Lung hyperinflation is related to poor sleep quality in patients with COPD

Background: Poor sleep quality as assessed by overnight polysomnography (i.e., low sleep efficiency and/or low % rapid-eye movement (REM) sleep) is frequently reported in COPD. More symptomatic patients tend to present with worst sleep quality ( Scharf et al. Int J Chron Obstruct Pulmon Dis. 2010;6:1–12 ). Considering the close association between symptom burden and lung hyperinflation in COPD ( O9Donnell DE et al. Expert Rev Respir Med. 2016;10:823-34 ), we hypothesized that hyperinflation would be negatively related to sleep quality in these patients. Methods: We retrospectively assessed 182 patients (FEV 1 =69±20% predicted, GOLD stages I to IV) who performed spirometry, body plethysmography and overnight polysomnography. Results: Sleep efficiency (68±16%) and % REM (14±8%) were reduced compared to historical controls. In a multiple regression analysis, inspiratory capacity/total lung capacity (IC/TLC) ratio, apnea-hypopnea index (AHI) and sleep SpO 2 nadir - but not FEV 1 or body mass index - remained as independent predictors of poor sleep efficiency ( p 2 p 1 (% predicted) than their counterparts with better sleep quality (0.40±0.09 vs 0.44±0.09; p Conclusion: Lung hyperinflation is associated with poor sleep quality regardless the severity of airflow obstruction in patients with COPD. Decreasing overnight lung volumes might prove therapeutically useful to improve sleep quality in these patients.