TABLE 1

Comparison of characteristics of subjects with and without obstructive sleep apnoea (OSA)

	Non-OSA	OSA	p-value
Subjects	131	60
Male/female	44/87	24/36	0.4^#
Age years	12 (6–18)	11 (5–17)	0.1^¶
Height m	1.55 (1.14–1.83)	1.51 (1.07–1.86)	0.1^¶
Weight kg	71.0 (30.4–129.8)	67.3 (28.0–137.0)	0.3^¶
BMI z-score	2.5 (1.5–3.5)	2.5 (1.7–4.1)	0.6^¶
Waist circumference cm	92.4±13.6	93.2±17.1	0.7⁺
WHR	0.89 (0.75–1.02)	0.92 (0.79–1.04)	<0.001^¶
Fat mass %	36.9 (25.7–60.4)	36.1 (27.3–53.1)	0.9^¶
TST min	512 (169–637)	512 (293–648)	0.6^¶
oAHI events·h⁻¹	0.5 (0.0–1.9)	4.9 (2.0–67.3)	<0.001^¶
RDI events·h⁻¹	0.85 (0.00–4.80)	5.90 (2.00–67.70)	<0.001^¶
Mean S_pO₂ %	97.2 (91.2–98.2)	96.7 (91.9–98.6)	0.001^¶
S_pO₂ nadir %	93 (80–100)	91 (81–100)	<0.001^¶
TST95 %	99.7 (25.6–100.0)	98.0 (2.4–100.0)	<0.001^¶
ODI events·h⁻¹	0.3 (0.0–8.4)	0.8 (0.0–33.8)	<0.001^¶
N1 %TST	2 (0–13)	2 (0–16)	0.6
N2 %TST	51 (28–72)	45 (8–65)	<0.001
N3 %TST	22 (4–48)	28 (8–65)	<0.001
REM %TST	23 (0–36)	23 (5–37)	0.7

Data are presented as n, mean±sd or median (range), unless otherwise stated. BMI: body mass index; WHR: waist-to-hip ratio; TST: total sleep time; oAHI: obstructive apnoea–hypopnoea index; RDI: respiratory disturbance index; S_pO₂: arterial oxygen saturation measured by pulse oximetry; TST95: TST with S_pO₂ >95%; ODI: oxygen desaturation index; N1–N3: sleep stages; REM; rapid eye movement. ^#: Chi-squared test; ^¶: Mann–Whitney U-test; ⁺: independent sample t-test. p≤0.05 was considered statistically significant.