Intervention Reduces Aspirin Use in Patients with AF, VTE Taking Warfarin, Improves Outcomes

A multicenter aspirin deprescribing intervention significantly decreased surplus aspirin use among sufferers dealt with with warfarin for atrial fibrillation (AF) and/or venous thromboembolism (VTE) who experienced no obvious indicator for concomitant antithrombotic treatment.

The “deimplementation” program was linked with a nearly 50% minimize in general aspirin use across 6 anticoagulation clinics which in flip was connected to noticeably less bleeding situations and a lower in health care use, devoid of an increase in thrombotic results.

Research authors, led by Geoffrey D. Barnes, MD, MSc, assistant professor, cardiovascular medication and vascular medicine, University of Michigan Wellness Procedure, publish that aspirin is appropriately put together with warfarin for some individuals with AF or VTE right after acute coronary syndromes or percutaneous coronary interventions, and also for some clients with mechanical coronary heart valves.

For most other individuals, however, the evidence implies better harm than good from the combination which boosts the danger for bleeding events without a very clear reduction in thrombotic outcomes, the authors add. Medical suggestions suggest versus the follow, but the investigators be aware that “many clients seem to be receiving aspirin even when the probable chance exceeds the benefit.”


For most other sufferers, however, the proof indicates bigger harm than excellent from the combination of aspirin and warfarin which will increase the threat for bleeding gatherings devoid of a crystal clear reduction in thrombotic outcomes.


Barnes et al utilized individual populations attending 6 scientific web-sites in the Michigan Anticoagulation High quality Improvement Initiative (MAQI) for the pre-publish observational high quality advancement review, assessing the pre- and postintervention proportion of individuals whose aspirin use appeared unclear as perfectly as the effects of the intervention on clinical outcomes.

Every single of the 6 MAQI clinics utilized a internet site-certain screening process to determine individuals receiving aspirin devoid of a apparent sign, collecting knowledge involving January 2010 and December 2019. The top quality enhancement interventions took place in between October 2017 and June 2018, in accordance to the review.

For these individuals whose indication for aspirin was unclear or appeared inappropriate, consultation with the patient’s most important care clinician or expert could trigger discontinuation.

The indications for aspirin use ended up assessed at enrollment for the pre-intervention cohort and assessed at enrollment or the initially comply with-up following implementation of the intervention for the publish-intervention cohort.

The MAQI adopted 6738 people determined as being handled with warfarin without having an indicator for aspirin (signify age, 62.8 yrs 46.9% gentlemen) for a median of 6.7 months. Extra than 50 % (55.1%) ended up obtaining anticoagulation for VTE.

Total, there was a just about 50% reduction in surplus aspirin use right after the deprescribing intervention, from a 29.4% to 15.7%.

Exclusively, details documented by Barnes and colleagues present a slight lower in use of aspirin across MAQI web sites from a baseline necessarily mean of 29.4% (95% CI, 28.9% – 29.9%) to 27.1% (95% CI, 26.1% – 28.%) throughout the 24-thirty day period preintervention period (P < .001 for slope before and after 24 months before the intervention).

Following the intervention, the decrease in aspirin use accelerated significantly to a mean of 15.7% (95% CI, 14.8% – 16.5%), a trajectory the authors point out was steeper than that seen during the preintervention period (P = .001 for slope before and after intervention).


Overall, there was a nearly 50% reduction in excess aspirin use after the deprescribing intervention, from 29.4% to 15.7%.


Results of primary analysis demonstrated a significant decrease in major bleeding events per month (preintervention, 0.31% 95% CI, 0.27%-0.34% postintervention, 0.21% 95% CI, 0.14%-0.28% P = .03 for difference in slope before and after intervention). Notably, there was no significant change from before to after the intervention in mean percentage of patients with a thrombotic event (0.21% vs 0.24% P = .34 for difference in slope).

In the secondary analysis, the research team found that reduced use of aspirin (starting 24 months prior to deprescribing intervention) was associated with decreases in mean percentage of patients:

  • having any bleeding event (2.3% vs 1.5% P = .02 for change in slope before and after 24 months before the intervention)
  • having a major bleeding event (0.31% vs 0.25% P = .001 for change in slope before and after 24 months before the intervention)
  • with an emergency department visit for bleeding (0.99% vs 0.67% P = .04 for change in slope before and after 24 months before the intervention)

“Our findings highlight the need for greater aspirin stewardship among patients receiving warfarin for anticoagulation,” wrote Barnes and colleagues, adding that the “successful intervention across multiple health systems, with different patient populations and clinical structures, could serve as a national model for reducing excess aspirin use.”

“Given that aspirin is not a prescription medication, it could be postulated that clinicians may not always be aware that patients are taking aspirin, which is a barrier to aspirin-deprescribing efforts,” they add.

They call for additional research to determine whether deprescribing aspirin for patients receiving newer direct oral anticoagulants is similarly effective as well as to confirm the current findings, “ideally with a control group.”


Reference: Schaefer JK, Errickson J, Gu X, et al. Assessment of an intervention to reduce aspirin prescribing for patients receiving warfarin for anticoagulation. JAMA Netw Open. 20225(9):e2231973. doi:10.1001/jamanetworkopen.2022.31973


By Percy