Abstract
BACKGROUND: The 2017 GOLD guidelines revised assessment of COPD by eliminating the FEV(1) criterion. AIM: First, we explored the redistribution of 2011 GOLD groups by reference to the 2017 GOLD criteria. Second, we investigated the characteristics of GOLD B patients and the natural course of GOLD B patients according to the 2017 GOLD guidelines. METHODS: In total, 2,010 COPD patients in the Korean COPD Subgroup Study cohort were analyzed at baseline and 1 year after enrollment. RESULTS: The 2011 GOLD C patients were redistributed to the 2017 A (64.5%) and C (35.4%) groups. The 2011 GOLD D patients were redistributed to the 2017 B (61.6%) and D (38.6%) groups. The GOLD B patients constituted 62.7% of all patients according to the 2017 classification. Such patients exhibited higher % predicted FEV(1) values, longer six-minute walk distances, fewer symptoms, and lower inflammatory marker levels than GOLD D patients. Most GOLD B patients remained in that group (69.1%), but 13.8% progressed to group D at 1-year follow-up. The factors associated with progression from GOLD B to GOLD D were older age, higher modified Medical Research Council (mMRC) and St George's Respiratory Questionnaire (SGRQ) symptom scores, and a lower % predicted FEV(1) value. CONCLUSION: Severe symptoms, poorer health status, and greater airflow limitation increased patients' risk of exacerbation and progression from group B to group D when the 2017 GOLD criteria were applied.