Risk factors for FEV1 decline in mild COPD and high-risk populations

Shujing Chen,1 Changhui Wang,2 Bing Li,3 Guochao Shi,4 Huiping Li,5 Jing Zhang,1 Yutong Gu,1 Jian Zhou,1 Yuanlin Song,1 Chunxue Bai1 1Department of Pulmonary Medicine, Zhongshan Hospital, Fudan University, 2Department of Pulmonary Medicine, Shanghai Tenth People’s Hospital, 3Department of Pulmonary Medicine, Shanghai Changzheng Hospital, 4Department of Pulmonary Medicine, Rui Jin Hospital, Shanghai Jiao Tong University School of Medicine, 5Department of Pulmonary Medicine, Shanghai Pulmonary Hospital, Shanghai, People’s Republic of China Background: Early diagnosis of COPD is often not achieved due to limited recognition and limited access to the pulmonary function test. Our hypothesis was that lung function decline may be different between populations with mild COPD and those who are at high risk and do not receive treatment. Patients and methods: Subjects with mild COPD and those from a high-risk COPD population were recruited from a community-based COPD epidemiological study after obtaining consent. Baseline clinical characteristics, symptom questionnaire, spirometry, low-dose computed tomography (LDCT) chest scan, and blood plasma biomarker data were collected initially and then 1 year later. Results: A total of 617 participants were recruited, and 438 eventually completed the first-year follow-up visit; 72 participants (46 males) were in the mild COPD group, and 225 participants (165 males) were in the high-risk group. The mean forced expiratory volume in the first second of expiration (FEV1) decline in the mild COPD group was 129 mL, which was significantly higher than the 30 mL decline in the high-risk population group (P=0.005). Group category (odds ratio [OR] =0.230) and COPD Assessment Test (CAT) score (OR =9.912) were independent risk factors for an FEV1% predicted decline of >15% for all participants. In the mild COPD group, patients with a higher CAT (OR =5.310) and Emphysema Index (OR =5.681) were associated with a FEV1% predicted decline of >15% at the first-year follow-up. No factor showed a significantly predictive effect on FEV1 decline in the high-risk COPD group. Conclusion: Group category was an independent influential factor associated with FEV1 decline. Keywords: COPD, biomarker, lung function decline, Emphysema Index, spirometr