Under-reporting of gastrointestinal bleeding associated with anticoagulant use using the UK Yellow Card Scheme.

Background: The Yellow Card Scheme was created in 1964 to oversee new and existing medicines and medical devices, and act as an early warning system for unexpected adverse drug reactions (ADRs). Under-reporting within the system is a known issue, estimated to be as high as 94% in a 2006 systematic review. Anticoagulants are often prescribed in the UK to prevent stroke in patients with atrial fibrillation but can be associated with gastrointestinal bleeding as a common ADR.

Aim: The study aimed to investigate the incidence of suspected DOAC-related GI bleeds at a North-West England hospital and explore the volume of these incidents reported through the MHRA Yellow Card Scheme, over a 5-year period.

Method: Hospital coding data was used to identify patient records with GI bleeding and cross-referenced with electronic prescribing records for anticoagulant usage. Additionally, pharmacovigilance reporting activity for the Trust was obtained from the MHRA Yellow Card Scheme.

Results: For the period investigated, the Trust recorded 12,013 GI bleed related emergency admissions. Of these admissions, 1058 patients were taking a DOAC. During the same time period, a total of 6 DOAC-related pharmacovigilance reports were made by the trust.

Conclusion: Utilisation of the Yellow Card System for reporting potential ADR is poor, leading to under-reporting of ADRs.