Hospitalization Due to Community-Acquired Pneumonia in Patients with Chronic Obstructive Pulmonary Disease: Incidence, Epidemiology & Outcomes

Background: Community-acquired pneumonia (CAP) is an important complication in patients with chronic obstructive pulmonary disease (COPD). This study aimed to define incidence, and outcomes of COPD patients hospitalized with pneumonia in the city of Louisville, and to estimate the burden of disease in the U.S. population.   Methods: This was a secondary analysis of a prospective population-based cohort study of residents in Louisville, Kentucky, 40 years old and older, from June 1st, 2014 to May 31st , 2016. All adults hospitalized with CAP were enrolled. The annual incidence of pneumonia in COPD patients in Louisville was calculated and the total number of adults with COPD hospitalized in the U.S. was estimated. Clinical outcomes included time to clinical stability (TCS), length of hospital stay (LOS), and mortality. Results: From a Louisville population of 18,246 patients living with COPD, 3,419 pneumonia hospitalizations were documented during the two-year study. The annual incidence was 9,369 patients hospitalized with pneumonia per 100,000 COPD population, corresponding to an estimated 506,953 adults with COPD hospitalized due to pneumonia in the US.  Median TCS and LOS were 2 and 5 days respectively. Mortality during hospitalization was 5.6%. The mortality of COPD patients at 30-days, 6-months, and 1-year was 11.9%,24.3%, and 33.0%, respectively.   Conclusions: There was an annual incidence of 9,369 cases of hospitalized CAP per 100,000 COPD patients in the city of Louisville. This was an approximately 18-fold greater incidence of CAP in COPD patients than in those without COPD, resulting in a high morbidity and financial burden. Funding: This work was supported primarily by the Division of Infectious Diseases, University of Louisville, Kentucky. Partial support was given by Pfizer Inc. Declaration of Interest: There are no conflicts of interest for any of the authors in this manuscript. Ethical Approval: The study was approved by the University of Louisville (UofL) Institutional Review Board (IRB #11.0613) and by the research offices at each participating hospital. Study consents were waived.