Analysis of Lateral Decubitus Position During Sleep in Patients With Obstructive Sleep Apnea Using WatchPAT Device

Measurement of sleep parameters in both supine and non-supine positions is important for the diagnosis of positional obstructive sleep apnea (OSA). However, the influence of right and left lateral decubitus positions (RLDP and LLDP, respectively) on sleep parameters is relatively unknown and has not been well investigated. This study was performed to verify the associations between sleep parameters and lateral decubitus sleep position.

A retrospective study was performed on 38 patients who were diagnosed with OSA and underwent surgical interventions from January 2014 to December 2016. Preoperative sleep parameters were evaluated with WatchPAT, and patients who slept sufficiently in both RLDP and LLDP to accurately analyze sleep parameters were enrolled in the study. Basic clinical data including body mass index (BMI) and nasal endoscopic findings of patients were assessed.

The difference in peripheral arterial tonometry apnea-hypopnea index (pAHI) and PAT respiratory disturbance index (pRDI) between RLDP and LLDP showed no association with the side of deviated nasal septum. Patients with higher BMI showed higher pRDI in LLDP than RLDP (p=0.038). The difference in sleep position percentage between RLDP and LLDP was negatively correlated with the difference in pRDI (p=0.023).

Higher BMI patients with OSA might benefit more from sleeping in RLDP than LLDP. Patients slept longer in the lateral decubitus position that produced lower pRDI. Not only supine and non-supine positions, but also RLDP and LLDP need to be evaluated in patients with OSA.