Debunking the Notion That Proton-Pump Inhibitors Cause Bacterial OvergrowthA large, retrospective study using glucose hydrogen breath testing found no association.
Whether or not alterations in the gastric pH level increase susceptibility for enteric infections has long been debated. Proton-pump inhibitor (PPI) use, which causes such alterations, has been linked with small intestinal bacterial overgrowth (SIBO), a condition associated with bloating, diarrhea, and malabsorption (Clin Gastroenterol Hepatol 2010; 8:504). However, findings across multiple studies are mixed.
To evaluate if the prevalence of SIBO differs between PPI users and nonusers, investigators retrospectively reviewed charts of 1191 consecutive patients who underwent glucose hydrogen breath testing (GHBT) for SIBO during a 6-year period at a single tertiary care center. Primary indications for GHBT included bloating, dyspepsia, or gas (507 patients); diarrhea (337); abdominal pain (166); and nausea, vomiting, or both (55). Most patients (70%) were female, about half (48%) were taking a PPI, and 81% had been diagnosed with irritable bowel syndrome. Breath samples for both hydrogen (H2) and methane were collected before ingestion of 50 g of oral glucose and every 20 minutes for 2 hours after ingestion. A positive GHBT result was assessed using four different cutoff values.
GHBT positivity was not associated with PPI use. However, it was associated with older age (adjusted odds ratio, 1.03; 95% confidence interval, 1.01–1.04 using a cutoff of H2 >20 parts per million), use of antidiarrheal medication (adjusted OR, 1.99; 95% CI, 1.15–3.44 using a cutoff of H2 >20 ppm), and with diarrhea (adjusted OR, 1.53; 95% CI, 1.13–2.09 using a cutoff of H2 >10 ppm).
Citation(s):Ratuapli SK et al. Proton pump inhibitor therapy use does not predispose to small intestinal bacterial overgrowth. Am J Gastroenterol 2012 May; 107:730.
