Table 2.

Comparison of O₂ saturation parameters in different OSA severity groups.

	Groups
Saturation Parameter	No OSA (AHI < 5)	Mild OSA $(15>\mathbf{AHI}\ge 5)$	Moderate OSA $(30>\mathbf{AHI}\ge 15)$	Severe OSA $(\mathbf{AHI}\ge 30)$	Any OSA $(\mathbf{AHI}\ge 5)$	p-Value	p-Value Adjusted
Basal O2 (%)	93.20 (91.75–94.05)	92.00 (90.90–93.40)	92.00 (90.90–93.40)	91.00 (88.80–92.30)	91.6 (90.00–93.00)	<0.0001 <0.0001 *	<0.0001 <0.0001 *
Mean desaturation O2 (%)	89.80 (86.90–91.00)	86.50 (82.40–88.90)	83.95 (76.90–87.00)	75.25 (67.00–83.90)	82.00 (72.90–87.00)	<0.0001 <0.0001 *	<0.0001 <0.0001 *
O2 nadir (%)	88.90 (85.00–90.50)	86.00 (82.10–88.90)	85.10 (79.90–89.00)	82.10 (75.00–86.20)	84.00 (78.10–87.90)	<0.0001 <0.0001	<0.0001 <0.0001

AHI—apnea–hypopnea index, OSA—obstructive sleep apnea. First p-value corresponds to KW p-value for No OSA vs. Mild/Moderate/Severe OSA. Second p-value indicated by * corresponds to UMW p-value for No vs. Any OSA. Adjusted p-value corresponds to difference after adjustment for BMI and AHI values.