Table 4. Comparison of changes in AHI and BMI between surgical treatment and untreated groups stratified by follow-up duration

Variables	Surgical treatment group	Untreated group	t-value†	p-value†
Changes in AHI (/hr)
Overall (n=31/43)	–7.1±36.9	0.5±24.5	1.00	0.324
<36 months (n=20/29)	–26.1±27.5	–0.3±23.2	3.45	0.001*
≥36 months (n=11/14)	27.4±25.0	1.9±27.9	–2.40	0.025*
Changes in BMI (kg/m2)
Overall (n=31/43)	0.52±1.75	–0.32±2.29	–1.80	0.076
<36 months (n=20/29)	–0.08±1.39	–0.02±2.26	0.12	0.904
≥36 months (n=11/14)	1.62±1.87	–0.98±2.29	–3.09	0.005*

p<0.05.
The t-values and p-values were calculated using the independent samples t-test.
AHI: apnea-hypopnea index, BMI: body mass index.