Objective: To evaluate the sleep architecture and hypoxia and clinical features of habitual snoring children with an obstructive sleep apnea-hypopnea index (OAHI) 1 to 5.
Method: The polysomnographic data of 267 children aged from 2 to 16 years with habitual snoring were analyzed retrospectively, and the clinical features were analyzed in 108 of the children. The recruited children were divided into primary snoring group (PS group, OAHI≤1), obstructive sleep apnea hypopnea syndrome (OSAHS) group (1<OAHI≤5 and obstructive apnea index≤1), lowest oxygen saturation (LSpO2≤0.92) and OSAHS group (OAHI>5 or dostructive apnea index>1, LSpO2<0.92).
Result: The oxygen desaturation index of the intermediate OSAHS group (3.8±0.4) was significantly higher than that of PS group (1.6±0.1) (χ2=34.5, P<0.01). The LSpO2 of intermediate OSAHS group was significantly lower than that of PS group (89(87,91) vs. 93(91,94), χ2=40.2, P<0.01). Comparing to the PS group, the non-rapid eye movement 1 ratio (N1%) was significantly higher (19.0±1.2 vs. 14.2±0.1, χ2=14.1, P<0.01), and the non-rapid eye movement 3 ratio (N3%) was significantly lower (24.4±1.0 vs. 29.0±1.1, P<0.01) in the intermediate OSAHS group. The pediatric questionnaire score intermediate OSAHS group was higher than PS (0.41±0.19 vs. 0.28±0.14, χ2=8.52, P=0.01). The adenoids-nasopharynx ratio was higher than that of PS group (0.70±0.07 vs. 0.62±0.10, χ2=8.96, P=0.01). The hypertrophy of tonsil was higher than PS group (2(1,2) vs. 1(1,2), χ2=7.95, P<0.05).
Conclusion: Hypoxia and abnormal sleep structure are present in HS children with an OAHI of 1 to 5, and they also have the clinical features of OSAHS.