Efficacy of leukotriene receptor antagonists in asthma treatment and analysis of background factors evaluated by a questionnaire survey among physicians

: The efficacy of leukotriene receptor antagonists (LTRAs) in the treatment of asthma and the involvement of various patient background factors were investigated. A questionnaire was used to survey the physicians of 1,600 asthma patients regarding the use of LTRAs, whether treatment was being continued or had been discontinued, and reasons for continuation or discontinuation. The results showed that 797 patients had used an LTRA, with 468 having used pranlukast (P), 294 having used montelukast (M) and 25 having used zafirlukast. For the remaining 10 patients, either the drug name was unknown or multiple LTRAs had been used. The P Group was slightly younger in age (median: P, 55 years, M, 57 years) and had a higher frequency of mild, intermittent disease (P: 20.3%; M:11.2%). The P Group also had a higher percentage of patients who continued taking an LTRA because the drug was "clearly effective" (P: 34.6%; M: 17.3%), and a lower percentage of patients who discontinued the drug because the drug was "ineffective" (P: 2.6%; M:19.0%). Logistic regression analysis showed the following as independent factors contributing to efficacy of the LTRA in the treatment of the asthma (R2 = 0.19): P as the drug used (p < 0.01); allergic rhinitis not present as a complication (p < 0.01); and mild severity of asthma (p = 0.02). Further, the present findings indicate that LTRAs are highly effective for patients who have mild asthma without complication by allergic rhinitis. Further investigation is necessary to determine differences in efficacy among different LTRAs.