Electrocardiogram recording as a screening tool for sleep disordered breathing.

STUDY OBJECTIVES Transient changes in heart rate associated with obstructive apneas have been suggested for screening of sleep disordered breathing (SDB). This study prospectively compares the outcomes of an automated ECG-based SDB screening tool with simultaneous polysomnography. METHODS The previously-developed automated algorithm was applied to a single channel ECG obtained during standard overnight polysomnography (92 subjects) to obtain an apnea-hypopnea index (AHI) estimate. Using AHI thresholds of < 5 and > or =15 to define absence and presence of SDB, respectively, we determined the likelihood ratios of the proposed technique. RESULTS The automated algorithm achieved positive and negative likelihood ratios of 2.16 and 0.08. Estimated and reference AHI were highly correlated (r = 0.88). Pathologically insignificant arrhythmia in some subjects had no discernible impact on the algorithm. CONCLUSIONS ECG-based assessment provides a simple but limited means of recognizing subjects with obstructive sleep apnea.