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

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.

Interleukin-10 and interleukin-5 balance in patients with active asthma, those in remission, and healthy controls

BACKGROUND: The immunological mechanisms of asthma remission remain unclear although several reports have suggested that balance between T helper (Th) 2 cytokines and regulatory cytokines is related. OBJECTIVE: To study the balance between interleukin (IL) 10 and IL-5 in asthma clinical remission. METHODS: We measured the numbers of IL-5 and IL-10 producing cells in peripheral blood mononuclear cells stimulated with mite antigen obtained from patients with active asthma (group A, n = 18), patients in clinical remission (group R, n = 15) and nonatopic healthy controls (group H, n = 14). RESULTS: The numbers of IL-5 producing cells in groups A and R were significantly higher than in group H. The number of IL-5 producing cells was lower in group R than in group A, although the difference was not statistically significant. The number of IL-10 producing cells was higher in group R than in group A, although again the difference was not statistically significant. There was a significant difference in the number of IL-10 producing cells between groups A and H but not between groups R and H. The ratio of the number of IL-10 to IL-5 producing cells was highest in group H followed by groups R and A, and the differences were statistically significant for each pair of groups. CONCLUSION: Our study suggests that the IL-10/IL-5 balance is related to clinical asthma. The balance differs between patients in clinical remission and healthy controls, suggesting that allergic inflammation may continue even after clinical asthma remission.