Influence of Age on the Risk of Severe Exacerbation and Asthma Control in Childhood

Abstract

Background. Asthma is a heterogeneous disease but it is a common observation that children tend to “grow out of their asthma.” Objective. The aim was to specifically assess the influence of age on the occurrence of a severe exacerbation (at least 3 days use of systemic corticosteroid – international 2009 definition) and of the achievement of control (GINA guidelines) in children treated for asthma. Our study was controlled for amount of therapy and for season. Methods. Children under inhaled corticosteroid (ICS) were enrolled over two 2-month periods (autumn, spring). Duration of oral steroid treatment and of symptoms, dose of ICS and long-acting beta-agonist were recorded for the past 3 months. Results. Three hundred and fifty-nine children (110 girls) were included (48 [<2 years], 116 [2–6 years], 107 [6–10 years], 88 [>10 years]) during autumn (n = 175) and spring (n = 184), all treated by ICS (mean daily dose ± SD = 378 ± 250 μg). Among the 359 children, 133 (37%) experienced at least one severe exacerbation, and control was observed in 111 (31%) children. A multivariate logistic regression model demonstrated that age, season, and ICS dose are independent risk factors for exacerbation, whereas age is the only predictor of control. The odds ratio of exacerbation and control are 0.85 (95% CI, 0.78–0.92, p < .0001) and 0.85 (95% CI, 0.79–0.91, p < .0001) per year of increase in age, respectively. Conclusions. From infancy to adolescence, each year of life reduces per se the risk of a severe exacerbation by 15% and similarly increases the achievement of control in children treated for asthma.

• asthma
• childhood
• control
• exacerbation

Acknowledgments

We thank Isabelle Berros for expert technical assistance. The Unité de Recherche Clinique was responsible for data collection and statistical analyses (LT).

BM acquired the data. BM, LT, and CD conceived this study. LT performed the statistical analyses. All authors have drafted the submitted article or revised it critically for important intellectual content and have provided final approval of the version to be published.

Declaration of Interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.