Keiji Oishi,1 Tsunahiko Hirano,2 Kazuki Hamada,2 Sho Uehara,2 Ryo Suetake,2 Yoshikazu Yamaji,2 Kosuke Ito,2 Maki Asami-Noyama,2 Nobutaka Edakuni,2 Kazuto Matsunaga2 1Department of Medicine and Clinical Science, Graduate School of Medicine, Yamaguchi University, Ube, Yamaguchi, Japan; 2Department of Respiratory Medicine and Infectious Disease, Graduate School of Medicine, Yamaguchi University, Ube, Yamaguchi, Japan Purpose: The 2017 GOLD ABCD classification shifts patients from groups C–D to A–B. Group A was the most widely distributed group in several studies. It would be useful to understand the characteristics for group A patients, but little has been reported concerning these issues. Patients and methods: This was a multicenter cross-sectional study using the COPD Assessment in Practice study database from 15 primary or secondary care facilities in Japan. We investigated the clinical characteristics of group A by stratification according to a mMRC grade 0 or 1. Results: In 1,168 COPD patients, group A patients accounted for approximately half of the patients. Compared with the groups B–D, group A was younger and had a higher proportion of males, higher pulmonary function, and higher proportion of monotherapy with long-acting muscarinic antagonist or long-acting β-agonist. The prevalence of mMRC grade 1 patients was about two-thirds of group A. Compared with the mMRC 0 patients, mMRC 1 patients showed a tendency to have a higher proportion of exacerbations (P=0.054) and had a significantly lower pulmonary function. Regardless of the mMRC grade, 60% of group A patients were treated with monotherapy of long-acting muscarinic antagonist or long-acting β-agonist. Conclusion: Group A patients accounted for approximately half of the patients, and they were younger, had higher pulmonary function, and had lower pharmacotherapy intensity compared with groups B–D. By stratifying according to the mMRC grade 0 or 1 in group A patients, there were differences in the exacerbation risk and airflow limitation. Keywords: COPD, GOLD, mMRC, exacerbation
