Comparison of the effects of diclofenac or other non-steroidal anti-inflammatory drugs (NSAIDs) and diclofenac or other NSAIDs in combination with proton pump inhibitors (PPI) on hospitalisation due to peptic ulcer disease.

Purpose: Up to 25% of patients taking non-steroidal anti-inflammatory drugs (NSAIDs) chronically experience gastrointestinal side effects. This report aims to determine the gastroprotective effects of proton pump inhibitors (PPI) in patients taking NSAIDs, especially diclofenac.

Methods: From the claims database of a German sickness fund with 1.4 million beneficiaries, we used data from patients enrolled in the health plan continuously from 2000 until 2004 with an inpatient diagnosis of peptic ulcer disease in 2003 and 2004. For our nested case-control study, we matched these cases for calendar time with up to 10 controls per case. Our main outcome measure were the adjusted odds ratios (ORs) for peptic ulcer disease associated with diclofenac and other NSAIDs.

Results: In the study population of 752 613 beneficiaries, 979 cases and 10 319 controls were identified. A stratified analysis according to the prescription of diclofenac alone or in combination with PPI showed that diclofenac prescriptions increased the risk for hospitalisation due to peptic ulcer significantly (adjusted OR 2.4 [95%CI 1.94, 3.05]). If PPI were prescribed concomitantly with diclofenac, we observed a risk reduction (OR 1.3 [95%CI 0.7, 2.3]). The significance of the PPI effect was shown using an interaction term in a regression model without stratification, where a risk reduction of 60% (OR 0.4 [95%CI 0.2, 0.7], p < 0.05) was found.

Conclusions: The concomitant prescription of PPI and diclofenac decreases the hospitalisation risk due to peptic ulcer significantly. The results support the use of PPI as gastroprotective agents in patients who receive NSAIDs.