Background: Sleep disturbance has been termed the forgotten dimension of chronic obstructive pulmonary disease (COPD), but it is clinically important as most patients are affected. This study examined the incremental burden of illness associated with sleep disturbance in COPD, with reference to health status and disease impact, and the degree of concordance between physicians and patients in reporting night-time COPD symptoms.
Methods: Real-world data from >2,500 patients with COPD consulting for routine care were derived from respiratory Disease-Specific Programs conducted in Europe, the USA, and China. Night-time COPD symptom burden was assessed from patient and physician perspectives. Patients completed the Jenkins Sleep Evaluation Questionnaire (JSEQ), COPD assessment test (CAT), and EuroQol five-dimension questionnaire (EQ-5D). A regression approach was used to analyze the relationship between sleep disturbance (JSEQ score) and health status (EQ-5D score), adjusting for confounding variables.
Results: Frequency of night-time symptoms was high and was higher when reported by patients than physicians (69.7% and 65.7%, respectively). According to the JSEQ, 73.3% of patients had trouble falling asleep, 75.3% experienced night-time awakenings, 70.6% had trouble staying asleep, and 67.7% woke after a usual amount of sleep feeling worn out. Over half (52.7%) of patients received maintenance treatment where night-time symptom relief was stated by the physician as a treatment aim. A one unit increase in JSEQ score was associated with increased CAT score (0.7 units in Europe and the USA; 0.2 units in China). Sleep disturbance was significantly associated with worse health status (odds ratio [OR]: 1.27, 95% confidence interval [CI]: 1.18, 1.36, P<0.001 for Europe; OR: 1.23, 95% CI: 1.12, 1.38, P<0.001 for the USA; and OR: 1.19, 95% CI: 1.10, 1.28, P<0.001 for China).
Conclusions: Night-time symptoms and sleep disturbance are common among patients with COPD, and sleep disturbance has a detrimental impact on COPD symptoms and health status.
Keywords: COPD; health status; night-time symptom; sleep disturbance.