We sought to determine the risk factors for and outcomes associated with rapid lung function decline in a cohort of subjects followed for up to 11 years.
We analyzed data from 4,923 adult participants, aged 65 and older at baseline, in the Cardiovascular Health Study (CHS). We classified subjects using a modification of the GOLD criteria for COPD, and added a “restricted” category (FEV1/FVC > 70% and FVC < 80% predicted). We used Cox proportional hazard models to determine the risk of lung function decline over four years on subsequent mortality and COPD hospitalizations, after adjusting for age, race, sex, smoking status, and other factors.
Of the participants in our initial cohort, 3388 (68.8%) had spirometry at the Year 4 visit. Participants with GOLD Stages 3 or 4 COPD at baseline were less likely than normal subjects to have follow-up spirometry ( 52.7% vs. 77.9%, p < 0.01) and were more likely to be in the most rapidly declining quartile of FEV1 (28.2% vs, 21.3%, p < 0.01), with an FEV1 loss of at least 3.4% annually. Overall, membership in the most rapidly declining quartile of FEV1 from baseline to Year 4 was modestly associated with risk of COPD hospitalization (adjusted Hazard Ratio [HR] 1.6, 95% confidence interval [CI] 1.3, 2.0) and all-cause death (adjusted HR 1.5, 95% CI: 1.2, 1.7) over an additional seven years of follow-up.
More rapid decline of lung function was independently associated with a modest increased risk of COPD hospitalizations and deaths in an elderly cohort of US participants.
Monitoring changes in spirometry may be useful in determining the risk if exacerbations and death in elderly patients with COPD.
David Mannino, Grant monies (from industry related sources) GlaxoSmithKline, Pfizer; Consultant fee, speaker bureau, advisory committee, etc. GlaxoSmithKline, Pfizer, Ortho Biotech, Boehringer Ingelheim.