Can sleeping position be correctly identified by OSAS studies?

OBJECTIVE: Positional Obstructive Sleep Apnoea Syndrome (POSAS) is a sub-type of Obstructive Sleep Apnoea Syndrome (OSAS) in which obstructive apnoeas occur mainly in the supine sleeping position. In clinical practice, information on sleep posture is generally gathered by polysomnographic exam (PSG). The current trend in positional therapies consists of position trainers which help to avoid the supine position. The aim of this study is to detect the reliability of different devices on assessing sleeping position, comparing the data with objective evaluation by an infra-red camera. METHODS: We compared the positional results of 4 healthy volunteers obtained from a type III PSG and with a neck-worn sleep position trainer (Night Shift - NS). RESULTS: Data showed that NS is a good tool to assess the position of the trunk, with high rate of agreement with PSG, but in some conditions there are limitations, especially in detecting the real head and neck position and low accordance between NS data and information recorded by infra-red camera. CONCLUSIONS: Our study confirmed that more information about body position during sleep is needed, underling the necessity of developing new technologies that are able to better identify reciprocal body positions.