Use of non-vitamin K antagonist oral anticoagulants in atrial fibrillation patients: insights from a specialist atrial fibrillation clinic.

Non-vitamin K antagonist oral anticoagulants (NOACs) are broadly preferable to vitamin K antagonists (VKAs) for stroke prevention in non-valvular atrial fibrillation (AF) given their overall net clinical benefit. We report an audit of the profile of OAC usage and adverse events in patients attending a specialist AF clinic. Patients attending our specialist AF clinic who were commenced on NOACs for SPAF between January 2013 and August 2014 were included and electronic medical records were retrospectively reviewed between August 2014 and November 2014, to collect demographic, clinical and outcome data. Outcomes included cerebrovascular and bleeding events, death, switching between NOACs or to VKA, dose changes, cessation of NOACs and the reasons for these. To provide perspective, descriptive comparisons were made with a historical cohort of warfarin users attending the specialist AF clinic prior to the introduction of NOACs. We report data on 813 patients as follows: (i) 233 consecutive patients (mean (standard deviation) age 74 (10) years, 45.1% female) initiated on NOACs, with median (interquartile range) CHA2 DS2 -VASc score 3 (2-5) and HAS-BLED score 1 (1-2); and (ii) a historical cohort of 580 patients on warfarin (mean (SD) age 75 (10) years, 42.1% female) with broadly similar demographics. Overall, 54.5% (127/233) were started on rivaroxaban, 22.7% (53/233) on dabigatran and 22.7% on apixaban. Two patients experienced a transient ischaemic attack; 31 patients (13%) contributed to 37 documented bleeding events of which five bleeds (in four patients, 1.7%) were classified as major. There were seven deaths; cause of death was not available for three and the others were not related to NOACs. Eighteen (7.7%) patients switched NOACs, 2 (0.9%) patients switched to warfarin and 8 (3.4%) had their NOACs stopped. There were no ischaemic strokes in the NOAC cohort, compared with nine in the warfarin cohort, with a similar rate of major bleeding (1.7% for NOACs and 1.6% for warfarin). There were more gastrointestinal haemorrhages in the NOAC cohort (3.4% vs. 0.7% with warfarin). In this specialist AF clinic, patients prescribed NOACs had a favourable adverse event profile with good efficacy for stroke prevention, with a low rate of cessation or switch to warfarin.

Lee SI ，Sayers M ，Lip GY ，Lane DA ... -  《-》

Vitamin K and non-vitamin K antagonist oral anticoagulants for non-valvular atrial fibrillation in real-life.

Current guidelines recommend vitamin K antagonists (VKAs) or non-vitamin K antagonist oral anticoagulants (NOACs) for stroke prevention in patients with non-valvular atrial fibrillation (AF). We compared the clinical features of consecutive in- and out-patients with non-valvular AF newly-treated with NOACs or on treatment with VKAs. Overall, 1314 patients newly-treated with NOACs and 1024 on treatment with VKAs were included in the study. The mean CHA2DS2-VASc score was 4.3±1.5 and 4.0±1.5 and the mean HAS-BLED score was 2.8±1.2 and 2.2±1.1 in the two groups, respectively (both p<0.001). Hypertension, previous stroke, female gender, vascular diseases and previous bleeding were more prevalent in NOACs patients. Renal failure, age ≥75years and congestive heart failure were more prevalent in VKAs patients. Among NOACs patients, 438 were given dabigatran, 463 rivaroxaban and 413 apixaban (33%, 35% and 31%, respectively). The mean CHA2DS2-VASc and HAS-BLED scores were higher in rivaroxaban or apixaban patients compared with dabigatran (both p<0.001) and VKAs patients (both p<0.001). A lower mean age was observed in patients newly-treated with dabigatran. Patients newly-treated with reduced doses of NOACs (599 patients, 45.5%) had a higher CHA2DS2-VASc (4.8±1.4 vs. 3.9±1.5 vs. 4.0±1.5) and HAS-BLED (2.9±1.1 vs. 2.8±1.2 vs. 2.2±1.1) scores compared with those treated with regular doses of NOACs or VKAs. Patients given rivaroxaban and apixaban in clinical practice have a higher thrombotic and hemorrhagic risk in comparison with patients given dabigatran or VKAs. A considerable proportion of patients receive reduced doses of NOACs.

Giustozzi M ，Vedovati MC ，Verdecchia P ，Pierpaoli L ，Verso M ，Conti S ，Cianella F ，Marchesini E ，Filippucci E ，Agnelli G ，Becattini C ... -  《-》

Initiation of anticoagulation in atrial fibrillation: which factors are associated with choice of anticoagulant?

The use of non-vitamin K antagonist oral anticoagulants (NOACs) for stroke prophylaxis in atrial fibrillation (AF) is increasing rapidly. We compared characteristics of AF patients initiated on NOACs versus vitamin K antagonists (VKAs). Using Danish nationwide registry data, we identified AF patients initiating either a VKA or a NOAC from 22 August 2011 until 30 September 2016. We compared patient characteristics including age, gender, comorbidities, concomitant pharmacotherapy and CHA2 DS2 -VASc and HAS-BLED scores in patients initiated on a VKA, dabigatran, rivaroxaban or apixaban. Differences were examined using multivariable logistic regression models. The study population comprised 51 981 AF patients of whom 19 989 (38.5%) were initiated on a VKA, 13 242 (25.5%) on dabigatran, 8475 (16.3%) on rivaroxaban and 10 275 (19.8%) on apixaban. Those patients initiated on apixaban had higher mean ± SD CHA2 DS2 -VASc scores than those initiated on a VKA (3.1 ± 1.6 vs. 2.9 ± 1.6). Those initiated on dabigatran had lower mean CHA2 DS2 -VASc scores (2.7 ± 1.6) than all other groups. Patients with a history of a prior stroke were significantly more likely to be initiated on a NOAC compared with a VKA [odds ratio (OR) 1.35, 95% confidence interval (CI) 1.28-1.43]. By contrast, patients with a history of myocardial infarction were less likely to be initiated on a NOAC compared with a VKA (OR 0.72, 95% CI 0.67-0.77). Atrial fibrillation patients who were initiated on apixaban had higher stroke risk scores than patients initiated on VKAs. Interestingly, opposite results were found for dabigatran.

Gundlund A ，Staerk L ，Fosbøl EL ，Gadsbøll K ，Sindet-Pedersen C ，Bonde AN ，Gislason GH ，Olesen JB ... -  《-》

Is the prescription right? A review of non-vitamin K antagonist anticoagulant (NOAC) prescriptions in patients with non-valvular atrial fibrillation. Safe prescribing in atrial fibrillation and evaluation of non-vitamin K oral anticoagulants in stroke pre

Pharithi RB ，Ranganathan D ，O'Brien J ，Egom EE ，Burke C ，Ryan D ，McAuliffe C ，Vaughan M ，Coughlan T ，Morrissey E ，McHugh J ，Moore D ，Collins R ... -  《-》

Non-vitamin K Oral Anticoagulants Versus Warfarin for Patients with Atrial Fibrillation: Absolute Benefit and Harm Assessments Yield Novel Insights.

Benefits and/or harms (including costs) of non-vitamin K oral anticoagulants (NOACs) versus warfarin therapy need appreciation in relative and absolute terms. Accordingly, we derived clinically relevant relative and absolute benefit/harm parameters for NOACs (apixaban, dabigatran, rivaroxaban, edoxaban) compared to warfarin from four clinical trials involving atrial fibrillation (AF) patients. For each trial, we tabulated patient numbers enduring four important outcomes and calculated unadjusted relative risk reduction (RRR) and number needed to treat (NNT)/year values (and 95% confidence intervals) for the NAOC compared to warfarin. These outcomes were as follows: stroke/systemic embolism (primary endpoint), hemorrhagic stroke, major bleeds, and death. We also addressed drug acquisition costs. Each NOAC was noninferior to warfarin for primary-outcome prevention; RRRs were 12-33% and NNT/year values were 182-481, and all but one indicated statistically significant superiority. All the NOACs yielded statistically significant reductions in hemorrhagic stroke risk; RRRs were 42-74% and NNT/year values were 364-528. Major bleeding risk was comparable in both groups. Apixaban yielded a lower NNT/year for preventing death than for primary-outcome prevention. Compared to warfarin, NOAC acquisition costs were 70- to 140-fold greater. For the primary outcome, the absolute benefits of NOACs were modest (NNT/year values being large). Reduced hemorrhagic stroke rates with NOACs could be due to superior embolic infarct prevention and fewer consequential hemorrhagic transformations. Among apixaban recipients, the absolute mortality benefit exceeded that for the primary outcome, indicating prevention of additional unrelated deaths. The substantially greater NOAC acquisition costs need viewing against probable greater safety and the avoidance of monitoring bleeding risks.

Kumana CR ，Cheung BM ，Siu DC ，Tse HF ，Lauder IJ ... -  《-》