Scientific investigations

Study Objectives: The aim of this study was to compare the risk of undiagnosed sleep disorders among medical patients with chronic obstructive pulmonary disease (COPD) compared with those without COPD. Methods: In a prospective cohort study, hospitalized medical ward patients without a known sleep disorder were screened, using validated questionnaires, for sleep disorders, such as obstructive sleep apnea and insomnia. Daily sleep duration and efficiency in the hospital were measured via wrist actigraphy. Participants were classified into two groups: those with a primary or secondary diagnosis of COPD and those without a history of COPD diagnosis. Sleep outcomes were compared by COPD diagnosis. Results: From March 2010 to July 2015, 572 patients completed questionnaires and underwent wrist actigraphy. On admission, patients with COPD had a greater adjusted risk of obstructive sleep apnea (adjusted odds ratio 1.82, 95% confidence interval 1.12–2.96, P =.015) and clinically significant insomnia (adjusted odds ratio 2.07, 95% confidence interval 1.12–3.83, P =.021); no differences were observed for sleep quality or excess sleepiness on admission. After adjustment, compared with patients without COPD, patients with COPD averaged 34 fewer minutes of nightly sleep (95% confidence interval 4.2–64.0 minutes, P =.026), as well as 22.5% lower odds of normal sleep efficiency while in the hospital (95% confidence interval 3.3%–37.9%, P =.024). No statistically significant differences were observed for in-hospital sleep quality, soundness, or ease of falling asleep. Conclusions: Among hospitalized patients in medical wards, those with COPD have higher risk of OSA and insomnia and worse in-hospital sleep quality and quantity compared with those without COPD.