Inhaled Corticosteroids Use and Risk of Invasive Pneumococcal Disease Risk in a Population-based Study.

RATIONALE Use of inhaled corticosteroid (ICS) is associated with increased pneumonia risk, but the risk of invasive pneumococcal disease (IPD) associated with ICS is not characterized. OBJECTIVE The aim was to test the hypothesis that use of ICS increase the risk of IPD. METHODS Cases were persons 20 to 65 years of age included in a Swedish national registry of invasive infection caused by Streptococcus pneumoniae, classified as any IPD, as well as the subset of IPD with pneumonia. The case index date was the day the infection was diagnosed. Six controls for each case, matched for gender, age and region, were selected from the Swedish national population registry and were assigned the index date of their corresponding case. Current and past users of ICS were defined by the last prescriptions dispensed within 60 or 61-365 days of the index date. Non-users were defined as no dispensed prescription the last 365 days. Current users were characterized by use of fluticasone or budesonide. We used conditional logistic analysis, including matching and covariates, to estimate the odds ratios (OR) and 95% confidence intervals (95% CI) of IPD, IPD with pneumonia and IPD without pneumonia associated with current or past use of ICS. RESULTS Current use of ICS increased the risk for IPD and IPD with pneumonia (OR 1.71, 95% CI 1.39-2.10 and OR 1.94, 95% CI 1.53-2.47, respectively), but there was no statistical association between current use of ICS and IPD without pneumonia (OR 1.18, 95% CI 0.78 - 1.80). Past use of ICS increased the risk for IPD and IPD with pneumonia, but not for IPD without pneumonia. Among current ICS users, the odds for IPD were similar for budesonide (OR 1.34; 95% CI 1.14 - 1.57) and fluticasone (OR 1.41; 95% CI 1.04 - 1.90). Among current ICS users, the odds for IPD with pneumonia were slightly higher, but of similar magnitude to each other for both budesonide and for fluticasone. CONCLUSIONS ICS use is associated with increased risk of IPD and IPD with pneumonia. The risk is driven by IPD with pneumonia. We found similar risks for budesonide and fluticasone.