A Comparison of Polysomnography and a Portable Home Sleep Study in the Diagnosis of Obstructive Sleep Apnea Syndrome

OBJECTIVE: To validate the role of a portable sleep monitor device (SNAP) in the diagnosis of obstructive sleep apnea syndrome (OSAS). Inter-reader variability was also assessed for both PSG and SNAP. STUDY DESIGN AND SETTING: Sixty consecutive adults referred for PSG at The University of Chicago Sleep Disorder Clinic were prospectively enrolled. RESULTS: There was no significant difference between total number of apnea and hypopnea, respiratory disturbance index (RDI), and minimum oxygen obtained by PSG and SNAP, but there was a significant difference between sleep time and mean oxygen. Pearson's correlation coefficient for RDI > or = 15 was 0.92. CONCLUSION: There was a significant correlation of RDIs between SNAP and PSG. SNAP has good sensitivity, specificity, positive and negative predictive values. Differences between SNAP and PSG could be attributed to inter-reader variability and not necessarily due to technical limitations of SNAP. SNAP is an excellent tool for the diagnosis of OSAS in the laboratory setting. Future studies should be performed to evaluate SNAP's accuracy in the home setting in the diagnosis of OSAS. EBM RATING: B-2.