Effectiveness of Shin'iseihaito in Asthmatic Patients with Upper Airway Diseases: A Retrospective Cohort Study.

Background: Severe asthma is often associated with sinonasal diseases. Shin'iseihaito is a Japanese traditional herbal medicine, which is used to treat rhinosinusitis. However, its effectiveness in the treatment of asthma has not been elucidated.

Objective: The aims of this study were to examine the effectiveness of Shin'iseihaito in asthmatic patients with upper airway disease and to identify the characteristics of responders.

Methods: The medical records were retrospectively analyzed of asthmatic patients concomitant with upper airway disease in the outpatient department who had been administered Shin'iseihaito at least once from September 2011 to February 2015. They were classified into responders and non-responders, and the differences in characteristics were compared between the two groups.

Results: Shin'iseihaito was effective in 21/40 (52.5%) patients. There was no significant difference between responders and non-responders with regard to age, sex, or age of asthma onset. However, the frequency of aspirin intolerance, the treatment step of asthma, and serum immunoglobulin E levels were significantly higher in responders than they were in non-responders (p = 0.022, p = 0.017, and p = 0.017, respectively). The frequency of occurrence of concomitant eosinophilic chronic rhinosinusitis was not significantly different in both groups.

Conclusion: Shin'iseihaito could be a potential alternative for the treatment of asthma in patients with upper airway diseases.