Comparison of positional therapy to CPAP in patients with positional obstructive sleep apnea

We hypothesized that positional therapy would be equivalent to continuous positive airway pressure (CPAP) at normalizing the apnea-hypopnea index (AHI) in patients with positional obstructive sleep apnea (OSA).

Thirty-eight patients (25 men, 49 +/- 12 years of age, body mass index 31 +/- 5 kg/m2) with positional OSA (nonsupine AHI <5 events/h) identified on a baseline polysomnogram were studied. Patients were randomly assigned to a night with a positional device (PD) and a night on CPAP (10 +/- 3 cm H2O).

Positional therapy was equivalent to CPAP at normalizing the AHI to less than 5 events per hour (92% and 97%, respectively [p = 0.16]). The AHI decreased from a median of 11 events per hour (interquartile range 9-15, range 6-26) to 2 (1-4, 0-8) and 0 events per hour (0-2, 0-7) with the PD and CPAP, respectively; the difference between treatments was significant (p < 0.001). The percentage of total sleep time in the supine position decreased from 40% (23%-67%, 7%-82%) to 0% (0%-0%, 0%-27%) with the PD (p < 0.001) but was unchanged with CPAP (51% [36%-69%, 0%-100%]). The lowest SaO2 increased with the PD and CPAP therapy, from 85% (83%-89%, 76%-93%) to 89% (86%-9%1, 78%-95%) and 89% (87%-91%, 81%-95%), respectively (p < 0.001). The total sleep time was unchanged with the PD, but decreased with CPAP, from 338 (303-374, 159-449) minutes to 334 (287-366, 194-397) and 319 (266-343, 170-386) minutes, respectively (p = 0.02). Sleep efficiency, spontaneous arousal index, and sleep architecture were unchanged with both therapies.

Positional therapy is equivalent to CPAP at normalizing the AHI in patients with positional OSA, with similar effects on sleep quality and nocturnal oxygenation.