The Accuracy of Portable Monitoring in Diagnosing Significant Sleep Disordered Breathing in Hospitalized Patients

BACKGROUND Polysomnograms are not always feasible when sleep disordered breathing (SDB) is suspected in hospitalized patients. Portable monitoring is a practical alternative; however, it has not been recommended in patients with comorbidities. OBJECTIVE We evaluated the accuracy of portable monitoring in hospitalized patients suspected of having SDB. DESIGN Prospective observational study. SETTING Large, public, urban, teaching hospital in the United States. PARTICIPANTS Hospitalized patients suspected of having SDB. METHODS Patients underwent portable monitoring combined with actigraphy during the hospitalization and then polysomnography after discharge. We determined the accuracy of portable monitoring in predicting moderate to severe SDB and the agreement between the apnea hypopnea index measured by portable monitor (AHIPM) and by polysomnogram (AHIPSG). RESULTS Seventy-one symptomatic patients completed both tests. The median time between the two tests was 97 days (IQR 25-75: 24-109). Forty-five percent were hospitalized for cardiovascular disease. Mean age was 52±10 years, 41% were women, and the majority had symptoms of SDB. Based on AHIPSG, SDB was moderate in 9 patients and severe in 39. The area under the receiver operator characteristics curve for AHIPM was 0.8, and increased to 0.86 in patients without central sleep apnea; it was 0.88 in the 31 patients with hypercapnia. For predicting moderate to severe SDB, an AHIPM of 14 had a sensitivity of 90%, and an AHIPM of 36 had a specificity of 87%. The mean±SD difference between AHIPM and AHIPSG was 2±29 event/hr. CONCLUSION In hospitalized, symptomatic patients, portable monitoring is reasonably accurate in detecting moderate to severe SDB.