In a population-based study conducted in Scotland, the use of commonly prescribed acid-suppressant medications (ASMs), such as proton pump inhibitors (PPIs), has been linked to an increased risk of intestinal infections with Clostridium difficile and Campylobacter bacteria, which can cause serious illness. The findings were published in the British Journal of Clinical Pharmacology.
The study involved 188,323 subjects exposed to PPIs and H2 receptor antagonists (H2RAs) and 376,646 controls who were not exposed to ASMs between 1999 and 2013. The primary outcome measure was a positive stool test for C. difficile, Campylobacter, Salmonella, Shigella, or Escherichia coli O157.
Compared with individuals in the community who did not take acid-suppressant drugs, those who did had 1.7-times and 3.7-times increased risks of C. difficile and Campylobacter infections, respectively. Among hospitalized patients, those using acid-suppressant medications had 1.4-times and 4.5-times increased risks, respectively. The adjusted hazard ratios for culture-positive diarrhea for the PPI- and H2RA-exposed cohort compared with the unexposed cohort were 2.72 for samples submitted from the community and 1.28 for samples submitted from hospitals.
Although acid-suppressant therapy is commonly considered to be relatively free from adverse effects, the new findings suggest that there are significant adverse gastrointestinal consequences of their use, according to the investigators.
“Users of these medications should be particularly vigilant about food hygiene as the removal of stomach acid makes them more easily infected with agents such as Campylobacter, which is commonly found on poultry,” said senior author Professor Thomas MacDonald.