Table 6

Adjusted multivariate models for OSAS severity measures within adolescents with OSAS

OSAS measureVariableUA anatomy model Pcrit model Full model
β (95% CI)*p Valueβ (95% CI)*p Valueβ (95% CI)*p Value
AHI (events/hour) ATV 0.48 (0.29 to 0.67) <0.0001 0.45 (0.25 to 0.65) <0.0001
NPAV0.06 (−0.15 to 0.27)0.5740.05 (−0.18 to 0.28)0.651
Pcrit (Activated)0.21 (−0.08 to 0.50)0.1500.03 (−0.24 to 0.30)0.805
Pcrit (Hypotonic)0.12 (−0.19 to 0.43)0.4300.15 (−0.11 to 0.40)0.245
% sleep time with SpO2<90% ATV 0.52 (0.34 to 0.70) <0.0001 0.54 (0.35 to 0.72) <0.0001
NPAV0.22 (0.02 to 0.42)0.031 0.28 (0.07 to 0.49) 0.009
Pcrit (Activated)0.16 (−0.14 to 0.45)0.281−0.14 (−0.39 to 0.10)0.242
Pcrit (Hypotonic)0.20 (−0.11 to 0.51)0.194 0.30 (0.07 to 0.54) 0.012
SpO2 nadir (%)ATV −3.74 (−6.11 to −1.37) 0.003 −4.01 (−6.68 to −1.34) 0.004
NPAV−0.91 (−3.56 to 1.75)0.492−1.16 (−4.20 to 1.87)0.441
Pcrit (Activated)−1.15 (−4.54 to 2.23)0.4930.72 (−2.84 to 4.29)0.682
Pcrit (Hypotonic)0.53 (−3.03 to 4.09)0.7640.06 (−3.32 to 3.44)0.970
Peak ETCO2 (mm Hg)ATV0.40 (−1.16 to 1.96)0.6060.66 (−1.05 to 2.38)0.436
NPAV−0.52 (−2.26 to 1.23)0.550−0.03 (−1.98 to 1.92)0.975
Pcrit (Activated)−1.02 (−2.95 to 0.92)0.293−1.24 (−3.52 to 1.05)0.278
Pcrit (Hypotonic)1.41 (−0.63 to 3.45)0.1681.42 (−0.75 to 3.59)0.192
% sleep time with ETCO2>50 ATV0.18 (−0.37 to 0.72)0.5210.34 (−0.26 to 0.94)0.251
NPAV0.14 (−0.47 to 0.76)0.6370.37 (−0.31 to 1.05)0.282
Pcrit (Activated)−0.32 (−1.01 to 0.36)0.346−0.59 (−1.39 to 0.21)0.141
Pcrit (Hypotonic)0.23 (−0.49 to 0.95)0.5220.35 (−0.41 to 1.11)0.351
  • *Beta coefficient and 95% CI from linear regression model, interpreted as the expected change in outcome for a 1 SD increase in continuous variables or associated with the indicated group for categorical variables.

  • †p Value from linear regression model.

  • ‡Measures natural log+1 transformed for normality; significant (p<0.05) associations are shown in bold.

  • AHI, apnoea hypopnoea index; ATV, adenotonsillar volume; ETCO2, end-tidal carbon dioxide; NPAV, nasopharyngeal airway volume; OSAS, obstructive sleep apnoea syndrome; Pcrit, critical closing pressure; SpO2, arterial oxygen saturation; UA, upper airway.