The association between inhaled corticosteroid and pneumonia in COPD patients: the improvement of patients' life quality with COPD in Taiwan (IMPACT) study.

To investigate the association between inhaled corticosteroid (ICS) exposure patterns and the risk of pneumonia in chronic obstructive pulmonary disease (COPD) patients, we performed a nested case-control study. Between 1998 and 2010, 51,739 patients, including 19,838 cases of pneumonia, were matched to 74,849 control subjects selected from a cohort of COPD patients using ICSs via risk-set sampling of the database constructed by the National Health Research Institutes of Taiwan. After adjusting for covariates, the current use of ICSs was associated with a 25% increase in the risk of pneumonia (odds ratio [OR] =1.25, 95% confidence interval [CI] =1.20-1.30), and there was an increase in the OR with increase in the average daily dosage. Additionally, users of fluticasone/salmeterol, fluticasone, and either fluticasone/salmeterol or fluticasone were more likely to be at a higher risk of pneumonia (OR =1.35, 95% CI =1.28-1.41; OR =1.22, 95% CI =1.10-1.35; and OR =1.33, 95% CI =1.27-1.39, respectively). In contrast, there were no statistically significant associations between the risk of pneumonia and the use of budesonide/formoterol, budesonide, or either budesonide/formoterol or budesonide. In conclusion, ICSs are significantly associated with an increased risk of pneumonia in COPD patients. The effect is prominent for fluticasone-containing ICSs but not for budesonide-containing ICSs.