Drugs associated with posterior reversible encephalopathy syndrome, a worldwide signal detection study

Background: Posterior reversible encephalopathy syndrome (PRES) can occur in a variety of clinical conditions, such as severe hypertension, pregnancy, inflammatory diseases, hematopoietic stem cells or solid organ transplantation. Apart increased blood pressure levels and altered renal function, several drugs have been reported as potential triggering factor. These descriptions are nevertheless limited to case reports or small case series. Systematic analysis of drugs associated with PRES using global pharmacovigilance database is lacking and can be useful.

Methods: We performed a disproportionality analysis using VigiBase, the World Health Organization pharmacovigilance database, using the information component (IC). The IC compares observed and expected values to find associations between drugs and PRES using disproportionate Bayesian reporting. An IC_0.25 (lower end of the IC 95% credibility interval) > 0 is considered statistically significant.

Results: Here we present an analysis of 3278 cases of PRES reported in VigiBase. These results identified 73 molecules statistically associated with PRES using full database as background with an IC_0.25 > 0. Only 34% (N = 25/73) of them had this information written in the summary of product characteristics. The main drug classes involved were antineoplastic and immunomodulating agents and the drugs with the greatest number of cases were tacrolimus, cyclosporin, bevacizumab, methotrexate, and vincristine. An overall mortality of 8.1% (N = 267/3278) was identified in cases of drug-associated PRES.

Conclusion: These results will help clinicians identify potential suspected drugs associated with PRES and decide which drug to discontinue and eventually lead to a re-evaluation of drug labels for some molecules.