Recommendations for Research Assessing Outcomes for Patients With Anticoagulant-Related Intracerebral Bleeds

[Correction of the effect of direct oral and parenteral anticoagulants in hemorrhagic stroke]

BACKGROUND

Hemorrhagic stroke is associated with high risk of adverse outcome and follows intake of anticoagulants and antiplatelet agents in 25% of cases. The latest clinical guidelines of the Neurocritical Care Society for correction (reversal) of the effect of anticoagulants and antiplatelet agents in hemorrhagic stroke were published in 2016.

MATERIAL AND METHODS

In accordance with PRISMA recommendations, we reviewed the PubMed, eLibrary and UpToDate databases to a depth of 5 years and selected 48 articles.

RESULTS AND DISCUSSION

Direct oral anticoagulants are currently common. To reverse their effect, one can use specific antidotes (idarucizumab is recommended for dabigatran, andexanet alfa (not yet registered In Russia) for factor Xa inhibitors (rivaroxaban, apixaban)) and combination of prothrombin complex concentrate and tranexamic acid. Protamine sulfate is antidote for unfractionated and low molecular weight heparins. Protamine sulfate completely inactivates unfractionated heparin, but it is less effective against low molecular weight heparin. It is characterized by high probability of anaphylactic reactions, especially after repeated administrations. The effectiveness of andexanet alpha and activated factor VII for reversing the effect of low molecular weight heparin is being studied. Fondaparinux sodium is used for heparin-induced thrombocytopenia. Protamine sulfate is ineffective for reversing the effect of fondaparinux. One can use prothrombin complex concentrate and andexanet alpha, but their effectiveness is unclear. Ciraparantag is being studied in clinical trials. Apparently, ciraparantag is highly effective as an antidote for various anticoagulants.

CONCLUSION

Early hemostatic therapy and reversal of anticoagulant effects in patients with hemorrhagic stroke significantly reduce the risk of adverse outcomes. This problem is being studied. Regular literature review with creation of updated clinical guidelines is needed.

Association of Prior Antithrombotic Drug Use with 90-Day Mortality After Intracerebral Hemorrhage

Purpose

To estimate the strength of association between use of antithrombotics (AT) drugs with survival after spontaneous intracerebral hemorrhage (s-ICH) comparing oral anticoagulant (OAC) or platelet antiaggregants (PA) with no AT use and in active comparator analyses OAC vs PA, direct oral anticoagulant (DOAC) vs vitamin K antagonist (VKA), and clopidogrel vs aspirin.

Patients and Methods

We identified patients ≥55 years with a first-ever s-ICH between 2015 and 2018 in Southern Denmark (population 1.2 million). From this population, patients who had used an AT at the time of ICH were identified and classified as OAC or PA vs no AT (reference group), and for active comparator analyses as OAC vs PA (reference group), DOAC vs VKA (reference group), or clopidogrel vs aspirin (reference group). We calculated adjusted relative risks (aRRs) and corresponding [95% confidence intervals] for 90-day all-cause mortality with adjustments for potential confounders.

Results

Among 1043 patients who had s-ICH, 206 had used an OAC, 270 a PA, and 428 had no AT use. The adjusted 90-day mortality was higher in OAC- (aRR 1.68 [1.39-2.02]) and PA-users (aRR 1.21 [1.03-1.42]), compared with no AT. Mortality was higher in OAC- (aRR 1.19 [1.05-1.36]) vs PA-users. In analyses by antithrombotic drug type, 88 used a DOAC, 136 a VKA, 111 clopidogrel, and 177 aspirin. Mortality was lower among DOAC- vs VKA-users (aRR 0.82 [0.68-0.99]), but similar between clopidogrel vs aspirin users (aRR 1.04 [0.87-1.24]).

Conclusion

In this unselected cohort from a geographically defined Danish population, 90-day mortality after s-ICH was higher in patients with prior use of an OAC compared with no AT use or patients using a PA. Mortality was slightly lower for patients using a DOAC than a VKA. Mortality was also higher in PA- vs no AT-users, but there were no differences in mortality between clopidogrel vs aspirin.

Agreement between 30-day and 90-day modified Rankin Scale score and utility-weighted modified Rankin Scale score in acute intracerebral hemorrhage: An analysis of ATACH-2 trial data

The relationship between 30- and 90-day modified Rankin Scale (mRS) scores in intracerebral hemorrhage (ICH) patients was evaluated. This post hoc cohort analysis of the ATACH-2 trial included patients with acute ICH who were alive at 30 days and who had mRS scores reported at 30 and 90 days. The mRS score was then converted to a utility (EuroQol-5 Dimension-3 Level [EQ-5D-3L])-weighted mRS score. After adjustment of 30-day mRS score for key covariates using multivariable ordinal regression, the relationship between 30-day and observed 90-day functional outcome was assessed via absolute difference in the utility-weighted version. Of the 1000 trial subjects, 898 met inclusion criteria. This low-moderate severity ICH cohort had a median baseline GCS score of 15 and median hematoma volume of 9.7 mL. Observed 30-day mRS had the largest association with observed 90-day values (χ2 = 302.9, p < 0.0001). Patients generally either maintained the same mRS scores between 30 and 90 days (48 %) or experienced a 1-point (32 %) or 2-point (10 %) improvement by 90 days. The mean ± standard deviation (SD) EQ-5D-3L at 90 days was 0.67 ± 0.26. Following adjustment, the mean absolute difference between predicted and observed utility-weighted 90-day mRS scores was 0.006 ± 0.13 points and less than the estimated minimal clinically important difference of 0.13 points. The difference in average utility-weighted mRS scores at 30 and 90 days was not clinically relevant, suggesting 30-day score may be a reasonable proxy for 90-day values in patients with ICH when 90-day values are not available.

[Correction of the effect of vitamin K antagonists and antiplatelet agents in hemorrhagic stroke]

BACKGROUND

Hemorrhagic stroke (HS) is associated with high risk of mortality or disability. To date, up to 25% of HSs are associated with anticoagulants and antiplatelet agents. Early hemostatic therapy and correction of effect of antithrombotic drugs in patients with HS significantly reduce the risk of adverse outcomes. The latest international guidelines on this issue were presented almost 10 years ago.

MATERIAL AND METHODS

In accordance with the PRISMA recommendations, we reviewed the PubMed, eLibrary and UpToDate databases and identified 137 articles. Of these, 52 were enrolled as the most relevant.

RESULTS AND DISCUSSION

Regarding correction of the effect of indirect anticoagulants, various researchers discuss the possibility of either individual dosing or injection of a fixed dose of 4- or 3-factor prothrombin complex (1000-2000 IU regardless of body weight and international normalized ratio). To correct the effect of antiplatelet agents, platelet transfusion and desmopressin are proposed. There is currently no evidence of safety and effectiveness of both methods in patients with HS.

CONCLUSION

The optimal drug for correction of the effect of indirect anticoagulants is 4- or 3-factor prothrombin complex. In the last case, it is necessary to administer factor VIIa or fresh frozen plasma, as well as parenteral form of phytomenadione (vitamin K1) in all cases. The issue of correction of the effects of antiplatelet agents remains open. Regular analysis of available data with updating the guidelines for correction of the effect of anticoagulants and antiplatelet agents in HS is necessary.

Lower mortality with andexanet alfa vs 4-factor prothrombin complex concentrate for factor Xa inhibitor-related major bleeding in a U.S. hospital-based observational study

Background

Well-designed studies with sufficient sample size comparing andexanet alfa vs 4-factor prothrombin complex concentrate (4F-PCC) in routine clinical practice to evaluate clinical outcomes are limited.

Objectives

To compare in-hospital mortality in patients hospitalized with rivaroxaban- or apixaban-related major bleeding who were treated with andexanet alfa or 4F-PCC.

Methods

An observational cohort study (ClinicalTrials.gov identifier: NCT05548777) was conducted using electronic health records between May 2018 and September 2022 from 354 U.S. hospitals. Inclusion criteria were age ≥18 years, inpatient admission with diagnosis code D68.32 (bleeding due to extrinsic anticoagulation), a record of use of the factor Xa inhibitors rivaroxaban or apixaban, andexanet alfa or 4F-PCC treatment during index hospitalization, and a documented discharge disposition. Multivariable logistic regression on in-hospital mortality with andexanet alfa vs 4F-PCC was performed. The robustness of the results was assessed via a supportive propensity score-weighted logistic regression.

Results

The analysis included 4395 patients (andexanet alfa, n = 2122; 4F-PCC, n = 2273). There were 1328 patients with intracranial hemorrhage (ICH), 2567 with gastrointestinal (GI) bleeds, and 500 with critical compartment or other bleed types. In the multivariable analysis, odds of in-hospital mortality were 50% lower for andexanet alfa vs 4F-PCC (odds ratio [OR], 0.50; 95% CI, 0.39-0.65; P < .01) and were consistent for both ICH (OR, 0.55; [0.39-0.76]; P < .01) and GI bleeds (OR, 0.49 [0.29-0.81]; P = .01). Similar results were obtained from the supporting propensity score-weighted logistic regression analyses.

Conclusion

In this large observational study, treatment with andexanet alfa in patients hospitalized with rivaroxaban- or apixaban-related major bleeds was associated with 50% lower odds of in-hospital mortality than 4F-PCC. The magnitude of the risk reduction was similar in ICH and GI bleeds.

Recommended Primary Outcomes for Clinical Trials Evaluating Hemostatic Agents in Patients With Intracranial Hemorrhage: A Consensus Statement

IMPORTANCE

In patients with acute spontaneous or traumatic intracranial hemorrhage, early hemostasis is thought to be critical to minimize ongoing bleeding. However, research evaluating hemostatic therapies has been hampered by a lack of standardized clinical trial outcome measures.

OBJECTIVE

To identify appropriate primary outcomes for phase 2 and 3 clinical trials of therapies aimed at reducing acute intracranial bleeding.

EVIDENCE REVIEW

A comprehensive review of all previous clinical trials of hemostatic therapy for intracranial bleeding was performed, and studies measuring the frequency, risk factors, and association of intracranial bleeding with outcome of hemorrhage growth were included.

FINDINGS

A hierarchy of 3 outcome measures is recommended, with the first choice being a global patient-centered clinical outcome scale measured 30 to 180 days after the event; the second, a combined clinical and radiographic end point associating hemorrhage expansion with a poor patient-centered outcome at 24 hours or later; and the third, a radiographic measure of hemorrhage expansion at 24 hours alone. Additional recommendations stress the importance of separating various subtypes of bleeding when possible, early treatment within a standardized treatment window, and the routine use of computerized planimetry comparing continuous measures of absolute and relative hemorrhage growth as either a primary or secondary end point.

CONCLUSIONS AND RELEVANCE

Standardization of outcome measures in studies of intracranial bleeding and hemostatic therapy will support comparative effectiveness research and meta-analysis, with the goal of accelerating the translation of research into clinical practice. The 3 outcome measures proposed in this consensus statement could help this process.