Sleep-disordered breathing children: Measurement of nasal nitric oxide and fractional exhaled nitric oxide.

OBJECTIVE: To assess the clinical significance of nasal nitric oxide (nNO) and fractional exhaled nitric oxide (FeNO) concentrations in children with sleep-disordered breathing (SDB).

METHODS: Enrolled in this study were 30 children with SDB and 15 healthy children. The nNO and FeNO concentrations were measured noninvasively using a NIOX MINO system (Aerocrine AB, Solna, Sweden). SPSS statistics 20.0 software (IBM SPSS statistics 20.0, Armonk, NY, USA) was used to analyze the data.

RESULTS: The median (25th and 75th percentiles) nNO concentration of SDB children measured in parts per billion (ppb) was 111.0 (44.0; 349.0) ppb; FeNO concentration of SDB children was 12.0 (9.8; 14.0) ppb. The nNO concentration of healthy children was 52.0 (22.0; 139.0) ppb; FeNO concentration of healthy children was 12.0 (10.0; 16.0) ppb. Compared to healthy children, nNO concentration was significantly higher in children with SDB (Z = -2.215, P = 0.027). Correlation analysis showed that SDB children's nNO concentration directly correlated with apnea-hypopnea index (AHI; r = 0.429, P = 0.018), and inversely correlated with nadir oxygen saturation (SaO2; r = -0.482, P = 0.007). No other polysomnographic parameters significantly correlated with nNO concentration.

CONCLUSION: Our data suggest that nNO concentration might be useful for diagnosis and evaluation of disease severity in SDB children. Furthermore, these results suggest that nNO concentration has a greater prognostic value than FeNO concentration.