Indication of Acid Suppression Therapy and Predictors for the Prophylactic Use of Protonpump Inhibitors Vs. Histamine-2 Receptor Antagonists in a Malaysian Tertiary Hospital

Background: Proton-pump inhibitors (PPI) and histamine-2 receptor antagonists (H2RA) are common acid suppressants used in gastrointestinal disorders. The trend of usage in Malaysia has changed from predominantly H2RA to PPI from 2007 to 2008, 3.46 versus 2.87 and 2.99 versus 3.24 DDD (Defined Daily Dose)/1000 population/day respectively. This raises concerns as PPI overutilization amounts to higher cost expenditure and are associated with various untoward consequences such as Clostridium difficile-associated diarrhea, pneumonia, and osteoporosis.

Objectives: To evaluate the indication of acid suppression therapy (AST) and to look for predictors associated with the prophylactic use of PPI as compared to H2RA.

Methods: Data collection was conducted via a standardized surveillance form over a 2-month period in the general medical wards of Sarawak General Hospital. All patients who received at least one dose of PPI or H2RA in any dosage form were included in the study. Appropriateness of prophylaxis was determined using current available guidelines. Selected risk factors were analysed using simple logistic regression to look for predictors associated with the choice of PPI in prophylactic AST.

Results: Out of 212 cases in the present cohort, about three quarters (75.5%, n=160) of acid suppressants were given as prophylaxis. Over half of these did not have appropriate indications for prophylactic AST (58.1%, n=93). Among all cases given prophylactic AST, 75.0% (n=120) of them were given PPI. Renal insufficiency was identified as the only predictor associated with the use of prophylactic PPI in preference to H2RA (OR=2.86, 95%CI 1.21:6.72, p=0.011).

Conclusion: Inappropriate prophylactic AST is a major concern and may even be underestimated due to the lack of appropriate guidelines. More data is required to guide the selection between PPI and H2RA, specifically the more cost-effective use of H2RA in patients with lower gastrointestinal risk or in whom PPI has no clear advantage.