Characteristics and longitudinal progression of COPD GOLD B

Abstract

Background The characteristics and natural history of GOLD B patients are not well described. Aims Objectives To assess the clinical characteristics and natural history of GOLD B patients over one year in a multicentre cohort of COPD patients in the COPDMAP study. We aimed to identify the subgroup of patients who progressed to GOLD D (unstable GOLD B patients) and identify characteristics associated with progression. Methods 370 COPD patients were assessed at baseline and 12 months thereafter. Demographics, lung function, health status, 6 minute walk test and levels of systemic inflammation were assessed. Students t tests and Mann Whitney-U test were used as appropriate. Results 107 (28.9%) of patients were categorised as GOLD B at baseline. These GOLD B patients had similar FEV1 to GOLD A patients (66% predicted). More GOLD B patients were current smokers ( p =0.031), had chronic bronchitis ( p =0.0003) and cardiovascular comorbidities ( p =0.019) compared to GOLD A. At 12 months, 25.3% of GOLD B patients progressed to GOLD D. These patients who progressed (unstable patients) had worse health status and symptoms (SGRQ-C Total, 50.0 v 41.1, p =0.019 and CAT, 21.0 v 14.0, p =0.006) and lower FEV 1 (60% v 69% p =0.014) at baseline compared to stable patients who remained in GOLD B. Conclusions Unstable GOLD B patients who progressed to GOLD D had a higher level of symptoms at baseline. A high symptom burden may predict an increased likelihood of disease progression in GOLD B patients.