β-Trace Protein and Prognosis in Patients With Atrial Fibrillation Receiving Anticoagulation Treatment

Background: Atrial fibrillation (AF) is associated with a high risk of mortality and morbidity and it commonly coexists with chronic kidney disease. A biomarker of renal function, beta-trace protein (BTP), has been implicated in the progression of cardiovascular disease. The aim of our study was to evaluate the association of BTP with adverse cardiovascular events, bleeding, and mortality in patients with AF. Methods: In a consecutive cohort of patients with nonvalvular AF receiving anticoagulation treatment, plasma BTP was determined using an automated nephelometer BN ProSpec System (Siemens) and related to estimated glomerular filtration rate (eGFR). We recorded adverse cardiovascular events (stroke, acute coronary syndrome, and acute pulmonary edema), major bleeding, and mortality. Results: We included 1,279 patients (48.6% men), aged 76 years (IQR, 71-81 years), who were followed up for 996 days (IQR, 802-1,254 days). During the follow-up, there were 150 cardiovascular events (annual rate, 3.99%), 57 embolisms (annual rate, 1.54%), and 114 major bleeding events (annual rate, 3.04%), and 161 patients died (annual rate, 4.32%). BTP levels were inversely associated with eGFR (P < .001). High BTP concentrations were significantly associated with embolic events (hazard ratio [HR], 4.64 [1.98-10.86]; P < .001), composite adverse cardiovascular events (HR, 1.93 [1.31-2.85]; P = .001), and mortality (HR, 2.08 [1.49-2.90]; P < .001), even after adjusting for CHAD(2)DS(2)-VASc (congestive heart failure, hypertension, age >= 75 years [doubled], diabetes mellitus, stroke [doubled], vascular disease, age 65 to 74 years, sex category) score and renal function. High BTP was associated with major bleeding events (HR, 1.88 [1.18-3.00]; P = .008), even after adjusting for the HAS-BLED (hypertension, abnormal renal/liver function, stroke, bleeding history or redisposition, labile international normalized ratio, elderly [>65 years], drugs/alcohol concomitantly) score. Conclusions: We suggest that BTP, a proposed renal damage biomarker, may be a novel predictor of adverse cardiovascular events, major bleeding, and mortality in patients with AF. BTP may help refine clinical risk stratification in these patients.