Association between proton pump inhibitor use and spontaneous bacterial peritonitis in cirrhotic patients with ascites.

BACKGROUND: There are data suggesting a link between proton pump inhibitor (PPI) use and the development of spontaneous bacterial peritonitis (SBP) in cirrhotic patients with ascites; however, these data are controversial.
OBJECTIVE: To assess whether the use of PPIs in cirrhotic patients with ascites is associated with an increased risk for SBP.
METHODS: A retrospective case-control study (June 2004 to June 2010) was conducted at the Centre Hospitalier de l'Université de Montréal in Montreal, Quebec. Fifty-one cirrhotic patients admitted with paracentesis-proven SBP (≥250 neutrophils/mm3), occurring within seven days of hospital admission, met the inclusion criteria. These patients were matched 1:2 (for age, Child-Pugh class and year of admission) with 102 comparable cirrhotic patients with ascites who were admitted for conditions other than SBP.
RESULTS: Patients with SBP had a significantly higher rate of pre-hospital PPI use (60.8%) compared with cirrhotic patients without SBP (42.2%; P=0.03). On multivariate analysis, PPI use was the only factor independently associated with SBP (OR 2.09 [95% CI 1.04 to 4.23]; P=0.04). Thirty-five (35%) patients in both groups had no documented indication for PPI use in their charts. Forty-five percent of the remaining cirrhotic patients with SBP had an inappropriate indication, as defined in the protocol, for PPI use compared with 25% of controls.
CONCLUSIONS: Cirrhotic patients with SBP were twice as likely to have taken PPIs than patients without SBP. These findings reinforce the association between PPI use and SBP observed in other studies. A high percentage of cirrhotic patients were taking a PPI without any documented indication.