Undiagnosed OSA May Significantly Affect Outcomes in Adults Admitted for COPD in an Inner-City Hospital

Abstract

BACKGROUND: COPD is the second most common cause of hospital admission in the United States. OSA is a highly prevalent and underdiagnosed condition that may affect the outcome of COPD. RESEARCH QUESTION: We hypothesized that presence of unrecognized and untreated OSA will increase hospital readmissions in patients admitted for COPD exacerbation. STUDY DESIGN AND METHODS: We reviewed patients admitted for COPD exacerbation from May 2017 through July 2018 who were also screened for previously unrecognized and un- treated OSA with a sleep questionnaire, and who subsequently underwent a high-resolution pulse oximetry or portable sleep monitoring study. We compared the rates of 30-, 90-, and 180-day readmission or death across OSA categories and compared overall survival in pa- tients with and without OSA. RESULTS: Of 380 patients admitted for COPD exacerbation, 256 were screened for OSA with a sleep questionnaire (snoring, tiredness during daytime, observed apnea, high BP). Of these, 238 underwent an overnight high-resolution pulse oximetry/portable sleep monitoring. Of the 238 total patients, 111 (46.6%) were found to have OSA; 28.6% had mild, 9.7% moderate, and 8.4% severe OSA. Baseline characteristics and demographics were compared between the cohorts of participants with OSA and without OSA and were similar except that patients with OSA had a higher mean BMI (33.9 vs 30.3 kg/m2) and an increased prevalence of heart failure (19.8% vs 7.1%). For patients with COPD and mild OSA, odds of 30-day readmission were 2.05 times higher than for patients without OSA (32.4% vs 18.9%). Additionally, odds of 30-day readmission were 6.68 times higher for patients with moderate OSA vs patients without OSA (60.9% vs 18.9%) and 10.01 times high for patients with severe OSA vs patients without OSA (70% vs 18.9%). Readmission rates were also greater at 90 and 180 days. All- cause mortality was lower for patients without OSA than for patients with OSA (P < .01). The time to hospital readmission or death was shorter with greater OSA severity (P < .01). INTERPRETATION: Patients hospitalized for COPD exacerbation and who have unrecognized OSA; 30-, 90-, and 180-day readmission rates; and 6-month mortality rates are higher than in those without OSA.