Medication History versus Point-of-Care Platelet Activity Testing in Patients with Intracerebral Hemorrhage

P2Y12 inhibitor use predicts hematoma expansion in patients with intracerebral hemorrhage

OBJECTIVE

Hematoma expansion (HE) predicts disability and death after acute intracerebral hemorrhage (ICH). Aspirin and anticoagulants have been associated with HE. We tested the hypothesis that P2Y12 inhibitors predict subsequent HE in patients. We explored laboratory measures of P2Y12 inhibition and dual antiplatelet therapy with aspirin (DAPT).

METHODS

We prospectively identified patients with ICH. Platelet activity was measured with the VerifyNow-P2Y12 assay. Hematoma volumes for initial and follow-up CTs were calculated using a validated semi-automated technique. HE was defined as the difference between hematoma volumes on the initial and follow-up CT scans. Nonparametric statistics were performed with Kruskal-Wallis H, and correction for multiple comparisons performed with Dunn's test.

RESULTS

In 194 patients, 15 (7.7%) were known to take a P2Y12 inhibitor (clopidogrel in all but one). Patients taking a P2Y12 inhibitor had more HE compared to patients not taking a P2Y12 inhibitor (3.5 [1.2-11.9] vs. 0.1 [-0.8-1.4] mL, p = 0.004). Patients taking DAPT experienced the most HE (7.2 [2.6-13.8] vs. 0.0 [-1.0-1.1] mL, p = 0.04). The use of P2Y12 inhibitors was associated with less P2Y12 activity (178 [149-203] vs. 288 [246-319] P2Y12 reaction units, p = 0.005).

INTERPRETATION

Patients taking a P2Y12 inhibitor had more HE and less P2Y12 activity. The effect was most pronounced in patients on DAPT, suggesting a synergistic effect of P2Y12 inhibitors and aspirin with respect to HE. Acute reversal of P2Y12 inhibitors in acute ICH requires further study.

Aspirin does not affect hematoma growth in severe spontaneous intracranial hematoma

Hematoma growth (HG) affects the prognosis of patients with spontaneous intracranial hematoma (ICH), but there is still a lack of evidence about the effects of aspirin (acetylsalicylic acid, ASA) on HG in patients with severe ICH. This study retrospectively analyzed patients with severe ICH who met the inclusion and exclusion criteria in Beijing Tiantan Hospital, Capital Medical University, between January 1, 2015, and July 31, 2019. Severe ICH patients were divided into ASA group and nASA groups according to ASA usage, and the incidence of HG between the groups was compared. Univariate analysis was performed by the Mann-Whitney U test, chi-square test, or Fisher exact test. Multivariate logistic regression analysis was used to analyze the impact of ASA on HG and to screen for risk factors of HG. In total, 221 patients with severe ICH were consecutively enrolled in this study. There were 72 (32.6%) patients in the ASA group and 149 patients in the nASA group. Although the incidence of HG in the nASA group was higher than that in the ASA group (34.9% VS 22.2%, p = 0.056), ASA did not significantly affect the occurrence of HG (p = 0.285) after adjusting for initial hematoma volume, high blood pressure at admission, coronary heart disease, and GCS at admission. In addition, we found that high blood pressure at admission was a risk factor for HG. Prior ASA does not increase the incidence of HG in severe ICH patients, and high blood pressure at admission is a risk factor for HG.

Antithrombotic and Antiplatelet Drug Toxicity

Anticoagulant and antiplatelet drugs target a specific portion of the coagulation cascade or the platelet activation and aggregation pathway. The primary toxicity associated with these agents is hemorrhage. Understanding the pharmacology of these drugs allows the treating clinician to choose the correct antidotal therapy. Reversal agents exist for some of these drugs; however, not all have proven patient-centered outcomes. The anticoagulants covered in this review are vitamin K antagonists, heparins, fondaparinux, hirudin derivatives, argatroban, oral factor Xa antagonists, and dabigatran. The antiplatelet agents reviewed are aspirin, adenosine diphosphate antagonists, dipyridamole, and glycoprotein IIb/IIIa antagonists. Additional notable toxicities are also reviewed.

The Effect of Preoperative Antiplatelet Therapy on Early Postoperative Rehemorrhage and Outcomes in Patients With Spontaneous Intracranial Hematoma

Background and Purpose

The effect of antiplatelet therapy (APT) on early postoperative rehemorrhage and outcomes of patients with spontaneous intracerebral hemorrhage (ICH) is still unclear. This study is to evaluate the effect of preoperative APT on early postoperative rehemorrhage and outcomes in ICH patients.

Methods

This was a multicenter cohort study. ICH patients undergoing surgery were divided into APT group and no antiplatelet therapy (nAPT) group according to whether patients received APT or not. Chi-square test, t-test, and Mann–Whitney U test were used to compare the differences in variables, postoperative rehematoma, and outcomes between groups. Multivariate logistics regression analysis was used to correct for confounding variables, which were different in group comparison.

Results

One hundred fifty ICH patients undergoing surgical treatment were consecutively included in this study. Thirty five (23.33%) people were included in the APT group, while 115 (76.67%) people were included in the nAPT group. The incidence of early postoperative rehemorrhage in the APT group was significantly higher than that in the nAPT group (25.7% VS 10.4%, p = 0.047 < 0.05). After adjustment for age, ischemic stroke history, and ventricular hematoma, preoperative APT had no significant effect on early postoperative rehemorrhage (p = 0.067). There was no statistical difference between the two groups in early poorer outcomes (p = 0.222) at 14 days after surgery. After adjustment for age, ischemic stroke history, and ventricular hematoma, preoperative APT also had no significant effect on early poorer modified Rankin Scale (mRS) (p = 0.072).

Conclusion

In conclusion, preoperative APT appears to be safe and have no significant effect on early postoperative rehematoma and outcomes in ICH patients.

Identifying Modifiable Predictors of Patient Outcomes After Intracerebral Hemorrhage with Machine Learning

BACKGROUND/OBJECTIVE

Demonstrating a benefit of acute treatment to patients with intracerebral hemorrhage (ICH) requires identifying which patients have a potentially modifiable outcome, where treatment could favorably shift a patient's expected outcome. A decision rule for which patients have a modifiable outcome could improve the targeting of treatments. We sought to determine which patients with ICH have a modifiable outcome.

METHODS

Patients with ICH were prospectively identified at two institutions. Data on hematoma volumes, medication histories, and other variables of interest were collected. ICH outcomes were evaluated using the modified Rankin Scale (mRS), assessed at 14 days and 3 months after ICH, with "good outcome" defined as 0-3 (independence or better) and "poor outcome" defined as 4-6 (dependence or worse). Supervised machine learning models identified the best predictors of good versus poor outcomes at Institution 1. Models were validated using repeated fivefold cross-validation as well as testing on the entirely independent sample at Institution 2. Model fit was assessed with area under the ROC curve (AUC).

RESULTS

Model performance at Institution 1 was strong for both 14-day (AUC of 0.79 [0.77, 0.81] for decision tree, 0.85 [0.84, 0.87] for random forest) and 3 month (AUC of 0.75 [0.73, 0.77] for decision tree, 0.82 [0.80, 0.84] for random forest) outcomes. Independent predictors of functional outcome selected by the algorithms as important included hematoma volume at hospital admission, hematoma expansion, intraventricular hemorrhage, overall ICH Score, and Glasgow Coma Scale. Hematoma expansion was the only potentially modifiable independent predictor of outcome and was compatible with "good" or "poor" outcome in a subset of patients with low hematoma volumes, good Glasgow Coma scale and premorbid modified Rankin Scale scores. Models trained on harmonized data also predicted patient outcomes well at Institution 2 using decision tree (AUC 0.69 [0.63, 0.75]) and random forests (AUC 0.78 [0.72, 0.84]).

CONCLUSIONS

Patient outcomes are predictable to a high level in patients with ICH, and hematoma expansion is the sole-modifiable predictor of these outcomes across two outcome types and modeling approaches. According to decision tree analyses predicting outcome at 3 months, patients with a high Glasgow Coma Scale score, less than 44.5 mL hematoma volume at admission, and relatively low premorbid modified Rankin Score in particular have a modifiable outcome and appear to be candidates for future interventions to improve outcomes after ICH.

Cohort analysis of desmopressin effect on hematoma expansion in patients with spontaneous intracerebral hemorrhage and documented pre-ictus antiplatelet use

Antiplatelet therapy at the time of spontaneous intracerebral hemorrhage (sICH) may increase risk for hemorrhage expansion and mortality. Current guidelines recommend considering a single dose of desmopressin in sICH associated with cyclooxygenase-1 inhibitors or adenosine diphosphate receptor inhibitors. Adult subjects with sICH and concomitant antiplatelet therapy admitted to a large, tertiary care center were included. We sought to compare the risk of hematoma expansion in patients that received desmopressin for antiplatelet reversal in the setting of sICH to similar patients that did not receive desmopressin. The primary outcomes were the incidence of relative and absolute hematoma expansion. In total, 71 patients (29 received desmopressin, 42 did not receive desmopressin) were analyzed. All patients in the desmopressin group received a 0.3 mcg/kg intravenous dose prior to hematoma expansion assessment. Relative hematoma expansion occurred in 5/29 (17%) with desmopressin compared to 11/42 (26%) without desmopressin (OR 0.59 [95% CI 0.18-1.92]). Absolute hematoma expansion occurred in 9/29 (30%) with desmopressin compared to 12/42 (28%) without desmopressin (OR 1.13 [95% CI 0.40-3.16]). Multiple logistic regression controlling for significant covariates did not reveal a significant effect of desmopressin on relative or absolute hematoma expansion (OR 0.65 [95% CI 0.18-2.43] and OR 1.55 [0.48-4.99], respectively). We failed to find evidence that desmopressin administration for antiplatelet reversal in sICH reduces the incidence of hematoma expansion. Larger studies, focusing on the early phase of sICH, are needed to characterize the clinical efficacy and safety of desmopressin for antiplatelet reversal before widespread implementation.