title: Proton-pump inhibitors and the risk of antibiotic use and hospitalisation for pneumonia.
abstract: OBJECTIVE
  To determine whether proton-pump inhibitor (PPI) use is associated with hospitalisations for pneumonia and with antibiotic use.
  
  
  METHODS
  Historical cohort study in the Australian veteran population, conducted from 1 January 2002 to 30 December 2006, comparing veterans exposed to PPIs with those not exposed.
  
  
  METHODS
  All 185,533 veterans who were Gold Card holders (ie, eligible for all health services subsidised by the Department of Veterans' Affairs) and aged 65 years and over at 1 January 2002 and had been prescribed at least one medicine in the previous 6 months.
  
  
  METHODS
  The primary endpoint was hospitalisation for pneumonia. Secondary endpoints included hospitalisation for bacterial pneumonia and dispensings of antibiotics commonly used to treat respiratory tract infections.
  
  
  RESULTS
  After adjustment for potential confounders, we found an increased risk of hospitalisation for pneumonia among those exposed to PPIs compared with the unexposed group (rate ratio [RR], 1.16; 95% CI, 1.11-1.22). The risk was not increased for bacterial pneumonia (RR, 1.13; 95% CI, 0.98-1.31), which made up 8% of pneumonia cases. An increased risk of antibiotic dispensings was observed among those exposed to PPIs (RR, 1.23; 95% CI, 1.21-1.24).
  
  
  CONCLUSIONS
  PPI dispensings were found to be associated with a small but significant increased risk of hospitalisation for pneumonia. While the increased risk is small, the prevalent use of PPIs means that many people could be affected.
authors.affiliation: School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA. Libby.Roughead@unisa.edu.au
authors.forename: Elizabeth E
authors.initials: EE
authors.lastname: Roughead
authors.forename: Emmae N
authors.initials: EN
authors.lastname: Ramsay
authors.forename: Nicole L
authors.initials: NL
authors.lastname: Pratt
authors.forename: Philip
authors.initials: P
authors.lastname: Ryan
authors.forename: Andrew L
authors.initials: AL
authors.lastname: Gilbert
mesh_terms: D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001315:Australia; D015331:Cohort Studies; D016001:Confidence Intervals; D004363:Drug Utilization / Q000706:statistics & numerical data; D005260:Female; D006760:Hospitalization / Q000706:statistics & numerical data*; D006801:Humans; D008297:Male; D018410:Pneumonia, Bacterial / Q000453:epidemiology / Q000209:etiology*; D054328:Proton Pump Inhibitors / Q000009:adverse effects*; D018570:Risk Assessment; D012307:Risk Factors; D014729:Veterans Disability Claims
chemical_list: D000900:Anti-Bacterial Agents; D054328:Proton Pump Inhibitors