Treatment effect of head extension by cervical collar on moderate obstructive sleep apnea–A randomized controlled trial

Abstract

As available treatments in obstructive sleep apnea are all associated with side-effects or adherence problems, there is a need for alternative treatment options. In this randomized, open, parallel-group intervention study, the effect of head extension by cervical collar was evaluated in patients with moderate obstructive sleep apnea. One-hundred patients with moderate obstructive sleep apnea (apneas and hypopneas per estimated hours asleep = respiratory events index: 15–30) were randomized to either lifestyle intervention, or cervical collar in combination with lifestyle intervention. Both groups received lifestyle advice. In addition, the treatment group was treated with a cervical collar, which allows adjustment of head extension, during sleep. Assessment with questionnaires and polygraphy were performed at baseline and after 6 ± 2 weeks. A linear regression model was used to assess a total effect on respiratory events index, which was the primary endpoint. In the intention-to-treat analysis, the cervical collar in combination with lifestyle intervention group decreased their respiratory events index (p = 0.008) and oxygen desaturation index (p = 0.008) more than the lifestyle intervention group, with a mean difference of −4.5 and −4.3, respectively. In the sub-analysis, there was a clear effect on respiratory events index in the supine position (mean difference between the groups −9.1, p = 0.018) but not on non-supine apnea–hypopnea index (−2.3, p = 0.17). We conclude that head extension by cervical collar during sleep resulted in improved respiratory events index and oxygen desaturation index values in patients with moderate obstructive sleep apnea. Cervical collar can be a second-line treatment option in this group, especially in positional obstructive sleep apnea.