Pranlukast reduces asthma exacerbations during autumn especially in 1- to 5-year-old boys

Abstract

Background: Leukotriene receptor antagonists have been used to prevent virus-induced asthma exacerbations in autumn. Its efficacy, however, might differ with age and sex.

Objective: This study aimed to investigate whether pranlukast added to usual asthma therapy in Japanese children during autumn, season associated with the peak of asthma, reduces asthma exacerbations. It was also evaluated the effect of age and sex on pranlukast's efficacy.

Methods: A total of 121 asthmatic children aged 1 to 14 years were randomly assigned to receive regular pranlukast or not according to sex, and were divided in 2 age groups, 1-5 years and 6-14 years. The primary outcome was total asthma score calculated during 8 weeks by using a sticker calendar related to the days in which a child experienced a worsening of asthma symptoms. This open study lasted 60 days from September 15 to November 14, 2007.

Results: Significant differences in pranlukast efficacy were observed between sex and age groups. Boys aged 1 to 5 years had the lower total asthma score at 8 weeks (p = 0.002), and experienced fewer cold episodes (p = 0.007). There were no significant differences between pranlukast and control group in total asthma score at 8 weeks (p = 0.35), and in the days in which a child experienced a worsening of asthma symptoms (p = 0.67).

Conclusion: There was a substantial benefit of adding pranlukast to usual therapy in asthmatic children, especially in boys aged 1 to 5 years, during autumn season.

Keywords: Age; Asthma; Child; Exacerbations; Pranlukast; Sex.

Fig. 1. Patients flow diagram.

Fig. 2. Differences between pranlukast and control groups in total asthma score (A) and number of days with worse asthma symptoms (B). No significant differences were observed between pranlukast and control groups

Fig. 3. Differences between pranlukast and control groups in number of colds (A) and number of days with fever (B). The pranlukast group presented a decreasing trend of number of colds and lower number of days with fever than controls.

Fig. 4. (A, B) Girls: differences between pranlukast and control groups in total asthma score (A) and number of colds (B). (C, D) Boys: differences between pranlukast and control groups in total asthma score (C) and number of colds (D). One- to 5-year-old boys in the pranlukast group had a significant lower total asthma score and also less number of cold episodes than control group.