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Published on: October 12, 2012
Signal detection for bleeding associated with the use of direct oral anticoagulants
Kobi T Nathan1, Kelly M Conn2, Robbert P van Manen3
1Department of Pharmacy Practice, St. John Fisher College, Rochester, NY knathan@sjfc.edu.
Insights
Direct oral anticoagulants (DOACs) show a potential link to serious or life-threatening bleeding events. This analysis of adverse event reports suggests a quantitative signal for increased bleeding risk with DOAC use.
Area of Science:
- Pharmacovigilance
- Clinical Pharmacology
- Drug Safety
Background:
- Direct oral anticoagulants (DOACs) are increasingly used for anticoagulation.
- Concerns exist regarding their safety profile, particularly bleeding risks.
- Comparative safety data, especially for serious bleeding, requires ongoing evaluation.
Purpose of the Study:
- To evaluate the potential association between direct oral anticoagulants (DOACs) and serious or life-threatening bleeding events.
- To compare bleeding event profiles of DOACs with warfarin.
- To identify specific bleeding event types associated with DOAC use.
Main Methods:
- A disproportionality analysis using an empirical Bayesian approach was conducted on Food and Drug Administration Adverse Event Reporting System (FAERS) data.
- Case reports of bleeding events involving dabigatran, rivaroxaban, apixaban, edoxaban, and warfarin were reviewed up to March 31, 2017.
- Subanalyses focused on bleeding events, including mortality and life-threatening events, and warfarin-related bleeding.
Main Results:
- 35 adverse event terms with a disproportionality score >7.5 were identified for DOACs, totaling 40,109 reports.
- High disproportionality scores were observed for atrial thrombosis, pericardial hemorrhage, and internal hemorrhage.
- Hemorrhage (6,881 events), internal hemorrhage (2,569), and hematoma (1,995) were the most frequent DOAC-associated bleeding events. Warfarin had 8,729 adverse events, with hemorrhage (6,225) being most common.
Conclusions:
- Disproportionality analysis of FAERS data indicates a quantitative signal linking DOAC use to serious or life-threatening bleeding.
- This finding underscores the importance of monitoring for bleeding events in patients treated with DOACs.
- Further research may be warranted to elucidate the mechanisms and clinical implications of these bleeding risks.
Purpose:
The potential link between serious or life-threatening bleeding and the use of direct oral anticoagulants (DOACs) was evaluated.
Methods:
Qualitative and quantitative reviews of case reports of bleeding events involving dabigatran, rivaroxaban, apixaban, edoxaban, and warfarin through March 31, 2017, were performed. A disproportionality analysis was conducted for each DOAC using an empirical Bayesian approach based on the relative reporting rate. Subanalyses were performed to assess (1) bleeding events (including mortality and life-threatening events) associated with DOACs among all adverse-event reports and (2) warfarin-related bleeding events. These analyses were conducted based on clinical definitions from the Medical Dictionary for Regulatory Activities.
Results:
During the Food and Drug Administration Adverse Event Reporting System (FAERS) review period, 35 adverse-event terms (in any system organ class) with a disproportionality score (EB05) of >7.5 for DOACs were identified; this accounted for 40,109 adverse-event reports. Adverse events with the highest disproportionality scores included atrial thrombosis, increased factor X level, dysfunctional uterine bleeding, high-frequency ablation, pericardial hemorrhage, and internal hemorrhage. Adverse events with the highest EB05 (>5) included internal hemorrhage, hemorrhage, and exsanguination; events with the greatest number of patient experiences included hemorrhage (6,881 events), internal hemorrhage (2,569 events), and hematoma (1,995 events). Warfarin-related events (including death or life-threatening events) were also assessed. A total of 8,729 adverse events were associated with warfarin use. The most common of these included hemorrhage (6,225 events), hematoma (2,199 events), and internal hemorrhage (270 events).
Conclusion:
The disproportionality analysis of the FAERS database suggests a quantitative signal between DOAC use and life-threatening or serious bleeding.
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