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

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 untreated 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 patients 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/m) 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.