ObjectiveWorldwide, community-acquired pneumonia (CAP) is a common infection that occurs in older adults, who may have pulmonary comorbidities, including chronic obstructive pulmonary disease (COPD). Although there have been clinical studies on the coexistence of CAP with COPD, there remain some controversial findings. This review presents the current status of COPD in CAP patients, including the disease burden, clinical characteristics, risk factors, microbial etiology, and antibiotic treatment.

Data SourcesA literature review included full peer-reviewed publications up to January 2018 derived from the PubMed database, using the keywords "community-acquired pneumonia" and "chronic obstructive pulmonary disease".

Study SelectionPapers in English were reviewed, with no restriction on study design.

ResultsCOPD patients who are treated with inhaled corticosteroids are at an increased risk of CAP and have a worse prognosis, but data regarding the increased mortality remains unclear. Although Streptococcus pneumoniae is still regarded as the most common bacteria isolated from patients with CAP and COPD, Pseudomonas aeruginosa is also important, and physicians should pay close attention to the occurrence of antimicrobial resistance, particularly in these two organisms.

ConclusionsCOPD is a common and important predisposing comorbidity in patients who develop CAP. COPD often aggravates the clinical symptoms of patients with CAP, complicating treatment, but generally does not appear to affect prognosis.