The ABC-Bleeding Score is a Useful Tool for Patients on Anticoagulation Treatment

Investigators have used data from more than 20,000 atrial fibrillation (AFib) patients to develop and validate a biomarker-based risk score that predicted major bleeding in those patients better than 2 widely used alternatives.

Study team members used records from 14,537 patients in the phase 3 ARISTOTLE trial — which compared apixaban to warfarin — to devise and begin testing the ABC-bleeding score (Age, Biomarkers [growth differentiation factor-15, high-sensitivity cardiac troponin T, and hemoglobin], and Clinical history [previous bleeding]). They then used data from 8,468 patients in the phase 3 RE-LY trial — which compared dabigatran to warfarin — to perform external validation.

The ABC-bleeding score yielded a higher c-index for patients in both studies than scores on either HAS-BLED (Hypertension, Abnormal renal and liver function, Stroke, Bleeding, Labile INRs, Elderly, Drugs or alcohol) or ORBIT-AF (Outcomes Registry for Better Informed Treatment of Atrial Fibrillation).

Among ARISTOTLE trial patients, the c-index for the ABC-bleeding score was 0.68 (95% confidence interval [CI], 0.66 to 0.70) compared to 0.61 for HAS-BLED (95% CI, 0.59 to 0.63) and 0.65 for ORBIT (95% CI, 0.62 to 0.67). The p value for ABC-bleeding vs HAS-BLED was <0.0001 and p value for ABC-bleeding vs ORBIT was 0.0008.

Among RE-LY trial patients, the c-index for the ABC-bleeding score was 0.71 (95% CI, 0.68 to 0.73) compared to 0.62 for HAS-BLED (95% CI, 0.59 to 0.64) and 0.68 for ORBIT (95% CI, 0.65 to 0.70). The p value for ABC-bleeding vs HAS-BLED was <0.0001 and p value for ABC-bleeding vs ORBIT was 0.0016.

Neither the ARISTOTLE trial nor the RE-LY trial measured the blood markers used in the ABC-bleeding score, but both trials took blood plasma from a majority of their patients, and the study investigators analyzed that blood plasma to calculate each patient’s ABC-bleeding score.

“The ABC-bleeding score performed better than HAS-BLED and ORBIT scores and should be useful as decision support on anticoagulation treatment in patients with atrial fibrillation,” the study authors wrote in The Lancet, which published the findings just as they were being presented in Chicago at the scientific sessions of the American College of Cardiology meeting.

The ABC-bleeding score was developed at the Uppsala Clinical Research Center at Sweden’s Uppsala University. Researchers there have published several prior papers on blood biomarkers that can help predict bleeding and stroke risk.

“We think that biomarker-based risk evaluation in the near future will be the preferred tool for decision support at the selection of the optimal stroke prevention treatment for the individual patient with atrial fibrillation,” said Lars Wallentin, PhD, who has led the research and development project for many years.

Wallentin and his colleagues believe their risk evaluation tool has a number of advantages that make it more accurate than HAS-BLED and ORBIT, advantages such as the ability to reflect changes in patient health that change the concentrations of biomarkers in their blood.

The study team also says that its risk assessment tool is easy to use.

“The option to calculate the ABC-risk scores is already available today as an internet based tool and will shortly also be available as an app to facilitate its implementation in routine health care,” said Jonas Oldgren, who heads the Uppsala Clinical Research Center.