Bleeding and embolic risk in patients with atrial fibrillation and cancer.

INTRODUCTION AND OBJECTIVES: The impact of cancer on clinical outcomes in patients with atrial fibrillation (AF) is unclear. The aim of this study was to assess how cancer influences the prediction and risk of embolic and hemorrhagic events in patients with AF. METHODS: The study population comprised 16 056 patients from a Spanish health area diagnosed with AF between 2014 and 2018. Of these, 1137 (7.1%) had a history of cancer. During a median follow-up of 4.9 years, we assessed the relationship between cancer and bleeding and embolic events by competing risk analysis, considering death as a competing risk. RESULTS: No association was detected between an increased risk of embolic events and cancer overall (sHR, 0.73; 95%CI, 0.41-1.26), active cancer, or any subgroup of cancer. However, cancer was associated with an increased risk of bleeding, although only in patients with active cancer (sHR, 1.42; 95%CI, 1.20-1.67) or prior radiotherapy (sHR, 1.40; 95%CI, 1.19-1.65). Both the CHA2DS2-VASc and HAS-BLED scores showed suboptimal performance to predict embolic and bleeding risk (c-statistic <0.50), respectively, in nonanticoagulated patients with active cancer. The ratio between the increase in bleeding and the decrease in embolisms with anticoagulation was similar in patients with and without cancer (5.6 vs 7.8; P <.001). CONCLUSIONS: Cancer was not associated with an increased risk of embolic events in AF patients, only with an increased risk of bleeding. However, active cancer worsened the ability of the CHA2DS2-VASc and HAS-BLED scores to predict embolic and bleeding events, respectively, in nonanticoagulated patients.

Validation of Embolic and Bleeding Risk Scores in Patients With Atrial Fibrillation and Cancer.

Little is known about the prediction of atrial fibrillation (AF) risk scores in patients with cancer. The aim of this study was to assess the predictive ability of the CHA2DS2-VASc and HAS-BLED scores in patients with AF and cancer. Overall, 16,056 patients with AF diagnosed between 2014 and 2018 from a Spanish health area, including 1,137 patients with cancer, were observed during a median follow-up of 4.9 years. Although discrimination was similar between patients with cancer and patients without cancer who were treated with anticoagulation therapy (0.56 and 0.58), in patients with cancer who were not treated with anticoagulation therapy, c-statistic of CHA2DS2-VASc was poor and significantly lower than in the patients without cancer (0.42 vs 0.65). The overall precision of the CHA2DS2-VASc score was good throughout the follow-up (Brier score < 0.1), in patients with and without cancer. Regarding the HAS-BLED score, calibration and discrimination were poor in patients with cancer (c-statistic 0.51), similar to those in patients without cancer (c-statistic 0.53). In patients with cancer who were not treated with anticoagulation therapy, the embolic risk CHA2DS2-VASc score = 1 was similar to CHA2DS2-VASc score ≥ 2. Only patients with AF and cancer and CHA2DS2-VASc score = 0 presented a low risk of embolic events (negative predictive value 100%). A HAS-BLED score > 3 was not associated with higher bleeding risk in patients with cancer (p > 0.05). In summary, in patients with cancer and with AF, neither the CHA2DS2-VASc score nor the HAS-BLED score was useful for predicting embolic and hemorrhagic events, respectively. However, a CHA2DS2-VASc score 0 is useful to identify patients with AF and cancer who are at low embolic risk.