Table 5.

Percentage of Time Spent with Oxygen Saturation Below 90% Stratified by FEV₁ Quartiles and AHI Categories

FEV1 Quartile	AHI (Events/h)
	<5.0	5.0–14.9	15.0–29.9	≥30.0	P Value*
≥ 3.19 L	0.90 (5.33)	2.32 (6.20)	5.91 (10.60)	15.88 (16.73)	<0.001
2.61–3.18 L	0.68 (4.06)	2.32 (6.74)	6.61 (10.73)	18.17 (19.94)	<0.001
2.10–2.60 L	0.95 (5.430)	3.88 (10.56)	7.89 (12.99)	19.85 (21.65)	<0.001
≤2.09 L	2.30 (10.38)	4.84 (11.68)	9.96 (16.11)	18.70 (20.29)	<0.001
P value†	<0.001	<0.001	0.002	0.240

Definition of abbreviation: AHI = apnea–hypopnea index.

^*P value for trend across AHI categories, within each FEV₁ quartile.

^†P value for trend across FEV₁ quartiles, within each AHI category.