Impact of obesity on response to therapy and pulmonary function in children with asthma

Abstract:

Objective To investigate the effects of obesity on response to therapy and pulmonary function in children with asthma who receive inhaled corticosteroid (ICS) treatment. Methods A total of 129 children with asthma were divided into two groups according to their body mass index: normal weight group (n=64) and obese group (n=65). The asthma control status and pulmonary function were compared between the two groups after one year of ICS treatment. The pulmonary function was expressed as percent forced expiratory volume in 1 second (FEV1%), percent predicted forced vital capacity (FVC%), peak expiratory flow (PEF), peak expiratory flow at 25% of vital capacity (PEF₂₅), and peak expiratory flow at 50% of vital capacity (PEF₅₀). The asthma control status was expressed as complete control rate, partial control rate, and uncontrolled rate. Sixty-eight healthy children were selected as the healthy control group. Results There were significant differences in the indices of pulmonary function between the three groups before treatment (P<0.01); the healthy control group had the best values of pulmonary function, while the obese group had the worst values. After 1 year of treatment, the normal weight group showed significantly more improvements in FEV1% and FVC% than the obese group (P<0.01). However, there were no significant differences in improvements in PEF, PEF₂₅, and PEF₅₀ between the two groups. The complete control rate, partial control rate, and uncontrolled rate in the normal weight group were 72%, 19%, and 9%, respectively, while the rates in the obese group were 28%, 51%, and 22%, respectively; the normal weight group had a significantly better asthma control status than the obese group (P<0.01). Conclusions The asthmatic children with obesity have a significantly less improvement in large airway function and a poorer asthma control status after ICS treatment than those with the normal weight.