary, SF-36 Mental Component Summary, Hospital Anxiety and Depression Scale (HADS)-anxiety, HADS-depression and COPD self-efficacy scale (CSES) scores. In a multivariate analysis, SGRQ and CSES were independently related to CASIS score. Therefore, poorer health-related quality of life and lower self-efficiency are significantly related to sleep disturbance, and perhaps maybe enhanced by better sleep quality.