Long-Term Risk of Arterial Thrombosis After Intracerebral Hemorrhage: MUCH-Italy

Abstract

Background: The identification of patients surviving an acute intracerebral hemorrhage who are at a long-term risk of arterial thrombosis is a poorly defined, crucial issue for clinicians.

Methods: In the setting of the MUCH-Italy (Multicenter Study on Cerebral Haemorrhage in Italy) prospective observational cohort, we enrolled and followed up consecutive 30-day intracerebral hemorrhage survivors to assess the long-term incidence of arterial thrombotic events, to assess the impact of clinical and radiological variables on the risk of these events, and to develop a tool for estimating such a risk at the individual level. Primary end point was a composite of ischemic stroke, myocardial infarction, or other arterial thrombotic events. A point-scoring system was generated by the β-coefficients of the variables independently associated with the long-term risk of arterial thrombosis, and the predictive MUCH score was calculated as the sum of the weighted scores.

Results: Overall, 1729 patients (median follow-up time, 43 months [25th to 75th percentile, 69.0]) qualified for inclusion. Arterial thrombotic events occurred in 169 (9.7%) patients. Male sex, diabetes, hypercholesterolemia, atrial fibrillation, and personal history of coronary artery disease were associated with increased long-term risk of arterial thrombosis, whereas the use of statins and antithrombotic medications after the acute intracerebral hemorrhage was associated with a reduced risk. The area under the receiver operating characteristic curve of the MUCH score predictive validity was 0.716 (95% CI, 0.56-0.81) for the 0- to 1-year score, 0.672 (95% CI, 0.58-0.73) for the 0- to 5-year score, and 0.744 (95% CI, 0.65-0.81) for the 0- to 10-year score. C statistic for the prediction of events that occur from 0 to 10 years was 0.69 (95% CI, 0.64-0.74).

Conclusions: Intracerebral hemorrhage survivors are at high long-term risk of arterial thrombosis. The MUCH score may serve as a simple tool for risk estimation.

Keywords: area under curve; atrial fibrillation; cerebral hemorrhage; coronary artery disease; myocardial infarction.

Figure 1.

Participants’ enrollment and eligibility criteria flowchart. MUCH-Italy indicates Multicenter Study on Cerebral Haemorrhage in Italy.

Figure 2.

Predictive performance of the MUCH (Multicenter Study on Cerebral Haemorrhage) score. Receiver operating characteristic (ROC) curves to obtain the C statistic for arterial thrombotic events at 1 y (A), 5 y (B), and 10 y (C). AUC indicates area under the receiver operating characteristic curve; FP, false positive; and TP, true positive.

Figure 3.

One-y vs 5-y vs 10-y risk of arterial thrombotic events after intracerebral hemorrhage for subjects with different risk profiles. 1-year risk, 1−0.997 ^{exp(MUCH score)}; 5-year risk, 1−0.992 ^{exp(MUCH score)}; 10-year risk, 1−0.978 ^{exp(MUCH score)}.