New diagnostic tools to screen and assess a still too underestimated disease: the role of the wrist-worn peripheral arterial tonometry device-a systematic review

Purpose Home sleep apnea testing devices aim to overcome the drawbacks of polysomnography (PSG). Among these, the WatchPAT (WP) (Itamar Medical Ltd., Caesarea, Israel) has recently been introduced on the market for diagnosis of Obstructive Sleep Apnea (OSA). The aim of this review was to provide a comprehensive overview of the studies validating the WP for the diagnosis of sleep-disordered breathing through comparison with PSG. Methods A systematic review was performed to identify all clinical studies concerning WP validation compared with PSG as diagnostic tools. A qualitative analysis of the data was conducted. Results In this review, 18 studies were included for a total of 1049 patients, aged 8 to 70 years old, with 74 of these being pediatric patients. In most studies, patients completed an overnight PSG and simultaneously wore WatchPAT in a sleep laboratory, while others compared the results obtained on two different nights. Both protocols showed good results in terms of AHI, ODI, RDI, and SO2. Moreover, some studies calculated the sensitivity and specificity of the WP ranging from 87 to 96% and from 66 to 80%, respectively. Excellent results were found also in pediatric patients. Conclusion The WP represents an effective and convenient tool for OSA diagnosis compared to standard reference systems.