TABLE 3

Univariable and multivariable linear regression analysis to determine predictors of optimal continuous positive airway pressure (n=198)

Variables	Univariable model			Multivariable model^#
Variables	β	se	p-value	β	se	p-value
Demographic factors
Age	0.170	0.054	0.002	0.273	0.054	<0.001
Sex
Male (ref.)
Female	−0.490	0.441	0.268	−0.530	0.389	0.174
Race
Chinese (ref.)
Malay	0.574	0.442	0.196	0.544	0.418	0.194
Indian and others	−0.356	0.610	0.560	−0.129	0.525	0.806
Adenotonsillectomy history
Yes (ref.)
No	−0.057	0.425	0.894	−0.664	0.383	0.085
Diagnosis of DS
No (ref.)
Yes	1.023	0.618	0.099	2.120	0.595	<0.001
PSG variables
OAHI	0.048	0.007	<0.001	0.053	0.033	0.115
ODI₃	0.049	0.008	<0.001	−0.045	0.039	0.255
REM RDI	0.039	0.006	<0.001	0.017	0.011	0.108
SpO₂ nadir	−0.078	0.017	<0.001	−0.027	0.025	0.276
BMI z-score	0.207	0.077	0.008	0.280	0.086	0.001

DS: Down syndrome: PSG: polysomnography; OAHI: obstructive apnoea-hypopnoea index; ODI₃: 3% oxygen desaturation index; REM: rapid eye movement; RDI: respiratory disturbance index; SpO₂: arterial oxygen saturation measured by pulse oximetry; BMI: body mass index. ^#: R²=0.314.