Sleep quality and effects of position on sleep apnea in East Asian children

Objectives: To assess whether obstructive sleep apnea syndrome (OSAS) affects sleep architecture and quality in East Asian children, and also to assess the effects of body position during sleep on respiratory disturbance during sleep. Materials and methods: We enrolled 50 consecutive East Asian children with habitual snoring between 2007 and 2009. Nineteen children had OSAS (apnea-hypopnea index, AHI ≥ 5; OSAS group) and 31 children were simple snorers (control group). They underwent polysomnography and physical examination of their nasal and oral cavities with a roentgenogram of the nasopharynx. Sleep architecture and other polysomnographic variables were compared between the OSAS and control groups. The effect of body position during sleep on respiratory disturbance was examined, and also in relation to obesity and adeno-tonsillar size. Results: There was a decrease in total sleep time and in sleep efficiency, as well as increased arousal and heart rate (P< 0.05) in the OSAS group. Sub-analysis of AHI according to sleep posture showed that AHI is higher when the patient is in the supine position than in the non-supine position (P = 0.032). The presence of OSAS and kissing tonsils were contributing factors to the positional difference in AHI (P< 0.05). Obesity and adenoid hypertrophy did not affect the positional difference of AHI. Conclusions: OSAS may have a greater influence on the sleep architecture of East Asian children, and East Asian children may have a higher AHI when sleeping in the supine position. Tonsillar hypertrophy and the presence of OSAS are possible contributing factors for positional difference of AHI in East Asian children.