Prophylactic Use of Acid-Suppressive Drugs to Prevent Nosocomial GI Bleeding

A retrospective study found that although acid-suppressive medication reduces the risk of nosocomial (hospital-acquired) bleeding from the gastrointestinal (GI) tract in noncritical hospitalized patients, using these drugs routinely as prophylaxis prevents too few cases to justify the expense [Arch Intern Med. 2011;171(11):991-997]. Based on earlier studies supporting prophylactic use of acid-suppressive medications in patients admitted to the intensive care unit (ICU), hospitals have increasingly expanded the practice to include noncritical patients, in conflict with current American Society of Health-System Pharmacists (ASHP) guidelines. ASHP based its ruling on the lack of evidence supporting the practice, and the authors said data from their study lend validity to the recommendation. Medical charts and other data were reviewed for 78,394 adults hospitalized over a 3-year period at a large medical center in Boston, Massachusetts, for ≥3 days. The patients ranged from 18 to 107 years in age (median, 56 years), and 41% were men; records showed no evidence of GI bleeding on admission. An acid-suppressive medication was administered to 59% of patients (n=45,882). The majority (81%; n=37,392) received a proton pump inhibitor, and the remaining 29% (n=13,194) were given a histamine-2 receptor antagonist. Of the patients enrolled in the study, 0.29% (n=224) developed nosocomial bleeding of the upper GI tract >24 hours after admission. In 0.22% (n=176) of cases, bleeding was considered significant, as indicated by an International Classification of Diseases, Ninth Revision, Clinical Modification code in the chart for upper endoscopy and administration of ≥2 units of packed red blood cells. An initial analysis found patients treated with acid-suppressive medications were more likely to develop nosocomial GI bleeding than untreated patients (0.33% vs 0.22%, respectively) and had a higher incidence of significant bleeding (0.26% vs 0.18%, respectively). Because baseline characteristics varied greatly between the 2 cohorts, investigators matched 18,983 patients from each study arm who had similar baseline characteristics and conducted an adjusted analysis. They found the same overall incidence of GI bleeding (0.29%; n=224), but, in contrast with the unadjusted analysis, the matched patients given an acid-suppressive medication were significantly less likely to experience a nosocomial GI bleed (odds ratio [OR], 0.63; 95% confidence interval [CI], 0.42-0.93) and had a lower risk of clinically significant GI bleeding (OR, 0.58; 95% CI, 0.37-0.91). Extrapolating from these data, researchers said 770 patients would need to receive prophylactic acid-suppressive medication to prevent 1 case of nosocomial GI bleeding. Preventing 1 episode of significant nosocomial GI bleeding would require treating 834 patients. A subgroup analysis comparing the rate of GI bleeding in the cohort of acid-suppressive users overall with the rate of patients who used a proton inhibitor revealed little difference (OR, 0.58; 95% CI, 0.41-0.84). The investigators noted that nosocomial GI bleeding was a rare event in this large study comprising noncritically ill patients. Although it was 37% less likely to occur in patients taking acid-suppressive medications, too many patients would need to be treated to prevent 1 case to justify using these agents routinely outside the ICU. According to the authors, the fact that physicians are more apt to give acid-suppressive medications to patients at higher risk for GI bleeding probably explains the higher rate of nosocomial GI bleeding observed in the medicated cohort per the unadjusted analysis. They proposed that the adjusted analysis sufficiently controlled for confounding factors, as evidenced by the fact that the adjusted OR is consistent with trials investigating the effects of acid-suppressive drug use in ICU patients. “Our findings support the current recommendations against routine use of prophylactic acid-suppressive medication in patients outside of the ICU,” the researchers said.