Comparison of WatchPAT to polysomnography measurement of apnea-hypopnea index and obstructive sleep apnea severity in adolescents with overweight and obesity.

Study objectives: The prevalence of obstructive sleep apnea (OSA) increases dramatically in adolescents with overweight or obesity. The gold standard for diagnosis of OSA is in-laboratory polysomnography (PSG). However, access to PSG can be challenging, necessitating development of alternative devices. This study aimed to compare the accuracy of WatchPAT, a device that indirectly detects apnea and hypopnea events through peripheral arterial tonometry, to PSG in adolescents with overweight and obesity.

Methods: 38 participants (15.5±1.6 years; 76% female; 40% Hispanic/Latino; BMI 97.7±2.0 percentile) were analyzed. Correlation, agreement, sensitivity, specificity, and concordance between WatchPAT with PSG-derived measures of apnea-hypopnea index (AHI) and OSA severity were conducted. A subset (n=21) underwent subjective assessment of nasal flow sensor reliability and video characteristics to evaluate possible underestimation of PSG-assessed AHI.

Results: Mean bias between WatchPAT- and PSG-derived AHI was 16.9±13.4 events/hour (95% CI 12.5-21.3). WatchPAT overestimated OSA severity compared to PSG in 89% of participants. Sensitivity was 62-100% and specificity was 5.5-32% across all OSA severity levels. Of the subset with subjective assessment of PSG data, 38% had nasal flow sensor reliability <75%, 14% had underestimated AHI, and 28% had probably underestimated AHI. However, these characteristics did not fully explain the discrepancy between WatchPAT and PSG measurements.

Conclusions: The WatchPAT device showed a significant discrepancy compared to the gold-standard PSG in measurement of AHI and accuracy of OSA severity in adolescents with overweight or obesity. Future research is needed to understand pathophysiological differences to enhance assessment of OSA in this high-risk population.