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BackgroundDyslipidemia is a major risk factor for cardiovascular events. The prognostic importance of lipoproteins in patients with atrial fibrillation is not well understood. We aimed to explore the association between apolipoprotein A1 (ApoA1) and B (ApoB) and cardiovascular events in patients with atrial fibrillation receiving oral anticoagulation. Methods and ResultsUsing data from the ARISTOTLE (Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation) trial, ApoA1 and ApoB plasma levels were measured at baseline in 14884 atrial fibrillation patients. Median length of follow-up was 1.9years. Relationships between continuous levels of ApoA1 and ApoB and clinical outcomes were evaluated using Cox models adjusted for cardiovascular risk factors, medication including statins, and cardiovascular biomarkers. A composite ischemic outcome (ischemic stroke, systemic embolism, myocardial infarction, and cardiovascular death) was used as the primary end point. Median (25th, 75th) ApoA1 and ApoB levels were 1.10 (0.93, 1.30) and 0.70g/L (0.55, 0.85), respectively. In adjusted analyses, higher levels of ApoA1 were independently associated with a lower risk of the composite ischemic outcome (hazard ratio, 0.81; P<0.0001). Similar results were observed for the individual components of the composite outcome. ApoB was not significantly associated with the composite ischemic outcome (P=0.8240). Neither apolipoprotein was significantly associated with major bleeding. There was no interaction between lipoproteins and randomized treatment for the primary outcome (both P values 0.2448). ConclusionsIn patients with atrial fibrillation on oral anticoagulation, higher levels of ApoA1 were independently associated with lower risk of ischemic cardiovascular outcomes. Investigating therapies targeting dyslipidemia may thus be useful to improve cardiovascular outcomes in patients with atrial fibrillation. Clinical Trial RegistrationURL: . Unique identifier: NCT00412984.

Objectives Growth differentiation factor 15 (GDF-15) is a biomarker independently associated with bleeding and death in anticoagulated patients with atrial fibrillation (AF). GDF-15 is also used as one component in the more precise biomarker-based ABC (age, biomarkers, clinical history)-AF-bleeding and ABC-AF-death risk scores. Data from large trials indicate a geographic variability in regard to overall outcomes, including bleeding and mortality risk. Our aim was to assess the consistency of the association between GDF-15, ABC-AF-bleeding score and ABC-AF-death score, with major bleeding and death, across world geographic regions. Methods Data were available from 14 767 patients with AF from the Apixaban for Reduction in Stroke and Other Thromboembolic Events in Atrial Fibrillation (ARISTOTLE) trial and 8651 patients with AF from the Randomized Evaluation of Long-Term Anticoagulation Therapy (RE-LY) trial in this cohort study. GDF-15 was analysed from plasma samples obtained at randomisation. The geographical consistency of the associations between outcomes and GDF-15, ABC-AF-bleeding score and ABC-AF-death scores were assessed by Cox-regression models including interactions with predefined geographical region. Results GDF-15 and the ABC-AF-bleeding score were associated with major bleeding in both trials across regions (p<0.0001). Similarly, GDF-15 and the ABC-AFdeath score were associated with all-cause mortality in both trials across regions (p<0.0001). Overall, the association between GDF-15, the ABC-AF-bleeding score and ABC-AF-death risk score with major bleeding and death was consistent across regions in both ARISTOTLE and the RE-LY trial cohorts. The ABC-AF-bleeding and ABC-AF-death risk scores were consistent regarding discriminative ability when comparing geographic regions in both trial cohorts. The C-indices ranged from 0.649 to 0.760 for the ABC-AF-bleeding and from 0.677 to 0.806 for the ABC-AF-death score by different geographic regions. Conclusions In patients with AF on anticoagulation, GDF-15 and the biomarker-based ABC-AF-bleeding and ABC-AF-death risk scores are consistently associated with respectively increased risk of major bleeding and death and have similar prognostic value across world geographic regions.

AIMS: Atrial fibrillation (AF) is associated with higher mortality. Biomarkers may improve the understanding of key pathophysiologic processes in AF that lead to death. Using a new multiplex analytic technique, we explored the association between 268 biomarkers and cardiovascular (CV) death in anticoagulated patients with AF.

METHODS AND RESULTS: A case-cohort design with 1.8 -1.9 years follow-up. The identification cohort included 517 cases and 4057 randomly selected patients from ARISTOTLE. The validation cohort included 277 cases and 1042 randomly selected controls from RE-LY. Plasma collected at randomization was analyzed with conventional immunoassays and the OLINK proximity extension assay-panels; CVDII, CVDIII, and Inflammation. Association between biomarkers and CV-death was evaluated using Random Survival Forest, Boruta and adjusted Cox-regression analyses.The biomarkers most strongly and consistently associated with CV-death were (hazard ratio for inter-quartile comparison [95% CI]): N-terminal pro-B-type natriuretic peptide (NT-proBNP; 1.63 [1.37-1.93]), cardiac troponin T (cTnT-hs; 1.60[1.35-1.88]), interleukin-6 (IL-6; 1.29[1.13-1.47]), growth differentiation factor-15 (GDF-15; 1.30[1.10-1.53]) fibroblast growth factor 23 (FGF-23; 1.21[1.10-1.33]), urokinase receptor (uPAR; 1.38[1.16-1.64]), trefoil factor 3 (TFF3; 1.27[1.10-1.46]), tumor necrosis factor receptor 1 (TNFR1; 1.21[1.01-1.45]), TNF-related apoptosis-inducing ligand receptor 2 (TRAILR2; 1.18[1.04-1.34]) and cathepsin L1 (CTSL1; 1.22[1.07-1.39]).

CONCLUSION: In this comprehensive screening of 268 biomarkers in anticoagulated patients with AF the underlying mechanisms most strongly associated with CV-death were cardiorenal dysfunction (NT-proBNP, cTnT-hs, CTSL1, TFF3), oxidative stress (GDF-15), inflammation (IL-6, GDF-15), calcium balance, vascular and renal dysfunction (FGF-23), fibrinolysis (suPAR) and apoptosis (TNFR1, TRAILR2). These findings provide novel insights into pathophysiologic aspects associated with CV-death in AF.

TRANSLATIONAL PERSPECTIVE: In patients with AF there is an unmet need for better understanding of the pathophysiological processes involved with CV-death. Using a targeted proteomic approach, 10 biomarkers were identified as having a strong association with CV-death. The identified biomarkers reflect several biological pathways involved with CV-death in AF. The present study provides valuable insights into important processes involved with CV-death in patients with AF and may facilitate the identification of important risk factors for death, thus allowing for earlier intervention and possibly even for targeted therapy to reduce AF-related mortality.

CLINICALTRIALS.GOV IDENTIFIER: NCT00412984 and NCT00262600.

Background

Atrial fibrillation (AF) is associated with heart failure (HF) with a complex cause and effect relationship. We performed multiplex screening of plasma proteins to identify biomarkers and pathways associated with HF subsequent hospitalization, as well as potential pathophysiological differences between HFrEF and HFpEF at baseline in patients with AF.

Methods

Using a case-cohort design of patients with AF from the ARISTOTLE trial, the study cohort consisted of 596 cases of HF hospitalizations during follow-up and 4029 randomly selected controls without HF hospitalization. Plasma obtained at randomization was analysed with conventional immunoassays and proximity extension assay panels. Biomarker associations with HF hospitalization were evaluated using Random Survival Forest, Boruta and Cox-regression analyses. Associations between biomarkers and HF subtype were evaluated with Wilcoxon−Mann−Whitney test with Bonferroni-Holm adjustment for multiplicity.

Results

The biomarkers most strongly associated with increased risk of HF hospitalization were NT-proBNP, BNP, cTnT‐hs, FGF-23, spon1, IGFBP-7, u-par, OPN, PTX3 and TR (all P< 0.01) and TRAP, TRAIL and GIF with lower risk. In multiplicity adjusted comparison of HFrEF versus HFpEF, levels of NT-proBNP, BNP, cTnT‐hs, renin, ACE-2, GDF-15 and IL-6 were higher in HFrEF, whereas levels of SCF and leptin were higher in HFpEF (all p<0.05).

Conclusions

Out of 268 evaluated biomarkers, this study identified biomarkers representing different mechanisms strongly associated with subsequent HF hospitalization. HFrEF was more strongly associated with cardiorenal dysfunction and inflammation markers, while HFpEF was associated with adipose metabolism and tissue repair proteins.