0899 Determinants of Sleep Quality in Patients with Chronic Obstructive Pulmonary Disease and Concomitant Obstructive Sleep Apnea: the COPD-OSA Overlap Syndrome

Abstract

Introduction: In chronic obstructive pulmonary disease (COPD) patients without associated obstructive sleep apnea (OSA) quantitative measurements of sleep quality appear to be related to the severity of obstructive airways disease and nocturnal oxygenation. However, the determinants of sleep quality in patients with COPD-OSA overlap syndrome are unknown. We hypothesize that both parameters of airflow obstruction and severity of OSA contribute to the sleep quality in COPD-OSA overlap syndrome. Method(s): Participants were derived from the COPDGene project. The study included patients who underwent a full night polysomnogram (PSG) and where diagnosed with OSA (AHI>= 5 events/hr). To confirm the presence of COPD, and prior to the PSG, patients had spirometry performed, and obtained a chest computed tomography (CT) for measurements of percent emphysema and gas trapping. Result(s): Twenty-one patients [10 (48%) males, 57 +/- 8 years/old, FEV1 1.2 +/- 0.5 L, FEV1 %Predicted 45 +/- 19%, FVC 2.3 +/- 0.7 L, FVC %Predicted 68 +/- 20%, FEV1/FVC 50 +/- 11%, BMI 34 +/- 9 kg/ m2)] were diagnosed with OSA (apnea-hypopnea index [AHI] 16 +/- 12 events/hour). The total sleep time (TST) was 286 +/- 86 minutes with a sleep efficiency (SE) of 67 +/- 23%. The Arousal index (AI) was 26 +/- 27 arousals/hr. The mean SaO2 was 93 +/- 3% with the lowest SaO2 of 82 +/- 7%. The % TST with an SaO2 < 90% was 17 +/- 29%. There was a significant inverse correlation between the AHI and TST (r=-0.78, p<0.001), and AHI and SE (r=-0.71, p<0.001) as well as the AHI and AI (r=-0.84, p<0.001). There was also a significant inverse correlation between the BMI and SE (r=-0.49, p=0.03). In addition, there was significant inverse correlation between % TST with an SaO2 < 90% and TST (r=-0.46, p=0.04). There was no correlation between TST, SE, or AI and FEV1 %Pred, FVC %Pred, CT-Derived % Emphysema, or CT-Derived % Gas Trapping. Conclusion(s): In patients with COPD-OSA overlap syndrome, sleep quality, as measured by TST, SE, and AI appears to be mostly influenced by the severity of the patient's OSA rather than the severity of their obstructive airways disease.