Long term survival after admission for COPD exacerbation: A comparison with the general population

Abstract

Background and objective: Life expectancy data of COPD patients in comparison to the general population are primarily based upon long-term population cohort studies. These studies are limited by a poor definition of clinically significant COPD. The key element in the course of COPD is a clinical exacerbation. Therefore, this study investigated 15-year survival following hospitalization for an exacerbation of COPD in comparison to the general population.

Methods: A number of 4229 subjects was studied, including 845 hospitalized COPD patients and 3384 age and sex matched controls. Mortality risks were assessed using Kaplan-Meier survival curves, and hazard rate ratios for death were estimated using Cox proportional hazards regression models, for each Gold Class separately.

Results: Overall 15-year survival was 7.3% in the COPD group and 40.6% in the general population. Survival was 24%, 11.1%, 5.3% and 0% for COPD GOLD I-IV. The mean life expectancy following hospitalization was 9.7, 7.1, 6.1 and 3.4 years for stage GOLD I-IV and 10.2 years for the general population. Overall, negative prognostic factors were age, male gender, low FEV1, low TLCO, respiratory insufficiency, Charlson comorbidity class, ICU-admission and exacerbation frequency. Factors differed among GOLD stages.

Conclusions: The 15-year survival for hospitalized COPD patients is reduced by 82% in comparison to the general population. This indicates a more deleterious course of clinically significant COPD in comparison to population cohorts. As such, every possible effort should be taken to reduce exacerbations in a personalized way.

Keywords: COPD; Exacerbation; Survival.