The sleep position trainer: a new treatment for positional obstructive sleep apnoea.

Background: Positional obstructive sleep apnoea (POSA), defined as a supine apnoea-hypopnoea index (AHI) twice or more as compared to the AHI in the other positions, occurs in 56 % of obstructive sleep apnoea patients. Positional therapy (PT) is one of several available treatment options for these patients. So far, PT has been hampered by compliance problems, mainly because of the usage of bulky masses placed in the back.