Use of inhaled corticosteroids and the risk of hospitalisation for pneumonia in children with asthma: a nationwide cohort study.

BACKGROUND:The potential association between the use of inhaled corticosteroids (ICS) and the risk of pneumonia among adults is disputed and paediatric-specific evidence is scarce. AIM:To assess the potential association between ICS, use and the risk of hospitalisation for pneumonia among children (age 2-17 years) with asthma. METHODS:This was a cohort study based on nationwide data from routine clinical practice in Sweden (January 2007 to November 2021). From 425 965 children with confirmed asthma, episodes of new ICS use and no use were identified using records of dispensed drugs. We adjusted for potential confounders with propensity score overlap weighting and the risk of a hospitalisation with pneumonia as primary diagnosis was estimated. Multiple subgroup and sensitivity analyses were also performed. RESULTS:We identified 249 351 ICS (mean follow-up of 0.9 years) and 214 840 no-use (mean follow-up of 0.7 years) episodes. During follow-up, 369 and 181 events of hospitalisation for pneumonia were observed in the ICS and no-use episodes, respectively. The weighted incidence rates of hospitalisation for pneumonia was 14.5 per 10 000 patient-years for ICS use episodes and 14.6 for no-use episodes. The weighted HR for hospitalisation for pneumonia associated with ICS use was 1.06 (95% CI 0.88 to 1.28) and the absolute rate difference was -0.06 (95% CI -2.83 to 2.72) events per 10 000 patient-years, compared with no use. CONCLUSIONS:In this nationwide cohort study, we found no evidence of an association between ICS use and the risk of hospitalisation for pneumonia among children with asthma, as compared with no use.