Health status, activity score and dyspnoea grade in chronic bronchitis, COPD and healthy controls in China

Abstract

<b>Background:</b> Chronic bronchitis (CB) is associated with cough and sputum production, but less is known about effects on breathlessness and activity. This analysis compared patients meeting the MRC definition of CB with COPD patients in GOLD grades I-III and healthy never-smoker controls. <b>Methods:</b> Data are drawn from the baseline of COMPASS, a prospective 2.5 year study of COPD in China, that focuses on mild-moderate disease. The protocol has been published (Liang et al. ERJ Open Res. 2021). Spirometry was measured post-bronchodilator. The study is exploratory, so no p values were calculated, but results are expressed as means and 95% confidence intervals (CI). <b>Results:</b> The results from 1899 participants at baseline are tabulated. The health status scores were generally lower than those reported in Western populations. SGRQ, CAT and mMRC scores in CB patients were worse than in non-smoking controls and very similar to GOLD grade I. The mean CAT score in CB was higher than in GOLD grade I and the 95% CIs did not cross. The gender balance in the controls was different from that in the COPD and CB patients, but a very similar pattern was seen in the same analyses split by gender (not shown here). <b>Conclusions:</b> Chronic bronchitis, in the absence of airflow limitation, has an effect on all components of respiratory health status, including activity and dyspnoea that is comparable to GOLD I COPD.