Long-term PPI use does not increase gastric cancer risk

Use of proton pump inhibitors (PPIs) in the long term, as compared to histamine 2 receptor antagonists (H2RAs), does not lead to a higher risk of gastric cancer even in a high-risk region, results of a large study have shown.

“PPIs are commonly prescribed medications,” the researchers said. “Long-term use of PPIs has been suspected to have a provocative effect on gastric cancer.”

To determine whether PPI vs H2RA use correlated with the risk of gastric cancer in a region where the risk was high, this population-based cohort study was carried out with the use of the Korean National Health Insurance Services Database.

The researchers enrolled participants with first prescription of PPIs and H2RAs with normal oesophagogastroduodenoscopy finding from 2004 through 2005, among whom half (50 percent) were sampled in a systematically stratified random way.

A total of 122,118 participants on PPIs or H2RAs used the medication more than the cumulative defined daily dose of 180 days. Users were then followed from long-term use threshold until gastric cancer, death from nongastric cancer cause, gastric surgery, or study end (December 2017).

After calculating for propensity score weights, 39,799 PPI and 38,967 H2RA users were included. Among new users, 411 and 397 cases of incident gastric cancer were identified from 182,643 and 178,846 person-years of follow-up observation, respectively.

Of note, PPI users did not experience a significantly increased incidence of gastric cancer relative to H2RA users (adjusted hazard ratio, 1.01, 95 percent confidence interval, 0.88–1.16; p=0.89). No between-group difference was also noted in gastric cancer incidence in sensitivity analyses.