Obstructive Sleep Apnea is an Independent Risk Factor for Hospital Readmission

Study Objectives: Hospital readmissions are an important metric of quality and safety. This study seeks to characterize the relationship between readmissions and obstructive sleep apnea (OSA). A better understanding of this relationship could be utilized to develop preventative measures and reduce readmission rates. Methods: A retrospective review of patients discharged over a 24-month period to a Department of Defense hospital was conducted. Medical records review provided demographic data, presence of OSA and comorbid diseases, and whether readmission occurred within 30 days of discharge. Statistical analysis assessed risk factors for readmission, and multivariate analysis was performed. Next, 125 readmitted patients with OSA were randomly selected for detailed chart review and compared to a matched cohort that was not readmitted. Results: Of 22,261 unique patients discharged, 1,899 (8.5%) were readmitted. Patients with OSA had a readmission rate of 11.4% versus 7.6% for patients without OSA (P < .00001). Multivariable analysis revealed an odds ratio of 1.46 for readmission in patients with OSA (P < .0001). For the detailed chart review of 250 patients, length of hospital stay differed for the readmitted and non-readmitted groups (5.1 versus 3.6 days; P = .007). Apnea-hypopnea index (24.1 versus 27.2 events/h; P= .48) was similar between the groups. Also, inpatient (27.2% versus 26.4%) and outpatient (38.4% versus 37.6%) positive airway pressure (PAP) treatment rates were not different. Conclusions: This study found OSA to be an independent risk factor for readmission within 30 days of discharge. PAP therapy appears to be underutilized in patients with known OSA. Additional studies are needed to define the relationship between OSA, PAP adherence, and hospital readmission.