Intracranial bleeds occurred less frequently among renally impaired ED admitted patients prescribed DOACs compared with vitamin K antagonists.
Anticoagulant-associated bleeding is a common and potentially serious problem for patients. Direct oral anticoagulants (DOACs) such as apixaban, dabigatran and rivaroxaban are now being increasingly used instead of vitamin K antagonists (VKA) such as warfarin. This change is largely due to the emerging evidence indicating beneficial effects from DOACs such as a lower incidence of bleeding. For example, a 2014 meta-analysis concluded that in comparison with warfarin, DOACs were associated with significant reduction in all-cause mortality and intracranial bleeds but there was an increased incidence of gastrointestinal bleeding. An additional problem for DOACs comes from a study in elderly patients that highlighted how major bleeding episodes in those prescribed DOACs were associated with a decline in renal function based on a reduction in glomerular filtration rate (GFR).
But are there important differences in the bleeding characteristics of patients with impaired kidney function, admitted to an emergency department (ED) due to an acute haemorrhage? This was the question addressed by a team from the Department of Emergency Medicine, University Hospital, Bern, Switzerland. They performed a retrospective study over a four year period, of patients treated at the ED for an acute haemorrhage prescribed either a DOAC or VKA and with impaired kidney function, defined as a GFR < 60 ml/min. The team compared the areas affected by bleeding e.g., intracranial or gastrointestinal etc, by drug class (i.e., DOAC or VKA) and several other relevant outcomes such as the length of hospital stay and the need for intensive care unit admission.
The initial database search identified 14,684 patients though after exclusions, mainly due to no GFR data, evidence of no bleeding or irregular consultation documentation, 158 patients prescribed a DOAC and 419 VKA were included in the analysis. The overall median age of patients was 79 years (56.7% male) and the renal function of VKA patients was significantly worse compared to those prescribed DOACs (creatinine levels, 132 vs 141 DOAC vs VKA, p = 0.002). Moreover, there was a higher number of intracranial bleeds in the VKA group (22.4% vs 14.6%, VKA vs DOACs, p = 0.036), but there were no differences for other sites. The most common site for a bleed was the gastrointestinal tract (34.8% vs 28.6%, DOAC vs VKA). Although DOAC patients required a higher number of emergency endoscopies (15.8% vs 9.1%, DOAC vs VKA, p = 0.020), VKA patients required a higher number of interventions to stop the bleeding compared to DOAC (22.2% vs. 13.9%, p = 0.027).
Most patients were treated in hospital (92.4% DOAC vs 90.2% VKA, p = 0.431) and a higher proportion of VKA patients were admitted to intensive care (38.2% vs 43.4%, DOAC vs VKA). However, overall, there were no differences in the length of hospital stay.
The authors concluded that among ED admissions due to an acute haemorrhage in patients prescribed anticoagulants and with impaired renal function, those taking DOACs had a lower incidence of intracranial bleeds.
Muller M et al. Impaired kidney function at ED admission: a comparison of bleeding complications of patients with different oral anticoagulants. BMC Emerg Med 2021