Chronic obstructive pulmonary disease severity is associated with severe pneumonia

CONTEXT: Chronic obstructive pulmonary disease (COPD) is a heterogeneous disorder, and various aspects of COPD may be associated with the severity of pneumonia in such patients. AIMS: We examined the risk factors associated with severe pneumonia in a COPD population. METHODS: We performed a retrospective observational study using a prospectively collected database of pneumonia patients who were admitted to our hospital through emergency department between 2008 and 2012. Patients with hospital-acquired pneumonia and those with an immunocompromised status were excluded. RESULTS: Of 148 pneumonia patients with COPD for whom chest computed tomography (CT) scans were available, 106 (71.6%) and 42 (28.4%) were classified as non-severe and severe pneumonia, respectively. Multivariate logistic regression analysis revealed that the severity of airflow limitation [odds ratio (OR), 2.751; 95% confidence interval (CI), 1.074-7.050; P = 0.035] and the presence of emphysema on a chest CT scan (OR, 3.366; 95% CI, 1.104-10.265; P = 0.033) were independently associated with severe pneumonia in patients with COPD. CONCLUSIONS: The severity of COPD including the airflow limitation grade and the presence of pulmonary emphysema were independently associated with the development of severe pneumonia.