(1312) Improvements in Management of Obstructive Sleep Apnoea Following Subsidy for Ambulatory Sleep Study

Introduction: Compared to an in-laboratory polysomnogram (PSG), a level 3 ambulatory sleep study with watch peripheral arterial tonometry (WatchPAT) device is more convenient, comfortable, readily available, cheaper and less labor intensive. An earlier study conducted by the corresponding author found that patients who underwent WatchPAT had earlier diagnosis and treatment of OSA compared to those who had PSG, resulting in significant healthcare cost savings. The aim of this study was to further investigate if subsidised rates for WatchPAT would lead to greater improvements in OSA management.

Methods: Government subsidy for WatchPAT was introduced in 2019. Retrospective chart reviews of patients who underwent WatchPAT 1 year prior and 1 year following subsidy implementation (January 2018 to December 2019) was performed. Patients were eligible for subsidy if they had excessive daytime sleepiness; and at least 2 of the following 3 criteria: habitual loud snoring; witnessed apnea, gasping or choking; and/or diagnosed hypertension. WatchPAT pick up rate, time to diagnosis and treatment were reviewed.

Results: Of the 595 patients who underwent WatchPAT over the 2-year period, 188 WatchPAT studies were performed prior to subsidy whereas 407 were performed after subsidy implementation. There was significantly higher WatchPAT pick up rate (p = 0) after subsidy implementation. There was no significant difference in time to diagnosis (p = 0.155), but there was significant reduction in time to treatment with continuous positive airway pressure (CPAP) device (p = 0.002). Among patients who declined WatchPAT, 6% and 5% were due to cost concerns prior to and following subsidy respectively. There was no significant difference in patients who declined WatchPAT due to cost concerns before and after subsidy implementation (p = 0.424). The most common cited reason for declining WatchPAT was because patients were not keen for any sleep study.

Conclusions: WatchPAT subsidy leads to higher pick up rate and reduction in time to CPAP treatment, although there was no difference in time to diagnosis.