The Intracranial-B2LEED3S Score and the Risk of Intracranial Hemorrhage in Ischemic Stroke Patients Under Antiplatelet Treatment

A new score for predicting intracranial hemorrhage in patients using antiplatelet drugs

Antiplatelet drugs in patients increase the risk of intracranial hemorrhage (ICH), which can seriously affect patients' quality of life and even endanger their lives. Currently, there is no specific score for predicting the risk of ICH caused by antiplatelet drugs. We aimed to identify factors associated with ICH in patients on antiplatelet drugs and to construct and validate a predictive model that would provide a validated tool for the clinic. Data were obtained from the patient medical records inpatient system. Prediction models were built by logistic regression, the area under the curve (AUC), and column line plots. Internal validation, analytical identification and calibration of the model using AUC, calibration curves and Hosmer-Lemeshow test. The registration number of this study is ChiCTR2000031909, and the ethical review number is 2020KY087. This single-center retrospective study enrolled 753 patients treated with antiplatelet drugs, including 527 in the development cohort. Multifactorial analysis showed that male, headache or vomiting, hypertension, cerebrovascular disease, CT-defined white matter hypodensity, abnormal GCS, fibrinogen and D-dimer were independent risk factors for ICH, and lipid-lowering drugs was a protective factor. The model was constructed using these nine factors with an AUC value of 0.949. In the validation cohort, the model showed good discriminatory power with an AUC value of 0.943 and good calibration (Hosmer-Lemeshow test P value of 0.818). Based on 9 factors, we derived and validated a predictive model for ICH with antiplatelet drugs in patients. The model has good predictive value and may be an effective tool to reduce the occurrence of ICH.

Bleeding with intensive versus guideline antiplatelet therapy in acute cerebral ischaemia

Intensive antiplatelet therapy did not reduce recurrent stroke/transient ischaemic attack (TIA) events as compared with guideline treatment in the Triple Antiplatelets for Reducing Dependency after Ischaemic Stroke (TARDIS) trial, but did increase the frequency and severity of bleeding. In this pre-specified analysis, we investigated predictors of bleeding and the association of bleeding with outcome. TARDIS was an international prospective randomised open-label blinded-endpoint trial in participants with ischaemic stroke or TIA within 48 h of onset. Participants were randomised to 30 days of intensive antiplatelet therapy (aspirin, clopidogrel, dipyridamole) or guideline-based therapy (either clopidogrel alone or combined aspirin and dipyridamole). Bleeding was defined using the International Society on Thrombosis and Haemostasis five-level ordered categorical scale: fatal, major, moderate, minor, none. Of 3,096 participants, bleeding severity was: fatal 0.4%, major 1.5%, moderate 1.2%, minor 11.4%, none 85.5%. Major/fatal bleeding was increased with intensive as compared with guideline therapy: 39 vs. 17 participants, adjusted hazard ratio 2.21, 95% CI 1.24-3.93, p = 0.007. Bleeding events diverged between treatment groups in the 8-35 day period but not in the 0-7 or 36-90 day epochs. In multivariate analysis more, and more severe, bleeding events were seen with increasing age, female sex, pre-morbid dependency, increased time to randomisation, prior major bleed, prior antiplatelet therapy and in those randomised to triple vs guideline antiplatelet therapy. More severe bleeding was associated with worse clinical outcomes across multiple physical, emotional and quality of life domains.Trial registration ISRCTN47823388 .

External validation of bleeding risk models for the prediction of long-term bleeding risk in patients with established cardiovascular disease

OBJECTIVE

The long-term predictive performance of existing bleeding risk models in patients with various manifestations of cardiovascular disease (CVD) is not well known. This study aims to assess and compare the performance of relevant existing bleeding risk models in estimating the long-term risk of major bleeding in a cohort of patients with established CVD.

METHODS

Seven existing bleeding risk models (PRECISE-DAPT, DAPT, Ducrocq et al, de Vries et al, S₂TOP-BLEED, Intracranial B₂LEED₃S and HAS-BLED) were identified and externally validated in 7,249 patients with established CVD included in the Utrecht Cardiovascular Cohort-second manifestations of arterial disease study. Predictive performance was assessed in terms of discrimination and calibration, both at 10 years and the original prediction horizon of the models. Major bleeding was defined as Bleeding Academic Research Consortium type 3 or 5.

RESULTS

After a median follow-up of 8.4 years (interquartile range 4.5-12.5), a total of 233 (3.2%) major bleeding events occurred. C-statistics for discrimination at 10 years ranged from 0.53 (95%CI 0.49-0.57) to 0.64 (95%CI 0.60-0.68). Calibration plots after recalibration to 10 years showed best agreement between predicted and observed bleeding risk for De Vries et al, S₂TOP-BLEED, DAPT and PRECISE-DAPT.

CONCLUSIONS

The performance of existing bleeding risk models to predict long-term bleeding in patients with CVD varied. Discrimination and calibration were best for the models of de Vries et al, S₂TOP-BLEED, DAPT and PRECISE-DAPT. Of these, recalibrated models requiring the least predictors may be preferred for use to personalize prevention with antithrombotic therapy.

PROK2, HRNR, and FIG4 as potential genetic biomarkers of high bleeding propensity in East Asian patients with acute coronary syndrome using ticagrelor

STUDY OBJECTIVE

East Asians have a higher risk of bleeding than Europeans when treated with ticagrelor. This study aimed to explore genetic indicators related to the high bleeding propensity in East Asian patients with acute coronary syndrome (ACS) using ticagrelor.

DESIGN

A multicenter prospective cohort study.

SETTING

Four sub center hospitals participating the study.

PATIENTS

Between March 2018 and July 2021, 208 patients with ACS were administered ticagrelor and underwent genetic testing.

INVERTENTION

Patients were enrolled and followed up for bleeding events for 12 months. Single-nucleotide polymorphisms (SNPs) were detected using whole-exome sequencing. SNPs significantly associated with cumulative bleeding events within 1-, 6-, and 12-month follow-ups were selected (p < 0.01). Among these, SNPs showing a difference of ≥2 fold in their distribution frequency among East Asians and Europeans were selected.

MEASUREMENTS AND MAIN RESULTS

Among all patients, 96.60% received ticagrelor plus aspirin or cilostazol, and 42.3% suffered from bleeding events during 12-month follow-up. Furthermore, 22 SNPs of 15 genes were found to have a significant association with cumulative bleeding events within 1-, 6-, and 12-month follow-ups. Among these SNPs, FIG4 rs2295837 (A>T) variant had the strongest association with bleeding events within 1 month (p = 1.28 × 10^-4 ), with an increased risk of bleeding in T allele carriers (odds ratio [OR]: 3.07, 95% confidence interval [CI]: 1.68-5.63). PROK2 rs3796224 (C>T) variant was most strongly associated with cumulative bleeding events within 6 months (p = 4.57 × 10^-4 ) with an increased risk of bleeding in T allele carriers (OR: 2.16, 95% CI: 1.20-3.89). Moreover, HRNR rs6662450 (C>T) variant showed the strongest relation with cumulative bleeding events within 12 months (p = 4.86 × 10^-4 ) with a reduced risk of bleeding in T allele carriers (OR: 0.48, 95% CI: 0.24-0.95).

CONCLUSION

Fifteen genes, including PROK2, HRNR, and FIG4, were potential biomarkers of high bleeding propensity in East Asian patients with ACS using ticagrelor.

Intracranial Hemorrhage During Dual Antiplatelet Therapy: JACC Review Topic of the Week

Dual antiplatelet therapy (DAPT) with acetylsalicylic acid and a P2Y₁₂ inhibitor is an established therapy for a broad spectrum of patients with cardiovascular disease. The ischemic benefit of DAPT is partially offset by its increased bleeding risk, with intracranial hemorrhage (ICH) being the most serious complication. Although uncommon (0.2%-0.3% annually), its cumulative burden can be substantial given the number of patients afflicted by cardiovascular disease worldwide. Patients with a history of stroke or transient ischemic attack harbor a particularly high risk for ICH when treated with DAPT. Prediction rules may assist clinicians when weighing the risk/benefit ratio of prescribing DAPT for patients with stroke/transient ischemic attack in the nonacute, ambulatory setting. Currently, there are no reversal agents that can rapidly and effectively reverse the effect of P2Y₁₂ inhibitors in routine practice, although a reversal agent for ticagrelor is under clinical investigation.

Development of imaging-based risk scores for prediction of intracranial haemorrhage and ischaemic stroke in patients taking antithrombotic therapy after ischaemic stroke or transient ischaemic attack: a pooled analysis of individual patient data from cohort studies

BACKGROUND

Balancing the risks of recurrent ischaemic stroke and intracranial haemorrhage is important for patients treated with antithrombotic therapy after ischaemic stroke or transient ischaemic attack. However, existing predictive models offer insufficient performance, particularly for assessing the risk of intracranial haemorrhage. We aimed to develop new risk scores incorporating clinical variables and cerebral microbleeds, an MRI biomarker of intracranial haemorrhage and ischaemic stroke risk.

METHODS

We did a pooled analysis of individual-patient data from the Microbleeds International Collaborative Network (MICON), which includes 38 hospital-based prospective cohort studies from 18 countries. All studies recruited participants with previous ischaemic stroke or transient ischaemic attack, acquired baseline MRI allowing quantification of cerebral microbleeds, and followed-up participants for ischaemic stroke and intracranial haemorrhage. Participants not taking antithrombotic drugs were excluded. We developed Cox regression models to predict the 5-year risks of intracranial haemorrhage and ischaemic stroke, selecting candidate predictors on biological relevance and simplifying models using backward elimination. We derived integer risk scores for clinical use. We assessed model performance in internal validation, adjusted for optimism using bootstrapping. The study is registered on PROSPERO, CRD42016036602.

FINDINGS

The included studies recruited participants between Aug 28, 2001, and Feb 4, 2018. 15 766 participants had follow-up for intracranial haemorrhage, and 15 784 for ischaemic stroke. Over a median follow-up of 2 years, 184 intracranial haemorrhages and 1048 ischaemic strokes were reported. The risk models we developed included cerebral microbleed burden and simple clinical variables. Optimism-adjusted c indices were 0·73 (95% CI 0·69-0·77) with a calibration slope of 0·94 (0·81-1·06) for the intracranial haemorrhage model and 0·63 (0·62-0·65) with a calibration slope of 0·97 (0·87-1·07) for the ischaemic stroke model. There was good agreement between predicted and observed risk for both models.

INTERPRETATION

The MICON risk scores, incorporating clinical variables and cerebral microbleeds, offer predictive value for the long-term risks of intracranial haemorrhage and ischaemic stroke in patients prescribed antithrombotic therapy for secondary stroke prevention; external validation is warranted.

FUNDING

British Heart Foundation and Stroke Association.

Frequency and Predictors of Major Bleeding in Patients With Embolic Strokes of Undetermined Source: NAVIGATE-ESUS Trial

BACKGROUND AND PURPOSE

Risks, sites, and predictors of major bleeding during antithrombotic therapies have not been well defined for patients with recent embolic stroke of undetermined source.

METHODS

Exploratory analysis of major bleeds defined by International Society of Thrombosis and Hemostasis criteria occurring among 7213 participants in international NAVIGATE (New Approach Rivaroxaban Inhibition of Factor Xa in a Global Trial) embolic stroke of undetermined source randomized trial comparing rivaroxaban 15 mg daily with aspirin 100 mg daily.

RESULTS

During a median follow-up of 11 months, 85 major bleeds occurred. The most frequent site was gastrointestinal (38%), followed by intracranial (29%). Assignment to rivaroxaban (hazard ratio [HR], 2.7 [95% CI, 1.7-4.3]), East Asia region (HR, 2.5 [95% CI, 1.6-3.9]), systolic blood pressure ≥160 mm Hg (HR, 2.2 [95% CI, 1.2-3.8]), and reduced estimated glomerular filtration rate (HR, 1.2 per 10 mL/min per 1.73 m² decrease, [95% CI, 1.0-1.3]) were independently associated with presence of major bleeds. Five (6%) were fatal. Among 15 patients with intracerebral hemorrhage, 2 (13%) were fatal. There was no evidence of an early high-risk period following initiation of rivaroxaban. The annualized rate of intracerebral hemorrhage was 6-fold higher among East Asian participants (0.67%) versus all other regions (0.11%; HR, 6.3 [95% CI, 2.2-18.0]). Distribution of bleeding sites was similar for rivaroxaban and aspirin.

CONCLUSIONS

Among embolic stroke of undetermined source patients participating in an international randomized trial, independent predictors of major bleeding were assignment to rivaroxaban, East Asia region, increased systolic blood pressure, and impaired renal function. East Asia as a region was strongly associated with risk of intracerebral hemorrhage. Estimated glomerular filtration rate should be a consideration for stratifying bleeding risk. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02313909.

Refining prediction of major bleeding on antiplatelet treatment after transient ischaemic attack or ischaemic stroke

Introduction

Bleeding is the main safety concern of treatment with antiplatelet drugs. We aimed to refine prediction of major bleeding on antiplatelet treatment after a transient ischaemic attack (TIA) or stroke by assessing the added value of new predictors to the existing S₂TOP-BLEED score.

Patients and methods

We used Cox regression analysis to study the association between candidate predictors and major bleeding among 2072 patients with a transient ischaemic attack or ischaemic stroke included in a population-based study (Oxford Vascular Study – OXVASC). An updated model was proposed and validated in 1094 patients with a myocardial infarction included in OXVASC. Models were compared with c-statistics, calibration plots, and net reclassification improvement.

Results

Independent predictors for major bleeding on top of S₂TOP-BLEED variables were peptic ulcer (hazard ratio (HR): 1.72; 1.04–2.86), cancer (HR: 2.40; 1.57–3.68), anaemia (HR: 1.55; 0.99–2.44) and renal failure (HR: 2.20; 1.57–4.28). Addition of those variables improved discrimination from 0.69 (0.64–0.73) to 0.73 (0.69–0.78) in the TIA/stroke cohort (p = 0.01). Performance improved particularly for upper gastro-intestinal bleeds (0.70; 0.64–0.75 to 0.77; 0.72–0.82). Net reclassification improved over the entire range of the score (net reclassification improvement: 0.56; 0.36–0.76). In the validation cohort, discriminatory performance improved from 0.68 (0.62–0.74) to 0.70 (0.64–0.76).

Discussion and Conclusion

Peptic ulcer, cancer, anaemia and renal failure improve predictive performance of the S₂TOP-BLEED score for major bleeding after stroke. Future external validation studies will be required to confirm the value of the STOP-BLEED+ score in transient ischaemic attack/stroke patients.

Stroke Outcomes With Vorapaxar Versus Placebo in Patients With Acute Coronary Syndromes: Insights From the TRACER Trial

Background

Vorapaxar, a protease‐activated receptor‐1 antagonist, is approved for secondary prevention of cardiovascular events but is associated with increased intracranial hemorrhage.

Methods and Results

TRACER (Thrombin Receptor Antagonist for Clinical Event Reduction in Acute Coronary Syndrome) was a trial of vorapaxar versus placebo among patients with acute coronary syndrome. Strokes were adjudicated by a central events committee. Of 12 944 patients, 199 (1.5%) had ≥1 stroke during the study period (median follow‐up, 477 days). Four patients had a single stroke of unknown type; 195 patients had ≥1 stroke classified as hemorrhagic or nonhemorrhagic (165 nonhemorrhagic, 28 hemorrhagic, and 2 both). Strokes occurred in 96 of 6473 patients (1.5%) assigned vorapaxar and 103 of 6471 patients (1.6%) assigned placebo. Kaplan‐Meier incidence of stroke for vorapaxar versus placebo was higher for hemorrhagic stroke (0.45% versus 0.14% [hazard ratio, 2.74; 95% confidence interval, 1.22–6.15]), lower but not significantly different for nonhemorrhagic stroke (1.53% versus 1.98% at 2 years [hazard ratio, 0.79; 95% confidence interval, 0.58–1.07]), and similar for stroke overall (1.93% versus 2.13% at 2 years [hazard ratio, 0.94; 95% confidence interval, 0.71–1.24]).

Conclusions

Stroke occurred in <2% of patients. Vorapaxar‐assigned patients had increased hemorrhagic stroke but a nonsignificant trend toward lower nonhemorrhagic stroke. Overall stroke frequency was similar with vorapaxar versus placebo.

Bleeding risk assessment for stroke patients on antithrombotic therapy

INTRODUCTION

After an ischemic cerebrovascular event the risk of new ischemic events is high, therefore antithrombotic therapy are indicated to prevent stroke recurrence.

DISCUSSION

Despite its clear benefit, these therapies increase the risk of bleeding. Therefore, it is essential to identify high hemorrhagic risk patients. There are different predictive models of hemorrhage, in particular of intracranial hemorrhage, associated with the use of antiaggregants in patients who have presented an ischemic stroke or TIA, such as the CCSC, intracranial scales -B2LEED3S score or S2TOP-BLEED. However, though main international guidelines recommend the use of scales, in particular, the HAS-BLED score, to assess the risk of bleeding in anticoagulated patients, there is no specific recommendation in the case of the use of antiplatelet drugs.

CONCLUSIONS

In this review we present the main models currently available for the prediction of bleeding of antithrombotic therapy in patients who have had a stroke or TIA.

External Validation of Risk Scores for Major Bleeding in a Population-Based Cohort of Transient Ischemic Attack and Ischemic Stroke Patients

BACKGROUND AND PURPOSE

The S₂TOP-BLEED score may help to identify patients at high risk of bleeding on antiplatelet drugs after a transient ischemic attack or ischemic stroke. The score was derived on trial populations, and its performance in a real-world setting is unknown. We aimed to externally validate the S₂TOP-BLEED score for major bleeding in a population-based cohort and to compare its performance with other risk scores for bleeding.

METHODS

We studied risk of bleeding in 2072 patients with a transient ischemic attack or ischemic stroke on antiplatelet agents in the population-based OXVASC (Oxford Vascular Study) according to 3 scores: S₂TOP-BLEED, REACH, and Intracranial-B₂LEED₃S. Performance was assessed with C statistics and calibration plots.

RESULTS

During 8302 patient-years of follow-up, 117 patients had a major bleed. The S₂TOP-BLEED score showed a C statistic of 0.69 (95% confidence interval [CI], 0.64-0.73) and accurate calibration for 3-year risk of major bleeding. The S₂TOP-BLEED score was much more predictive of fatal bleeding than nonmajor bleeding (C statistics 0.77; 95% CI, 0.69-0.85 and 0.50; 95% CI, 0.44-0.58). The REACH score had a C statistic of 0.63 (95% CI, 0.58-0.69) for major bleeding and the Intracranial-B₂LEED₃S score a C statistic of 0.60 (95% CI, 0.51-0.70) for intracranial bleeding. The ratio of ischemic events versus bleeds decreased across risk groups of bleeding from 6.6:1 in the low-risk group to 1.8:1 in the high-risk group.

CONCLUSIONS

The S₂TOP-BLEED score shows modest performance in a population-based cohort of patients with a transient ischemic attack or ischemic stroke. Although bleeding risks were associated with risks of ischemic events, risk stratification may still be useful to identify a subgroup of patients at particularly high risk of bleeding, in whom preventive measures are indicated.

Predicting major bleeding in patients with noncardioembolic stroke on antiplatelets: S2TOP-BLEED

OBJECTIVE

To develop and externally validate a prediction model for major bleeding in patients with a TIA or ischemic stroke on antiplatelet agents.

METHODS

We combined individual patient data from 6 randomized clinical trials (CAPRIE, ESPS-2, MATCH, CHARISMA, ESPRIT, and PRoFESS) investigating antiplatelet therapy after TIA or ischemic stroke. Cox regression analyses stratified by trial were performed to study the association between predictors and major bleeding. A risk prediction model was derived and validated in the PERFORM trial. Performance was assessed with the c statistic and calibration plots.

RESULTS

Major bleeding occurred in 1,530 of the 43,112 patients during 94,833 person-years of follow-up. The observed 3-year risk of major bleeding was 4.6% (95% confidence interval [CI] 4.4%-4.9%). Predictors were male sex, smoking, type of antiplatelet agents (aspirin-clopidogrel), outcome on modified Rankin Scale ≥3, prior stroke, high blood pressure, lower body mass index, elderly, Asian ethnicity, and diabetes (S₂TOP-BLEED). The S₂TOP-BLEED score had a c statistic of 0.63 (95% CI 0.60-0.64) and showed good calibration in the development data. Major bleeding risk ranged from 2% in patients aged 45-54 years without additional risk factors to more than 10% in patients aged 75-84 years with multiple risk factors. In external validation, the model had a c statistic of 0.61 (95% CI 0.59-0.63) and slightly underestimated major bleeding risk.

CONCLUSIONS

The S₂TOP-BLEED score can be used to estimate 3-year major bleeding risk in patients with a TIA or ischemic stroke who use antiplatelet agents, based on readily available characteristics. The discriminatory performance may be improved by identifying stronger predictors of major bleeding.