Ventilatory function in pre-school children snorers and nonsnorers.

BACKGROUND: The value of flow-volume curves alterations for screening for sleep apnoea is controversial in adults. OBJECTIVE: The purpose of the present study was to assess the possible value of flow-volume curves, in snoring pre-school children to detect upper airway abnormal dynamics. METHODS: We analysed ventilatory function of 190 children aged 5 to 6 years from nine kindergartens in Nancy, France, according to the presence or absence of snoring as declared by their parents. RESULTS: More than half (103 = 54%) of the children never snored; 26 (= 13.7%) snored only with colds, 42 (22.1%) snored occasionally, and 19 (= 10%) snored habitually. The "saw tooth" sign described in adults by Sanders et al in 1981 was absent in all the children in this study, and the height-adjusted forced expiratory volume in one second (FEV1/m2) was similar across the four groups. The height-adjusted peak expiratory flow (PEF/m2) decreased uniformly (but insignificantly) from the group of non-snorer (2.11 +/- 0.381/s/m2) through the group of children snoring with colds. (2.05 +/- 0.37) to the group of children snoring occasionally (1.99 +/- 0.33); no significant decrease was found in the group of habitual snorers (2.06 +/- 0.36). CONCLUSION: In this group of young children, we were unable to find the alteration of the expiratory flow-volume loop described in part of the studies in adults. We cannot, however, exclude an alteration of the inspiratory arm of the loop, as this was not recorded by us. Our results, suggesting a reduction in peak expiratory flow with increase in frequency of snoring need to be validated in a larger population of children.