Abstract
Rationale: Smoking is associated with higher risk of developing community-acquired pneumonia (CAP), although it is not clear the association of smoking with pulmonary complications, including parapneumonic effusion (PPE). The objective of the study was to assess the influence of smoking on the incidence of PPE in patients with different baseline disorders.
Methods: We conducted a single-centre cohort study of 3779 consecutively collected patients diagnosed with community-acquired pneumonia. We assessed clinical, radiographic and pleural-fluid chemistry and microbiological variables. Patients were classified according to their smoking status.
Measurements and main results: 958 patients (25%) were current smokers at the diagnosis of CAP. The incidence of parapneumonic effusion was higher in smokers compared to non-smokers patients (13% vs 10%, p < 0.001). After adjusting by diferent confounders (including COPD), smoking was independently associated with PPE (OR 1.34 [95% CI, 1.00-1.81], p=0.05). Although near significance, empyema/complicated PPE was not independently associated with smoking (OR 1.51 [95% CI, 0.97-2.37], p=0.07). Current smoking was associated with lower levels of glucose (p=0.001) and pH (p=0.008), and higher evels of protein (p=0.02) and lactic acid dehydrogenase (p=0.001) in the pleural fluid.
Conclusions: Smoking is associated with higher incidence of PPE in patients with CAP and with higher pleural inflammatory markers. Association with empyema/complicated PPE could not be demonstrated in the present study.
- © 2014 ERS
