Sleep disturbance in patients with mild-moderate chronic obstructive pulmonary disease

Although sleep problems have an important impact on daily life and health outcome measures in patients with chronic obstructive pulmonary disease (COPD), patterns of sleep disturbance in patients with mild-moderate COPD remain unknown.

The aim of this study was to investigate patterns of sleep disturbance and factors associated with sleep impairment in patients with mild-moderate COPD.

This prospective cross-sectional study enrolled 148 male patients with COPD. At enrolment, all patients completed a disease-specific sleep measure, the COPD and Asthma Sleep Impact Scale (CASIS) to assess sleep impairment. Health-related quality of life (HRQL) was measured using the St. George's Respiratory Questionnaire (SGRQ) and the 36-item Short-Form health survey (SF-36). Anxiety and depression status were assessed using the Hospital Anxiety and Depression Scale (HADS). Self-efficacy was measured by the COPD Self-Efficacy Scale (CSES).

The mean age of the subjects was 67 years [standard deviation (SD) = 8.11]. The proportion of patients who indicated that they had a bad night's sleep was 33.1%. Univariated analysis showed that CASIS score was significantly correlated with the modified Medical Research Council (mMRC) dyspnea scale, SGRQ, SF-36 Physical Component Summary, SF-36 Mental Component Summary, HADS-anxiety, HADS-depression and CSES scores (all P < 0.05). In a multivariate analysis, SGRQ and CSES were independently associated with CASIS score.

Poorer HRQL and lower self-efficacy are significantly associated with sleep disturbance and perhaps may be improved by better sleep quality. Future research is required to enhance sleep quality in patients with mild-moderate COPD.