H2 blockers prevented clinically important GI bleeding better than PPIs in ICU patients

The retrospective study included 70,093 ICU patients who had at least one risk factor for stress ulcers and therefore had received a proton-pump inhibitor (PPI) or histamine H2-receptor antagonist (H2 blocker) for three or more days.


For stress-ulcer prophylaxis in critically ill adults, histamine H2-receptor antagonists (H2 blockers) are associated with a significantly lower risk of clinically important gastrointestinal (GI) bleeding than proton-pump inhibitors (PPIs), a recent study found.

Researchers retrospectively assessed clinically important GI bleeding episodes in 70,093 patients who had at least one risk factor for stress ulcers and had received a PPI or H2 blocker for three or more days between Jan. 1, 2008, and June 30, 2012. Risk factors included mechanical ventilation for more than 24 hours, coagulopathy, head injuries, major burns, sepsis, corticosteroid therapy (≥250 mg of hydrocortisone per day or equivalent), acute renal failure, hepatic failure, transplantation, neurological injuries, hypotension, surgery, trauma, or ICU length of stay greater than one week. Episodes of clinically important GI bleeding were defined by one entry of the ICD-9 code that included hematemesis, blood in stool, and unspecified bleeding.

Overall, 49,576 (70.7%) patients received PPIs and 20,517 (29.3%) patients received H2 blockers. The most common risk factor for stress ulcers was mechanical ventilation (60%), and more than 50% of patients received anticoagulants, antiplatelets, or NSAIDs during their ICU stay. There were 424 (0.6%) cases of new clinically important GI bleeding in the cohort, which yielded an incidence rate of 1.2 cases per 1,000 patient-days (95% CI, 1.08 to 1.31). After adjustment for potential confounders, the PPI group had a nearly twofold higher risk of clinically important GI bleeding than the H2 blocker group (hazard ratio, 1.97; 95% CI, 1.48 to 2.63).

Other factors associated with a higher risk of GI bleeding included male gender (hazard ratio [HR], 1.27; 95% CI, 1.04 to 1.54), acute renal failure (HR, 1.59; 95% CI, 1.28 to 1.97), receipt of sucralfate (HR, 3.25; 95% CI, 2.18 to 4.85), and receipt of an antiplatelet agent (HR, 1.35; 95% CI, 1.01 to 1.79). Having a surgical procedure or being a trauma victim was associated with a lower risk of clinically important GI bleeding (HR, 0.46; 95% CI, 0.25 to 0.84). The study was published online on May 29 by CHEST.

The study authors noted limitations, such as the fact that exposure to PPIs or H2 blockers was not randomly assigned and that confounding factors related to the tendency of an ICU to preferentially prescribe a PPI may have been present. Despite these limitations, the findings “support the conclusions of cost-effectiveness studies that favor the use of [an H2 blocker] over a PPI for stress ulcer prophylaxis of at risk critically ill adults,” they concluded.