천식경과 중 메타콜린 검사 음성화 전환 환자군의 임상적 특성

Abstract

Background: Clinical characteristics of asthmatics undergoing negative conversion of bronchial hyperreactivity in the methacholine bronchial provocation test (M-test) were not completely evaluated yet. We investigated clinical characteristics of negative conversion of bronchial hyperreactivity in asthmatics. Method: We enrolled 57 patients who were treated more than 1 year at our clinic. We compared parameters of clinical data and the PC20 results of the pulmonary function test and M-test between the negative conversion group (NCG) of bronchial hyperreactivity and the control group with persistent bronchial hyperreactivity (CG). Result: Thirty of the 57 asthmatics showed negative conversion of bronchial hyperreactivity in the M-tests and included in NCG. The remaining 27 patients were included in the CG. There were no significant differences in sex, age, smoking history, atopic sensitization and the initial severity of asthma between the NCG and CG. The initial PC20 of the CG (1.31±2.03 mg/mL) was not significantly different from that of NCG (2.34±4.36 mg/mL) either. The mean treatment duration until negative conversion of bronchial hyperreactivity was 5.46±4.28 years. The initial TEC of the NCG (399.29±250.66 /mcL) was lower than that of the CG (608.92±371.74 /mcL)(P=0.018). Eosinophils in induced sputum (%) of the NCG (22.23±21.63%) was also lower than that of the CG (40.85±32.07%)(P=0.021). The initial FEV1 was higher in the NCG (86.06±15.96%) than in the CG (72.37±18.40%)(p=0.004). FEV1/FVC was also higher in the NCG (76.54±9.59%) than in the CG (65.43±11.14)(P＜0.001). QOL scores were not significantly different between both groups. Conclusion: The negative conversion group of bronchial hyperreactivity may show better pulmonary functions and milder eosinophilic inflammation