FEV1 is a stronger mortality predictor than FVC in patients with moderate COPD and with an increased risk for cardiovascular disease

Abstract

Andras Bikov,1,2 Peter Lange,3,4 Julie A Anderson,5 Robert D Brook,6 Peter MA Calverley,7 Bartolome R Celli,8 Nicholas J Cowans,9 Courtney Crim,10 Ian J Dixon,9 Fernando J Martinez,11 David E Newby,12 Julie C Yates,10 Jørgen Vestbo1,2 1Manchester University NHS Foundation Trust, Manchester Academic Health Science Centre, Manchester, UK; 2Division of Infection, Immunity & Respiratory Medicine, University of Manchester, Manchester, UK; 3Medical Department, Herlev and Gentofte Hospital, Herlev, Denmark; 4Section of Epidemiology, Department of Public Health, University of Copenhagen, Copenhagen, Denmark; 5Research & Development, GlaxoSmithKline, Middlesex, UK; 6University of Michigan Health System, Ann Arbor, MI, USA; 7University of Liverpool, Department of Medicine, Clinical Sciences Centre, University Hospital Aintree, Liverpool, UK; 8Pulmonary and Critical Care Division, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA, USA; 9Statistics & Programming, Veramed Ltd., Twickenham, UK; 10Research & Development, GlaxoSmithKline, Research Triangle Park, NC, USA; 11Division of Pulmonary and Critical Care Medicine, Weill Cornell Medicine, New York, NY, USA; 12British Heart Foundation Centre for Cardiovascular Science, University of Edinburgh, Edinburgh, UKCorrespondence: Andras Bikov 2nd Floor ERC Building, Wythenshawe Hospital, Southmoor Road, Manchester M23 9LT, UKTel [phone]Fax [phone]Email [email protected]: Chronic obstructive pulmonary disease (COPD) is one of the leading causes of death worldwide. Impaired lung function is associated with heightened risk for death, cardiovascular events, and COPD exacerbations. However, it is unclear if forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) differ in predictive value.Patients and Methods: Data from 16,485 participants in the Study to Understand Mortality and Morbidity (SUMMIT) in COPD were analyzed. Patients were grouped into quintiles for each lung function parameter (FEV1 %predicted, FVC %predicted, FEV1/FVC). The four highest quintiles (Q2–Q5) were compared to the lowest (Q1) to assess their relationship with all-cause mortality, cardiovascular events, and moderate-to-severe and severe exacerbations. Cox-regression was used, adjusted for age, sex, ethnicity, body-mass index, smoking status, previous exacerbations, cardiovascular disease, treatment, and modified Medical Research Council dyspnea score.Results: Compared to Q1 (< 53.5% FEV1 predicted), increasing FEV1 quintiles (Q2 53.5– 457.5% predicted, Q3 57.5– 461.6% predicted, Q4 61.6– 465.8% predicted, and Q5 ≥ 65.8%) were all associated with significantly decreased all-cause mortality (20% (4– 34%), 28% (13– 40%), 23% (7– 36%), and 30% (15– 42%) risk reduction, respectively). In contrast, a significant risk reduction (21% (4– 35%)) was seen only between Q1 and Q5 quintiles of FVC. Neither FEV1 nor FVC was associated with cardiovascular risk. Increased FEV1 and FEV1/FVC quintiles were also associated with the reduction of moderate-to-severe and severe exacerbations while, surprisingly, the highest FVC quintile was related to the heightened exacerbation risk (28% (8– 52%) risk increase).Conclusion: Our results suggest that FEV1 is a stronger predictor for all-cause mortality than FVC in moderate COPD patients with heightened cardiovascular risk and that subjects with moderate COPD have very different risks.Keywords: airflow limitation, cardiovascular risk, exacerbation, lung function, lung volumes, death rate

Keywords

• airflow limitation
• cardiovascular risk
• exacerbation
• lung function
• lung volumes
• death rate