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 (AHI(PM)) and by polysomnogram (AHI(PSG)). 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 AHI(PSG), SDB was moderate in 9 patients and severe in 39. The area under the receiver operator characteristics curve for AHI(PM) 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 AHI(PM) of 14 had a sensitivity of 90%, and an AHI(PM) of 36 had a specificity of 87%. The mean±SD difference between AHI(PM) and AHI(PSG) was 2±29 event/hr. CONCLUSION: In hospitalized, symptomatic patients, portable monitoring is reasonably accurate in detecting moderate to severe SDB.