[Survey of asthma control and anti-asthma medication use among Japanese adult patients].

Background: The purpose of this study was to clarify disease control and medication use among Japanese adult asthmatic patients.

Method: We studied the reality of adult outpatients and inpatients with asthma at 26 national hospitals across Japan who visited the clinic between September and October 2006. Anti-asthma medication use and asthma control were assessed. Disease severity was determined according to the 2006 Japanese Guideline. The results of this study were compared with those obtained in 1995 after standardization by age and gender.

Results: Of 2524 patients, the prevalence of inhaled corticosteroid use in 2006 was 89%, which was higher than that in 1995 (62%). Although the prevalence of patients who experienced asthma hospitalization once or more in their lifetime in 1995 was 73%, that in 2006 decreased to 49%. The prevalences of hospitalization and unscheduled doctor visit in the last 12 months in 2006 were 8% and 25% respectively. The percentage of patients in 2006 who did not reach an acceptable level of control despite treatment at step 4 of the 2006 Japanese guideline was 15%.

Conclusions: A favorable change in asthma medication use and asthma control was observed from 1995 to 2006; that is, increased prevalence of inhaled corticosteroid use and decreased prevalence of patients who experienced hospitalization for asthma once or more in their lifetime. However, some patients remained symptomatic despite high-dose inhaled corticosteroid treatment.