Effects of Obstructive Sleep Apnea and Obesity on Thirty-Day Readmissions in Patients with Chronic Obstructive Pulmonary Disease: A Cross-Sectional Mediation Analysis.

Abstract

RATIONALE\nComorbidity is a significant driver of health status and healthcare utilization in chronic obstructive pulmonary disease (COPD). Obstructive sleep apnea (OSA) portends poorer outcomes, while obesity is protective. We describe the prevalence and influence of these comorbidities on COPD readmissions.\n\n\nMETHODS\nWe collated discharge records for COPD exacerbations spanning 2010-2016 from the Nationwide Readmissions Database using Medicare s Hospital Readmissions Reduction Program criteria, with OSA-COPD overlap identified by concomitant diagnosis code for OSA. We used mixed-effects logistic regression to predict readmission odds. A cross-sectional mediation analysis was performed to evaluate the extent that OSA attenuated obesity s impact on readmission.\n\n\nRESULTS\nOf 1,662,983 qualifying COPD discharges, 19.1% carried a diagnosis of obesity and 12.9% had OSA, with both diagnoses present in 7.8%. In unadjusted analyses, obesity (OR 1.04, 95%CI [1.03-1.05], P<0.001) and OSA (OR 1.11 [1.10-1.13], P<0.001) had increased readmission odds. In models adjusted for patient and hospital characteristics, 71% of readmission risk from obesity was attributable to OSA. When additionally adjusted for Charlson Comorbidity Index, we found that OSA remained a significant risk factor (OR 1.05 [1.03-1.06], P<0.001), while obesity remained protective (OR 0.96 [0.94-0.97], P<0.001) even after accounting for OSA.\n\n\nCONCLUSIONS\nA significant proportion of COPD patients suffer comorbid OSA and obesity with resultant readmission risk. Interestingly, obesity s protective effect attenuates readmission odds from OSA. Taken together, OSA and aggregate comorbidity influence readmissions in COPD patients. Testing for and treating OSA-COPD overlap may provide a mechanism to reduce avoidable readmissions.