Ziad Hijazi

Efficacy of apixaban when compared with warfarin in relation to renal function in patients with atrial fibrillation: insights from the ARISTOTLE trial

AIMS Atrial fibrillation (AF) is common among patients with impaired renal function. Apixaban, a novel oral anticoagulant with partial renal excretion, was compared with warfarin and reduced the rate stroke, death and bleeding in the ARISTOTLE trial. We evaluated these outcomes in relation to renal function. METHODS AND RESULTS Baseline glomerular filtration rate (GFR) was estimated using the Cockcroft-Gault and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations as well as cystatin C measurements. According to baseline Cockcroft-Gault, there were 7518 patients (42%) with an estimated GFR (eGFR) of >80 mL/min, 7587 (42%) between >50 and 80 mL/min, and 3017 (15%) with an eGFR of ≤50 mL/min. The rate of cardiovascular events and bleeding was higher at impaired renal function (≤80 mL/min). Apixaban was more effective than warfarin in preventing stroke or systemic embolism and reducing mortality irrespective of renal function. These results were consistent, regardless of methods for GFR estimation. Apixaban was associated with less major bleeding events across all ranges of eGFRs. The relative risk reduction in major bleeding was greater in patients with an eGFR of ≤50 mL/min using Cockcroft-Gault {hazard ratio (HR) 0.50 [95% confidence interval (CI) 0.38-0.66], interaction P = 0.005} or CKD-EPI equations [HR 0.48 (95% CI 0.37-0.64), interaction P = 0.003]. CONCLUSION In patients with AF, renal impairment was associated with increased risk of cardiovascular events and bleeding. When compared with warfarin, apixaban treatment reduced the rate of stroke, death, and major bleeding, regardless of renal function. Patients with impaired renal function seemed to have the greatest reduction in major bleeding with apixaban.

Cardiac Biomarkers Are Associated With an Increased Risk of Stroke and Death in Patients With Atrial Fibrillation A Randomized Evaluation of Long-Term Anticoagulation Therapy (RE-LY) Substudy

Background— Cardiac biomarkers are strong predictors of adverse outcomes in several patient populations. We evaluated the prevalence of elevated troponin I and N-terminal pro-B-type natriuretic peptide (NT-proBNP) and their association to cardiovascular events in atrial fibrillation (AF) patients in the Randomized Evaluation of Long-Term Anticoagulation Therapy (RE-LY) trial. Methods and Results— Biomarkers at randomization were analyzed in 6189 patients. Outcomes were evaluated by Cox proportional hazards models adjusting for established cardiovascular risk factors and the CHADS2 and CHA2DS2-VASc risk scores. Patients were stratified based on troponin I concentrations: <0.010 &mgr;g/L, n=2663; 0.010 to 0.019 &mgr;g/L, n=2006; 0.020 to 0.039 &mgr;g/L, n=1023; ≥0.040 &mgr;g/L, n=497; and on NT-proBNP concentration quartiles: <387; 387 to 800; 801 to 1402; >1402 ng/L. Rates of stroke were independently related to levels of troponin I with 2.09%/year in the highest and 0.84%/year in the lowest troponin I group (hazard ratio [HR], 1.99 [95% CI, 1.17–3.39]; P=0.0040), and to NT-proBNP with 2.30%/year versus 0.92% in the highest versus lowest NT-proBNP quartile groups, (HR, 2.40 [95% CI, 1.41–4.07]; P=0.0014). Vascular mortality was also independently related to biomarker levels with 6.56%/year in the highest and 1.04%/year the lowest troponin I group (HR, 4.38 [95% CI, 3.05–6.29]; P<0.0001), and 5.00%/year in the highest and 0.61%/year in the lowest NT-proBNP quartile groups (HR, 6.73 [3.95–11.49]; P<0.0001). Biomarkers increased the C-statistic from 0.68 to 0.72, P<0.0001, for a composite of thromboembolic events. Conclusions— Elevations of troponin I and NT-proBNP are common in patients with AF and independently related to increased risks of stroke and mortality. Cardiac biomarkers seem useful for improving risk prediction in AF beyond currently used clinical variables. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00262600.Background —Cardiac biomarkers are strong predictors of adverse outcomes in several patient populations. We evaluated the prevalence of elevated troponin I and NT-proBNP and their association to cardiovascular events in atrial fibrillation (AF) patients in the RELY trial. Methods and Results —Biomarkers at randomization were analyzed in 6189 patients. Outcomes were evaluated by Cox proportional hazards models adjusting for established cardiovascular risk factors and the CHADS2 and CHA2DS2-VASc risk scores. Patients were stratified based on troponin I concentrations: 1402 ng/L. Rates of stroke were independently related to levels of troponin I with 2.09%/year in the highest and 0.84%/year in the lowest troponin I group (hazard ratio (HR) 1.99 [95% confidence interval (CI) 1.17-3.39], p=0.0040), and to NT-proBNP with 2.30%/year vs. 0.92% in the highest vs. lowest NT-proBNP quartile groups, (HR 2.40 [CI 1.41-4.07], p=0.0014). Vascular mortality was also independently related to biomarker levels with 6.56%/year in the highest and 1.04%/year the lowest troponin I group (HR 4.38 [CI 3.05-6.29] p<0.0001), and 5.00%/year in the highest and 0.61%/year in the lowest NT-proBNP quartile groups (HR 6.73 [3.95-11.49] p<0.0001). Biomarkers increased the C-statistic from 0.68 to 0.72, p<0.0001, for a composite of thromboembolic events. Conclusions —Elevations of troponin I and NT-proBNP are common in patients with AF and independently related to increased risks of stroke and mortality. Cardiac biomarkers seem useful for improving risk prediction in AF beyond currently used clinical variables. Clinical Trial Registration Information —www.clinicaltrials.gov; [NCT00262600][1] [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT00262600&atom=%2Fcirculationaha%2Fearly%2F2012%2F02%2F28%2FCIRCULATIONAHA.111.038729.atom

Cardiac Biomarkers are Associated with an Increased Risk of Stroke and Death in Patients with Atrial Fibrillation: A RELY Substudy

Background— Cardiac biomarkers are strong predictors of adverse outcomes in several patient populations. We evaluated the prevalence of elevated troponin I and N-terminal pro-B-type natriuretic peptide (NT-proBNP) and their association to cardiovascular events in atrial fibrillation (AF) patients in the Randomized Evaluation of Long-Term Anticoagulation Therapy (RE-LY) trial. Methods and Results— Biomarkers at randomization were analyzed in 6189 patients. Outcomes were evaluated by Cox proportional hazards models adjusting for established cardiovascular risk factors and the CHADS2 and CHA2DS2-VASc risk scores. Patients were stratified based on troponin I concentrations: <0.010 &mgr;g/L, n=2663; 0.010 to 0.019 &mgr;g/L, n=2006; 0.020 to 0.039 &mgr;g/L, n=1023; ≥0.040 &mgr;g/L, n=497; and on NT-proBNP concentration quartiles: <387; 387 to 800; 801 to 1402; >1402 ng/L. Rates of stroke were independently related to levels of troponin I with 2.09%/year in the highest and 0.84%/year in the lowest troponin I group (hazard ratio [HR], 1.99 [95% CI, 1.17–3.39]; P=0.0040), and to NT-proBNP with 2.30%/year versus 0.92% in the highest versus lowest NT-proBNP quartile groups, (HR, 2.40 [95% CI, 1.41–4.07]; P=0.0014). Vascular mortality was also independently related to biomarker levels with 6.56%/year in the highest and 1.04%/year the lowest troponin I group (HR, 4.38 [95% CI, 3.05–6.29]; P<0.0001), and 5.00%/year in the highest and 0.61%/year in the lowest NT-proBNP quartile groups (HR, 6.73 [3.95–11.49]; P<0.0001). Biomarkers increased the C-statistic from 0.68 to 0.72, P<0.0001, for a composite of thromboembolic events. Conclusions— Elevations of troponin I and NT-proBNP are common in patients with AF and independently related to increased risks of stroke and mortality. Cardiac biomarkers seem useful for improving risk prediction in AF beyond currently used clinical variables. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00262600.Background —Cardiac biomarkers are strong predictors of adverse outcomes in several patient populations. We evaluated the prevalence of elevated troponin I and NT-proBNP and their association to cardiovascular events in atrial fibrillation (AF) patients in the RELY trial. Methods and Results —Biomarkers at randomization were analyzed in 6189 patients. Outcomes were evaluated by Cox proportional hazards models adjusting for established cardiovascular risk factors and the CHADS2 and CHA2DS2-VASc risk scores. Patients were stratified based on troponin I concentrations: 1402 ng/L. Rates of stroke were independently related to levels of troponin I with 2.09%/year in the highest and 0.84%/year in the lowest troponin I group (hazard ratio (HR) 1.99 [95% confidence interval (CI) 1.17-3.39], p=0.0040), and to NT-proBNP with 2.30%/year vs. 0.92% in the highest vs. lowest NT-proBNP quartile groups, (HR 2.40 [CI 1.41-4.07], p=0.0014). Vascular mortality was also independently related to biomarker levels with 6.56%/year in the highest and 1.04%/year the lowest troponin I group (HR 4.38 [CI 3.05-6.29] p<0.0001), and 5.00%/year in the highest and 0.61%/year in the lowest NT-proBNP quartile groups (HR 6.73 [3.95-11.49] p<0.0001). Biomarkers increased the C-statistic from 0.68 to 0.72, p<0.0001, for a composite of thromboembolic events. Conclusions —Elevations of troponin I and NT-proBNP are common in patients with AF and independently related to increased risks of stroke and mortality. Cardiac biomarkers seem useful for improving risk prediction in AF beyond currently used clinical variables. Clinical Trial Registration Information —www.clinicaltrials.gov; [NCT00262600][1] [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT00262600&atom=%2Fcirculationaha%2Fearly%2F2012%2F02%2F28%2FCIRCULATIONAHA.111.038729.atom

Efficacy and Safety of Dabigatran Compared With Warfarin in Relation to Baseline Renal Function in Patients With Atrial Fibrillation A RE-LY (Randomized Evaluation of Long-term Anticoagulation Therapy) Trial Analysis

Background— Renal impairment increases the risk of stroke and bleeding in patients with atrial fibrillation. In the Randomized Evaluation of Long-Term Anticoagulant Therapy (RELY) trial, dabigatran, with ≈80% renal elimination, displayed superiority over warfarin for prevention of stroke and systemic embolism in the 150-mg dose and significantly less major bleeding in the 110-mg dose in 18 113 patients with nonvalvular atrial fibrillation. This prespecified study investigated these outcomes in relation to renal function. Methods and Results— Glomerular filtration rate was estimated with the Cockcroft-Gault, Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), and Modification of Diet in Renal Disease (MDRD) equations in all randomized patients with available creatinine at baseline (n=17 951), and cystatin C–based glomerular filtration rate was estimated in a subpopulation with measurements available (n=6190). A glomerular filtration rate ≥80, 50 to 0.1 for all). For the outcome of major bleeding, there were significant interactions between treatment and renal function according to CKD-EPI and MDRD equations, respectively ( P <0.05). The relative reduction in major bleeding with either dabigatran dose compared with warfarin was greater in patients with glomerular filtration rate ≥80 mL/min. Conclusions— The efficacy of both dosages of dabigatran was consistent with the overall trial irrespective of renal function. However, with the CKD-EPI and MDRD equations, both dabigatran dosages displayed significantly lower rates of major bleeding in patients with glomerular filtration rate ≥80 mL/min. Clinical Trial Registration— URL: . Unique identifier: [NCT00262600][1]. # Clinical Perspective {#article-title-26} [1]: /lookup/external-ref?link_type=CLINTRIALGOV&access_num=NCT00262600&atom=%2Fcirculationaha%2F129%2F9%2F961.atomBackground— Renal impairment increases the risk of stroke and bleeding in patients with atrial fibrillation. In the Randomized Evaluation of Long-Term Anticoagulant Therapy (RELY) trial, dabigatran, with ≈80% renal elimination, displayed superiority over warfarin for prevention of stroke and systemic embolism in the 150-mg dose and significantly less major bleeding in the 110-mg dose in 18 113 patients with nonvalvular atrial fibrillation. This prespecified study investigated these outcomes in relation to renal function. Methods and Results— Glomerular filtration rate was estimated with the Cockcroft-Gault, Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), and Modification of Diet in Renal Disease (MDRD) equations in all randomized patients with available creatinine at baseline (n=17 951), and cystatin C–based glomerular filtration rate was estimated in a subpopulation with measurements available (n=6190). A glomerular filtration rate ≥80, 50 to <80, and <50 mL/min was estimated in 32.6%, 47.6%, and 19.8% and in 21.6%, 59.6%, and 18.8% of patients based on Cockcroft-Gault and CKD-EPI, respectively. Rates of stroke or systemic embolism, major bleeding, and all-cause mortality increased as renal function decreased. The rates of stroke or systemic embolism were lower with dabigatran 150 mg and similar with 110 mg twice daily compared with warfarin, without significant heterogeneity in subgroups defined by renal function (interaction P>0.1 for all). For the outcome of major bleeding, there were significant interactions between treatment and renal function according to CKD-EPI and MDRD equations, respectively (P<0.05). The relative reduction in major bleeding with either dabigatran dose compared with warfarin was greater in patients with glomerular filtration rate ≥80 mL/min. Conclusions— The efficacy of both dosages of dabigatran was consistent with the overall trial irrespective of renal function. However, with the CKD-EPI and MDRD equations, both dabigatran dosages displayed significantly lower rates of major bleeding in patients with glomerular filtration rate ≥80 mL/min. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00262600.

Biomarkers in atrial fibrillation: a clinical review

Assessment of atrial fibrillation (AF)-associated stroke risk is at present mainly based on clinical risk scores such as CHADS2 and CHA2DS2-VASc, although these scores provide only modest discrimination of risk for individual patients. Biomarkers derived from the blood may help refine risk assessment in AF for stroke outcomes and for mortality. Recent studies of biomarkers in AF have shown that they can substantially improve risk stratification. Cardiac biomarkers, such as troponin and natriuretic peptides, significantly improve risk stratification in addition to current clinical risk stratification models. Similar findings have recently been described for markers of renal function, coagulation, and inflammation in AF populations based on large randomized prospective clinical trials or large community-based cohorts. These new findings may enable development of novel tools to improve clinical risk assessment in AF. Biomarkers in AF may also improve the understanding of the pathophysiology of AF further as well as potentially elucidate novel treatment targets. This review will highlight novel associations of biomarkers and outcomes in AF as well as recent progress in the use of biomarkers for risk stratification.

The novel biomarker-based ABC (age, biomarkers, clinical history)-bleeding risk score for patients with atrial fibrillation: a derivation and validation study

BACKGROUND The benefit of oral anticoagulation in atrial fibrillation is based on a balance between reduction in ischaemic stroke and increase in major bleeding. We aimed to develop and validate a new biomarker-based risk score to improve the prognostication of major bleeding in patients with atrial fibrillation. METHODS We developed and internally validated a new biomarker-based risk score for major bleeding in 14,537 patients with atrial fibrillation randomised to apixaban versus warfarin in the ARISTOTLE trial and externally validated it in 8468 patients with atrial fibrillation randomised to dabigatran versus warfarin in the RE-LY trial. Plasma samples for determination of candidate biomarker concentrations were obtained at randomisation. Major bleeding events were centrally adjudicated. The predictive values of biomarkers and clinical variables were assessed with Cox regression models. The most important variables were included in the score with weights proportional to the model coefficients. The ARISTOTLE and RE-LY trials are registered with ClinicalTrials.gov, numbers NCT00412984 and NCT00262600, respectively. FINDINGS The most important predictors for major bleeding were the concentrations of the biomarkers growth differentiation factor-15 (GDF-15), high-sensitivity cardiac troponin T (cTnT-hs) and haemoglobin, age, and previous bleeding. The ABC-bleeding score (age, biomarkers [GDF-15, cTnT-hs, and haemoglobin], and clinical history [previous bleeding]) score yielded a higher c-index than the conventional HAS-BLED and the newer ORBIT scores for major bleeding in both the derivation cohort (0·68 [95% CI 0·66-0·70] vs 0·61 [0·59-0·63] vs 0·65 [0·62-0·67], respectively; ABC-bleeding vs HAS-BLED p<0·0001 and ABC-bleeding vs ORBIT p=0·0008). ABC-bleeding score also yielded a higher c-index score in the the external validation cohort (0·71 [95% CI 0·68-0·73] vs 0·62 [0·59-0·64] for HAS-BLED vs 0·68 [0·65-0·70] for ORBIT; ABC-bleeding vs HAS-BLED p<0·0001 and ABC-bleeding vs ORBIT p=0·0016). A modified ABC-bleeding score using alternative biomarkers (haematocrit, cTnI-hs, cystatin C, or creatinine clearance) also outperformed the HAS-BLED and ORBIT scores. INTERPRETATION The ABC-bleeding score, using age, history of bleeding, and three biomarkers (haemoglobin, cTn-hs, and GDF-15 or cystatin C/CKD-EPI) was internally and externally validated and calibrated in large cohorts of patients with atrial fibrillation receiving anticoagulation therapy. 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. FUNDING BMS, Pfizer, Boehringer Ingelheim, Roche Diagnostics.

The ABC (age, biomarkers, clinical history) stroke risk score: a biomarker-based risk score for predicting stroke in atrial fibrillation

Abstract Aims Atrial fibrillation (AF) is associated with an increased risk of stroke, which is currently estimated by clinical characteristics. The cardiac biomarkers N-terminal fragment B-type natriuretic peptide (NT-proBNP) and cardiac troponin high-sensitivity (cTn-hs) are independently associated with risk of stroke in AF. Our objective was to develop and validate a new biomarker-based risk score to improve prognostication of stroke in patients with AF. Methods and results A new risk score was developed and internally validated in 14 701 patients with AF and biomarkers levels determined at baseline, median follow-up of 1.9 years. Biomarkers and clinical variables significantly contributing to predicting stroke or systemic embolism were assessed by Cox-regression and each variable obtained a weight proportional to the model coefficients. External validation was performed in 1400 patients with AF, median follow-up of 3.4 years. The most important predictors were prior stroke/transient ischaemic attack, NT-proBNP, cTn-hs, and age, which were included in the ABC ( A ge, B iomarkers, C linical history) stroke risk score. The ABC-stroke score was well calibrated and yielded higher c-indices than the widely used CHA 2 DS 2 -VASc score in both the derivation cohort (0.68 vs. 0.62, P < 0.001) and the external validation cohort (0.66 vs. 0.58, P < 0.001). Moreover, the ABC-stroke score consistently provided higher c-indices in several important subgroups. Conclusion A novel biomarker-based risk score for predicting stroke in AF was successfully developed and internally validated in a large cohort of patients with AF and further externally validated in an independent AF cohort. The ABC-stroke score performed better than the presently used clinically based risk score and may provide improved decision support in AF. ClinicalTrials. gov identifier NCT00412984, NCT00799903.

Growth Differentiation Factor 15, a Marker of Oxidative Stress and Inflammation, for Risk Assessment in Patients With Atrial Fibrillation Insights From the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) Trial

Background—Growth differentiation factor 15 (GDF-15), high-sensitivity troponin, and N-terminal pro-brain natriuretic peptide levels are predictive of death and cardiovascular events in healthy elderly subjects, patients with acute coronary syndrome, and patients with heart failure. High-sensitivity troponin I and N-terminal pro-brain natriuretic peptide are also prognostic in patients with atrial fibrillation. We evaluated the prognostic value of GDF-15 alone and in addition to clinical characteristics and other biomarkers in patients with atrial fibrillation. Methods and Results—The Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) trial randomized 18 201 patients with atrial fibrillation to apixaban or warfarin. Biomarkers were measured at randomization in 14 798 patients. Efficacy and safety outcomes during 1.9 years of follow-up were compared across quartiles of GDF-15 by use of Cox analyses adjusted for clinical characteristics, randomized treatment,...Background— Growth differentiation factor 15 (GDF-15), high-sensitivity troponin, and N-terminal pro-brain natriuretic peptide levels are predictive of death and cardiovascular events in healthy elderly subjects, patients with acute coronary syndrome, and patients with heart failure. High-sensitivity troponin I and N-terminal pro-brain natriuretic peptide are also prognostic in patients with atrial fibrillation. We evaluated the prognostic value of GDF-15 alone and in addition to clinical characteristics and other biomarkers in patients with atrial fibrillation. Methods and Results— The Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) trial randomized 18 201 patients with atrial fibrillation to apixaban or warfarin. Biomarkers were measured at randomization in 14 798 patients. Efficacy and safety outcomes during 1.9 years of follow-up were compared across quartiles of GDF-15 by use of Cox analyses adjusted for clinical characteristics, randomized treatment, and other biomarkers. The GDF-15 level showed a median of 1383 ng/L (interquartile range, 977–2052 ng/L). Annual rates of stroke or systemic embolism ranged from 0.9% to 2.03% (P<0.001); of major bleeding, from 1.22% to 4.53% (P<0.001); and of mortality, from 1.34% to 7.19% (P<0.001) in the lowest compared with the highest GDF-15 quartile. The prognostic information provided by GDF-15 was independent of clinical characteristics and clinical risk scores. Adjustment for the other cardiac biomarkers attenuated the prognostic value for stroke, whereas the prognostic value for mortality and major bleeding remained. Apixaban consistently reduced stroke, mortality, and bleeding, regardless of GDF-15 levels. Conclusions— GDF-15 is a risk factor for major bleeding, mortality, and stroke in atrial fibrillation. The prognostic value for major bleeding and death remained even in the presence of N-terminal pro-brain natriuretic peptide and high-sensitivity troponin I. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00412984.

Growth Differentiation Factor 15, a Marker of Oxidative Stress and Inflammation, for Risk Assessment in Patients with Atrial Fibrillation: Insights from the ARISTOTLE Trial

Background—Growth differentiation factor 15 (GDF-15), high-sensitivity troponin, and N-terminal pro-brain natriuretic peptide levels are predictive of death and cardiovascular events in healthy elderly subjects, patients with acute coronary syndrome, and patients with heart failure. High-sensitivity troponin I and N-terminal pro-brain natriuretic peptide are also prognostic in patients with atrial fibrillation. We evaluated the prognostic value of GDF-15 alone and in addition to clinical characteristics and other biomarkers in patients with atrial fibrillation. Methods and Results—The Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) trial randomized 18 201 patients with atrial fibrillation to apixaban or warfarin. Biomarkers were measured at randomization in 14 798 patients. Efficacy and safety outcomes during 1.9 years of follow-up were compared across quartiles of GDF-15 by use of Cox analyses adjusted for clinical characteristics, randomized treatment,...Background— Growth differentiation factor 15 (GDF-15), high-sensitivity troponin, and N-terminal pro-brain natriuretic peptide levels are predictive of death and cardiovascular events in healthy elderly subjects, patients with acute coronary syndrome, and patients with heart failure. High-sensitivity troponin I and N-terminal pro-brain natriuretic peptide are also prognostic in patients with atrial fibrillation. We evaluated the prognostic value of GDF-15 alone and in addition to clinical characteristics and other biomarkers in patients with atrial fibrillation. Methods and Results— The Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) trial randomized 18 201 patients with atrial fibrillation to apixaban or warfarin. Biomarkers were measured at randomization in 14 798 patients. Efficacy and safety outcomes during 1.9 years of follow-up were compared across quartiles of GDF-15 by use of Cox analyses adjusted for clinical characteristics, randomized treatment, and other biomarkers. The GDF-15 level showed a median of 1383 ng/L (interquartile range, 977–2052 ng/L). Annual rates of stroke or systemic embolism ranged from 0.9% to 2.03% (P<0.001); of major bleeding, from 1.22% to 4.53% (P<0.001); and of mortality, from 1.34% to 7.19% (P<0.001) in the lowest compared with the highest GDF-15 quartile. The prognostic information provided by GDF-15 was independent of clinical characteristics and clinical risk scores. Adjustment for the other cardiac biomarkers attenuated the prognostic value for stroke, whereas the prognostic value for mortality and major bleeding remained. Apixaban consistently reduced stroke, mortality, and bleeding, regardless of GDF-15 levels. Conclusions— GDF-15 is a risk factor for major bleeding, mortality, and stroke in atrial fibrillation. The prognostic value for major bleeding and death remained even in the presence of N-terminal pro-brain natriuretic peptide and high-sensitivity troponin I. Clinical Trial Registration— URL: http://www.clinicaltrials.gov. Unique identifier: NCT00412984.

High-sensitivity troponin T and risk stratification in patients with atrial fibrillation during treatment with apixaban or warfarin.

OBJECTIVES The aim of this study was to evaluate the prognostic value of high-sensitivity troponin T (hs-TnT) in addition to clinical risk factors and the CHA2DS2VASc (congestive heart failure, hypertension, 75 years of age and older, diabetes mellitus, previous stroke or transient ischemic attack, vascular disease, 65 to 74 years of age, female) risk score in patients with atrial fibrillation (AF). BACKGROUND The level of troponin is a powerful predictor of cardiovascular events and mortality. METHODS A total of 14,897 patients with AF were randomized to treatment with apixaban or warfarin in the ARISTOTLE (Apixaban for the Prevention of Stroke in Subjects With Atrial Fibrillation) trial. The associations between baseline hs-TnT levels and outcomes were evaluated using adjusted Cox regression models. RESULTS Levels of hs-TnT were measurable in 93.5% of patients; 75% had levels >7.5 ng/l, 50% had levels >11.0 ng/l, and 25% had levels >16.7 ng/l. During a median 1.9-year period, the annual rates of stroke or systemic embolism ranged from 0.87% in the lowest hs-TnT quartile to 2.13% in the highest hs-TnT quartile (adjusted hazard ratio [HR]: 1.94; 95% confidence interval [CI]: 1.35 to 2.78; p = 0.0010). The annual rates in the corresponding groups ranged from 0.46% to 4.24% (adjusted HR: 4.31; 95% CI: 2.91 to 6.37; p < 0.0001) for cardiac death and from 1.26% to 4.21% (adjusted HR: 1.91; 95% CI: 1.43 to 2.56; p = 0.0001) for major bleeding. Adding hs-TnT levels to the CHA2DS2VASc score improved the C statistic from 0.620 to 0.635 for stroke or systemic embolism (p = 0.0226), from 0.592 to 0.711 for cardiac death (p < 0.0001), and from 0.591 to 0.629 for major bleeding (p < 0.0001). Apixaban reduced rates of stroke, mortality, and bleeding regardless of the hs-TnT level. CONCLUSIONS Levels of hs-TnT are often elevated in patients with AF. The hs-TnT level is independently associated with an increased risk of stroke, cardiac death, and major bleeding and improves risk stratification beyond the CHA2DS2VASc risk score. The benefits of apixaban as compared with warfarin are consistent regardless of the hs-TnT level. (Apixaban for the Prevention of Stroke in Subjects With Atrial Fibrillation [ARISTOTLE]; NCT00412984).