Abstract
Introduction: The aim of this study is to know if the short term effects of the personal exposure to nitrogen dioxide (NO2) and physical activity (PA) interact on children's lung function.
Methods: We measured personal exposure to NO2 and PA during 1 week in 2 different seasons in 42 children from Sabadell (Spain). Using a phone, location and PA of children were recorded with a minute resolution. Exposure to NO2 was obtained by combining the location of the children with the Sabadell NO2 LUR map with hourly correction from the NO2 background ambient monitor. At the end of each week, respiratory function was assessed by spirometry, following ATS/ERS recommendations. The analysis (mixed linear models) included PA, NO2 exposure, height, sex, age and BMI as fixed effects and child as a random effect.
Results: 36 children (58%male, 7-9years, FEV1 1.65±0.4L, 67%normoweight) were included. The results of the mixed model showed an increase in FEV1(beta 0.12, 95%CI 0.01;0.24) and FVC (beta 0.16, 95%CI 0.01;0.31) for each hour of daily PA performed during previous week, only in children with a personal exposure to NO2 below the median (73 ug·m−3) (Figure 1).
Conclusion: Exposure to NO2 prevents the benefits of PA on lung function in children.
Figure 1. FEV1 and FVC least mean squares of the multivariate mixed linear model according to personal exposure to NO2 and PA of previous week.
- Copyright ©the authors 2017