Phenotypic approaches to positional therapy for obstructive sleep apnoea

I thank Drs. Oksenberg and Gadoth for highlighting the important role that positional therapy may play in the treatment ofobstructive sleep apnoea (OSA) according to a phenotypic approach[1]. The recent phenotyping review in this journal[2] focused on physiological mechanisms with potential clinical application. Clinical phenotypes such as supine OSA has been the feature of other recent comprehensive reviews and research articles that eloquently highlight the therapeutic potential of positional therapy and how changes in body position alter the phenotypic traits that cause OSA (e.g.,[3e5]). Specifically, recent work has provided insight into the mechanisms by which supine avoidance may improve pharyngeal stability (e.g., changes in airway mechanics and lung volume) via position dependent alterations in key phenotypic traits and the characteristics of those most likely to respond [4,5,9]. In addition, as Drs. Oksenberg and Gadoth and others point out[1,3,6,7], recent advances in positional device therapy technology to facilitate supine avoidance[6,8], have considerable potential as a simple,affordable alternative to existing therapies for OSA. Indeed, people who have supine only or supine dominant OSA represent a considerable proportion of the adult OSA patient population[10,11]