Table 3.

Associations between sleep position and breathing-characteristic estimated effects of sleep position.

	Nonsupine Position	Supine Position	P
AHI events	Ref	1.59	<.0001
ODI events	Ref	2.1	<.0001
SpO2	Ref	−0.04	.4
SpO2 nadir	Ref	−0.9	.006
SpO2 <90%	Ref	0.0002	.04

AHI and ODI estimated effects were obtained from a mixed Poisson model for event counts and represent the supine-to-nonsupine ratio of events; the Poisson model was adjusted for time spent in each position and continuous breathing measures (SpO₂, SpO₂ nadir, SpO₂ <90%) obtained from a mixed linear model and represents their mean differences in supine versus nonsupine sleep positions. AHI = apnea-hypopnea index; ODI = oxygen desaturation index; SpO₂ = peripheral oxygen saturation.