Proton-pump inhibitors and the risk of antibiotic use and hospitalisation for pneumonia

Elizabeth E Roughead, Emmae N Ramsay, Nicole L Pratt, Philip Ryan and Andrew L Gilbert
Med J Aust 2009; 190 (3): 114-116.


Objective: To determine whether proton-pump inhibitor (PPI) use is associated with hospitalisations for pneumonia and with antibiotic use.

Design and setting: 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.

Participants: 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.

Main outcome measures: 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.

  • Elizabeth E Roughead1
  • Emmae N Ramsay2
  • Nicole L Pratt2
  • Philip Ryan2
  • Andrew L Gilbert3

  • 1 School of Pharmacy and Medical Sciences, University of South Australia, Adelaide, SA.
  • 2 Data Management and Analysis Centre, Discipline of Public Health, University of Adelaide, Adelaide, SA.
  • 3 Quality Use of Medicines and Pharmacy Research Centre, Sansom Institute, University of South Australia, Adelaide, SA.


This research was funded by the Australian Government Department of Veterans’ Affairs as part of the delivery of the Veterans’ Medicines Advice and Therapeutics Education Services (Veterans’ MATES) project.

Competing interests:

None identified.

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