Current Situation of Asthma Therapy by Allergists in Primary Medical Facilities in Japan

Abstract

Background: To reduce deaths from asthma, further use of inhaled corticosteroids (ICS) in accordance with the guidelines is required. The present study was conducted because specialists are responsible for increasing the use of guidelines, but the current state of asthma care provided by specialists in primary clinical settings has not been clarified. Methods: In collaboration with five primary medical facilities throughout Japan, severity of asthma, contents of asthma therapy, and the implementation rate of pulmonary function testing and peak flow measurements were analyzed for 1007 outpatients ≥40 years old with stable bronchial asthma. In all patients, peak inspiratory flow (PIF) was measured during examination. Results: Either ICS or ICS/long-acting beta 2 agonist (LABA) was used in almost all patients with at least mild persistent asthma. Although treatments adhered to the guidelines, therapeutic steps did not match asthma severity in many patients with mild intermittent asthma. Large gaps existed between facilities that measure pulmonary function and PEF in daily clinical practice and those that do not. While mean PIF value for all subjects was well maintained at 102.0 ± 29.1 L/min, some patients may not have been able to inhale efficiently in terms of PIF (5.1% of Turbuhaler® users and 5.7% of Diskhaler® users). Conclusions: When stepping down asthma therapy, some confusion in policy may exist, leading to guideline mismatches. Differences in the implementation of pulmonary function and PEF measurements, as indicators for long-term management, need to be minimized among specialists. For maintaining effective inhalation, inspiratory flow should be periodically checked.

Keywords

• asthma
• inhaled corticosteroid (ICS)
• peak expiratory flow (PEF)
• peak inspiratory flow (PIF)
• pulmonary function test