Thiopurines do not exacerbate risk of post-ERC pancreatitis

In patients with primary sclerosing cholangitis (PSC), past or present use of thiopurines does not increase the risk of post-endoscopic retrograde cholangiography (ERC) pancreatitis (PEP), a recent study has found.

The study included 971 PSC patients (median age 39 years, 43.8 percent women) who had undergone a total of 985 ERCs between 2009 and 2018. Thiopurine use was documented in 177 patients; after propensity-score matching, a control group of 177 patients without thiopurine history was also included in the analysis.

After matching, 472 and 513 ERC procedures were available for analysis in the thiopurine and control groups, leading to 25 and 29 cases of PEP, respectively. The corresponding incidence rates were 5.3 percent and 5.7 percent (p=0.889). In the thiopurine use, comparing procedures with vs without thiopurine use led to respective PEP incidence rates of 4.8 percent and 7.1 percent (p=0.447).

Other adverse events likewise occurred comparably between thiopurine users and controls, including cholangitis (p=0.457), bleeding (p=0.052), and perforation (p=1.00).

Multivariable analysis further confirmed that thiopurine use had no significant impact on the risk of PEP, both when assessed using a generalized linear mixed model (odds ratio [OR], 0.97, 95 percent confidence interval [CI], 0.32–2.87; p=0.951) or a logistic regression model (OR, 0.98, 95 percent CI, 0.35–2.73; p=0.962).

“We found no difference in the PEP rate between PSC patients with and without thiopurine use. In addition, no connection between prior or present use of thiopurines and the PEP risk was found,” the researchers said.