Prior Warfarin Use Research Articles

Post-discharge pharmacotherapy in people with atrial fibrillation hospitalised for acute myocardial infarction: an Australian cohort study 2018-2022.

Dual antiplatelet therapy with P2Y12 inhibitors (P2Y12i) and aspirin following acute myocardial infarction (AMI) prevents future ischaemic events. People with atrial fibrillation (AF) also require oral anticoagulants (OAC), increasing bleeding risk. Guidelines recommend post-discharge prescribing of direct OAC with clopidogrel and discontinuation of P2Y12i after 12 months, but little is known about use in clinical practice. To describe post-discharge use of OACs and P2Y12i in people with AF and a history of OAC use hospitalised for AMI. We identified 1,330 people hospitalised for AMI with a diagnosis of AF and history of OAC use in New South Wales, Australia, July 2018-June 2020. We identified three aspects of post-discharge antithrombotic medicine use with possible safety implications: (1) not being dispensed OACs; (2) dispensing OAC and P2Y12i combinations associated with increased bleeding (involving warfarin, ticagrelor or prasugrel); and (3) P2Y12i use longer than 12 months.After discharge, 74.3% of people were dispensed an OAC, 45.4% were dispensed a P2Y12i, and 35.8% were dispensed both. People with comorbid heart failure or cancer were less likely to receive OACs. Only 11.2% of people dispensed both an OAC and P2Y12i received combinations associated with increased bleeding; this was more common among people with chronic kidney disease or prior warfarin or statin use. 44.6% of people dispensed both medicines continued P2Y12i for over 12 months; this was more common in people who received a revascularisation or lived in areas of social disadvantage. We identified potential gaps in pharmacotherapy, including underuse of recommended therapies at discharge, use of combinations associated with increased bleeding, and P2Y12i use beyond 12 months. Prescribing vigilance across both hospital and community care is required.

Trends in prior antithrombotic medication and risk of in-hospital mortality after spontaneous intracerebral hemorrhage: the J-ICH registry

Spontaneous intracerebral hemorrhage (SICH) remains a devastating form of stroke. Prior use of antiplatelets or warfarin before SICH is associated with poor outcomes, but the effects of direct oral anticoagulants (DOACs) remain unclear. This study aimed to clarify trends in prior antithrombotic use and to assess the associations between prior use of antithrombotics and in-hospital mortality using a multicenter prospective registry in Japan. In total, 1085 patients were analyzed. Prior antithrombotic medication included antiplatelets in 14.2%, oral anticoagulants in 8.1%, and both in 1.8%. Prior warfarin use was significantly associated with in-hospital mortality (odds ratio [OR] 5.50, 95% confidence interval [CI] 1.30–23.26, P < 0.05) compared to no prior antithrombotic use. No such association was evident between prior DOAC use and no prior antithrombotic use (OR 1.34, 95% CI 0.44–4.05, P = 0.606). Concomitant use of antiplatelets and warfarin further increased the in-hospital mortality rate (37.5%) compared to warfarin alone (17.2%), but no such association was found for antiplatelets plus DOACs (8.3%) compared to DOACs alone (11.9%). Prior use of warfarin remains an independent risk factor for in-hospital mortality after SICH in the era of DOACs. Further strategies are warranted to reduce SICH among patients receiving oral anticoagulants and to prevent serious outcomes.

Providing Evidence for Dogma: Risk of Epistaxis After COVID-19 Nasal-Screening Swab.

There is anecdotal evidence SARS-CoV-2 (COVID) RT-PCR screening nasal swabs confer an elevated epistaxis risk. We aimed to assess the association between epistaxis and exposure to a COVID nasal swab. A matched pairs design was used. The study was performed in a single, integrated health care system. All patients who received a single COVID nasal swab at our institution between April 2020 and March 2021 were included. McNemar's test was used to compare rates of epistaxis between the 7 days following the index COVID swab (hazard period), and the 7 days preceding the index COVID swab (control period). Conditional logistic regression was used to evaluate sociodemographic and clinical risk factors for epistaxis. A total of 827,987 participants were included, with 1047 epistaxis encounters. The prevalence of epistaxis during the hazard and control periods were 0.08% and 0.04%, respectively. Swab exposure was associated with 1.92-fold odds of epistaxis during the hazard period (95% confidence interval [1.73, 2.12]). Older age, Asian/Pacific Islander (PI) (compared to white), male sex, hypertension, prior facial trauma, and warfarin or direct-acting oral anticoagulant use were also associated with significantly increased odds of epistaxis (p ≦ 0.01). COVID nasal swabs are associated with increased odds of epistaxis. Physicians should counsel patients, particularly those at the highest risk, including ahistory of prior facial trauma, anticoagulants/antiplatelets, or hypertension.

An unexpected case of non-uremic calciphylaxis in a patient with multiple risk factors.

A 58-year-old woman with a history of morbid obesity, asthma, and prior warfarin use presented to the hospital with shortness of breath and a three-month history of painful, ulcerated ulcers with retiform purpura of her bilateral distal extremities. A punch biopsy specimen demonstrated focal necrosis and hyalinization of the adipose tissue with subtle arteriolar calcium deposition, findings consistent with calciphylaxis. We discuss the presentation of non-uremic calciphylaxis and review the risk factors, pathophysiology, and interdisciplinary management approach of this rare disease.

Risks associated with prior oral anticoagulation use in hospitalized COVID-19 patients – A retrospective cohort study on 5392 patients from a tertiary centre

IntroductionThere are conflicting data on prior oral-anticoagulant (OAC) use and outcomes of hospitalized COVID-19 patients. Due to uncertainties regarding associated risks with the prior OAC use, we have investigated this issue in a large cohort of hospitalized COVID-19 patients from our institution. MethodsWe have retrospectively evaluated a total of 5392 consecutive COVID-19 patients hospitalized in our tertiary center institution in period 3/2020 to 6/2021. Majority of patients received low-molecular-weight-heparin thromboprophylaxis and corticosteroids during hospitalization. Patients' characteristics and clinical outcomes were documented as a part of a hospital registry project and were evaluated according to the prior non-OAC, warfarin and direct oral anticoagulants (DOAC) use. ResultsMedian age was 72 years, median Charlson comorbidity index (CCI) was 4 points. There were 56.2% male patients. Majority of patients had severe (70.5%) or critical (15.8%) COVID-19 on admission. A total of 84.8% patients did not receive prior OAC, 9% were previously anticoagulated with warfarin and 6.2% were previously anticoagulated with DOACs.In the multivariate regression analyses, prior warfarin use was associated increased in-hospital mortality (OR 1.24, P = 0.048) independently of older age (OR 2.12, P < 0.001), male sex (OR 1.27, P < 0.001), higher CCI (OR 1.26, P < 0.001) and severe or critical COVID-19 on admission (OR 22.66, P < 0.001). Prior DOAC use was associated with higher occurrence of major bleeding (OR 1.72, P = 0.045) independently of higher CCI (OR 1.08, P = 0.017). ConclusionPrior OAC use could be associated with worse clinical outcomes during COVID-19 hospitalization. These phenomena might be OAC type specific and persist after multivariate adjustments.

Evolution of and Evidence-Practice Gaps in Antithrombotic Management of Atrial Fibrillation Patients After Percutaneous Coronary Intervention

BackgroundThe management of atrial fibrillation and flutter (AF) patients undergoing percutaneous coronary intervention (PCI) has evolved rapidly in the past decade. We determine whether the publication of the 2016 Canadian Cardiovascular Society AF guidelines were associated with a shift in practice patterns. MethodsUsing Quebec provincial administrative database information for the period from 2010-2017, a retrospective cohort of patients with inpatient or outpatient coding for AF, who subsequently underwent PCI with placement of a coronary stent, was created and analyzed for the antithrombotic regimen received in the following year. Prescribing behavior was compared among 3 time periods (2010-2011, 2012-2015, 2016-2017), and use of antithrombotics was compared to guideline-predicted therapy using the χ2 test. Predictors of oral anticoagulation (OAC) prescription were identified using adjusted logistic regression. ResultsA total of 3740 AF patients undergoing PCI were included. The proportion of OAC prescription increased over time (2010-2011 = 51.4%; 2012-2015 = 54.3%; 2016-2017 = 56.6%; P = 0.13), with a significant increase in direct OAC prescription (P < 0.01). A substantial treatment gap in OAC prescription persisted after publication of the 2016 guidelines (56.6% observed vs 89.7% predicted; P < 0.01). Previous stroke, CHADS2 score, Charlson Comorbidity Index ≥ 4, and prior use of direct OAC or warfarin were predictors of being exposed to OAC claims; previous major bleeding, and low-dose acetylsalicylic acid or P2Y12 inhibitor use were predictors of not being exposed to OACs. ConclusionExpert guidance contributed to an increase in OAC prescription following PCI, but up to 2017, substantial further changes in practice patterns would have been required to achieve the recommended rates of OAC prescription.

Atrial fibrillation bleeding risk and prediction while treated with direct oral anticoagulants in warfarin-naïve or warfarin-experienced patients.

BackgroundIn patients with atrial fibrillation (AF) treated with direct oral anticoagulants (DOAC), bleeding risk scores provide only modest discrimination for major or intracranial bleeding. However, warfarin experience may impact HAS‐BLED (Hypertension, Abnormal renal/liver function, Stroke, Bleeding history or predisposition, Labile international normalized ratio, Elderly (>65 years), Drugs/alcohol concomitantly) score performance in patients evaluated for DOACs, as HAS‐BLED was derived and validated in warfarin cohorts.MethodsWe performed a retrospective cohort study of patients prescribed DOAC for AF in the Veterans Health Administration between 2010 and 2017. We determined modified HAS‐BLED score discrimination and calibration for bleeding, for patients treated with DOAC, stratified by prior warfarin exposure. We also determined the association between DOAC–warfarin‐naïve status to bleeding (nonintracranial and intracranial) with DOAC–warfarin‐experienced patients as reference.ResultsThe DOAC analysis cohort included 100, 492 patients with AF (age [mean ± SD]: 72.9 ± 9.6 years; 1.7% female; 90.1% White), of which 26, 760 patients (26.6%) and 73, 732 patients (73.4%) were warfarin experienced or naïve, respectively. HAS‐BLED discrimination for bleeds was modest for patients treated with DOAC, regardless of prior warfarin experience (concordance statistics: 0.53–0.59). For DOAC–warfarin‐naïve patients, as compared to DOAC–warfarin‐experienced patients, adjusted risk of intracranial bleeding was lower, while risk of nonintracranial bleeding was higher ( intracranial bleeding propensity adjusted with inverse probability of treatment weights [IPTWs]: hazard ratio [HR]: 0.86, 95% confidence interval [CI]: 0.78–0.95, p = .0040) (nonintracranial bleeding propensity adjusted with IPTW: HR: 1.15, 95% CI: 1.11–1.19, p < .0001).ConclusionPatients’ modified HAS‐BLED score at the time of DOAC initiation, regardless of prior warfarin use, provided only modest discrimination for intracranial and nonintracranial bleeds. These data argue against maintaining DOAC eligible patients on warfarin therapy regardless of modified HAS‐BLED score.

Abstract 10485: Case Fatality and Prior Anticoagulation in Patients with Atrial Fibrillation and First-Ever Ischemic Stroke

Introduction: Thromboprophylaxis of patients with atrial fibrillation (AF) has changed in the past decade. How the changes manifest in real life is yet less studied. This study describes 30-day case fatality and prior anticoagulation in a nationwide cohort of patients with AF and first-ever ischemic stroke during the past decade. Methods: FinACAF (Finnish Anticoagulation in Atrial Fibrillation) is a registry-linkage study. Data were collected from several nationwide registries. We followed patients with incident AF between 2009 and 2017 with first-ever ischemic stroke between January 2009 and November 2018. Cox regression model was used to estimate the associations between 30-day case fatality and oral anticoagulation (OAC) if purchased 90 days preceding the stroke, adjusting for age, sex, time of AF diagnosis relative to stroke (new-onset AF vs. prior diagnosis), and stroke year. Results: Altogether, 17,924 patients (55% female, median age 79 years with interquartile range 71-86) suffered from first-ever ischemic stroke. Crude 30-day case fatality was 15.4% (95% confidence interval 14.9-15.9, p=0.037). Prior NOAC (hazard ratio 0.69, 0.57-0.84, p&lt;0.001) and prior warfarin (0.78, 0.71-0.86, p&lt;0.001) usage were both associated with lower case fatality compared to those without any OAC in use. There was no significant difference between previous warfarin and NOAC usage. Older age and AF diagnosis registered before the stroke, as opposed to AF diagnosis first recognized together with stroke, were associated with higher case fatality. There was no significant difference between 30-day case fatality when comparing cases by the event year (1.00, 0.98-1.01, p=0.739). Conclusion: Previously recorded AF diagnosis was associated with higher 30-day case fatality, although prior use of warfarin and NOAC were associated with decreased mortality compared to no prior OAC use.

Predictors of Warfarin Time in Therapeutic Range after Continuous‐Flow Left Ventricular Assist Device

Patients with a continuous-flow left ventricular assist device (CF-LVAD) require anticoagulation with a vitamin K antagonist to prevent thromboembolic events. Fluctuations in the international normalized ratio are associated with both increased thrombotic and bleeding episodes. To date, risk factors for low time in therapeutic range (TTR) among ambulatory patients with a CF-LVAD have not been explored. A retrospective single-center analysis of 121 patients implanted with a CF-LVAD was performed. International normalized ratios were systematically recorded from the initial postdischarge outpatient visit to 12months of time on the device. Risk factors for low TTR were evaluated using a multivariable linear regression analysis. Each of the 21 independent variables was entered into a stepwise regression designed to minimize the Akaike information criteria. In the multivariable analysis, the model output revealed that every 1-year increase in age was associated with a 0.4% increase in TTR (p=0.008), and every 1 mile further from clinic was associated with a 0.08% increase in TTR (p=0.03). Female sex was associated with a 10.1% decrease in TTR (p=0.04), type 2 diabetes was associated with an 11.5% decrease in TTR (p=0.006), and prior warfarin use was associated with an 8.3% decrease in TTR (p=0.03). In CF-LVAD recipients receiving warfarin, increasing age and distance from clinic are independent predictors of higher TTR. Female sex, type 2 diabetes, and prior warfarin use are independent predictors of lower TTR.

Direct oral anticoagulant– versus vitamin K antagonist–related gastrointestinal bleeding: Insights from a nationwide cohort

The purpose of the study was to examine the association between the type of preceding oral anticoagulant use (warfarin or direct oral anticoagulants [DOACs]) and in-hospital mortality among patients admitted with gastrointestinal bleeding. In this observational cohort study, all patients admitted with a first-time gastrointestinal bleeding from January 2011 to March 2017 while receiving any oral anticoagulant therapy prior to admission were identified using data from Danish nationwide registries. The risk of in-hospital mortality according to type of oral anticoagulation therapy was examined by multivariable logistic regression models. Among 5,774 patients admitted with gastrointestinal bleeding (median age, 78 years [25th-75th percentile, 71-85 years]; 56.8% men), 2,038 (35.3%) were receiving DOACs and 3,736 (64.7%) were receiving warfarin prior to admission. The unadjusted in-hospital mortality rates were 7.5% for DOAC (7.2% for dabigatran, 6.4% for rivaroxaban, and 10.1% for apixaban) and 6.5% for warfarin. After adjustment for baseline demographic and clinical characteristics, there was no statistically significant difference in in-hospital mortality between prior use of any DOAC and warfarin (unadjusted odds ratio [OR] 1.18 [95% CI 0.95-1.45], adjusted OR 0.97 [95% CI 0.77-1.24]). Similar results were found for each individual DOAC as compared with warfarin (dabigatran: unadjusted OR 1.12 [95% CI 0.84-1.49], adjusted OR 0.96 [95% CI 0.71-1.30]); rivaroxaban: unadjusted OR 0.98 [95% CI 0.71-1.37], adjusted OR 0.84 [95% CI 0.59-1.21]; and apixaban: unadjusted OR 1.62 [95% CI 0.84-1.49], adjusted OR 1.22 [95% CI 0.83-1.79]). Among patients admitted with gastrointestinal bleeding, there was no statistically significant difference in in-hospital mortality between prior use of DOAC and warfarin.

Influence of warfarin on cardiac and cerebrovascular events following bioprosthetic aortic valve replacement: A nationwide cohort study

ObjectiveThe need for anticoagulation treatment following bioprosthetic aortic valve replacement remains controversial. We investigated the associations of warfarin treatment with the risks of major adverse cardiac and cerebrovascular events, including mortality, bleeding incidents, and reoperation requirement after bioprosthetic aortic valve replacement surgery. MethodsWe identified 1086 patients who received first bioprosthetic aortic valve replacement between 2001 and 2010 using Taiwan's National Health Insurance Database. Patients were excluded for prior use of warfarin, warfarin use for >3 months, dual valve procedures, prior valve surgeries, or concomitant surgeries. Enrolled patients were divided into 2 groups according to whether they were warfarin-naïve or received warfarin for <3 months postsurgery. After propensity score matching, 282 patients not receiving warfarin were matched to 282 patients receiving warfarin for <3 months. Patients were followed-up for minimum 36 months. ResultsPatients receiving warfarin were younger and showed less frequent kidney disease than those who did not use warfarin. The warfarin group demonstrated a gross decrease in major adverse cardiac and cerebrovascular events. Patients receiving warfarin for <30 days were at an even lower risk for major adverse cardiac and cerebrovascular events than those treated for ≥30 days. No significant difference in bleeding or reoperation risk was observed between warfarin users and warfarin nonusers. Similar findings remained after propensity-score matching but the benefit of short-term warfarin use diminished in a younger population. ConclusionsShort-term use of postoperative warfarin (especially <30 days) following bioprosthetic aortic valve replacement may be associated with a reduction in MACCE compared with nonuse.

Pre-stroke warfarin enhancement of collateralization in acute ischemic stroke: a retrospective study

BackgroundWarfarin therapies not only are used to prevent stroke in patients with high risk of cardioembolism such as patients with atrial fibrillation (AF) and rheumatic heart disease (RHD), but also was associated with lower stroke severity and more favorable functional outcomes in patients with acute ischemic stroke due to middle cerebral artery occlusion. It was speculated that pre-stroke warfarin may promote collateralization and result in reduced stroke severity. This study aimed to investigate the association between pre-stroke warfarin use and leptomeningeal collaterals in patients with acute ischemic stroke due to occlusion of the middle cerebral artery.MethodsWe enrolled consecutive acute ischemic stroke patients (occlusion of the middle cerebral artery within 24 h) with known history of AF and/or RHD at the neurology department of the West China Hospital from May 2011 to April 2017. Computed tomography angiography (CTA) before treatment was used to detect the thrombus. Regional leptomeningeal collateral (rLMC) score based on CTA images was used to assess collateral circulation. Prior use of warfarin was recorded. Univariate and multivariate analyses were performed to detect the association of prior warfarin use with the collateral circulation.ResultsA total of 120 patients were included; 29 (24.2%) were taking warfarin before stroke. The international normalized ratio (INR) in patients with prior warfarin use was 1.53 ± 1.00, compared with 1.02 ± 0.09 in patients without prior warfarin use (P < 0.001). Prior oral warfarin therapy was inversely associated with poor rLMC (OR = 0.07, 95%CI 0.01–0.44, P = 0.005). There were no associations between prior warfarin use and initial stroke severity or functional outcomes at 3 months.ConclusionWarfarin use seems improve collateralization in patients with acute stroke. However, clinical controlled studies should be used to verify this claim.

Factors Associated with Bleeding Events in Patients Receiving Rivaroxaban for Venous Thromboembolism: A Real World Experience

Introduction:Rivaroxaban is a target specific oral anticoagulant approved for treatment of deep venous thromboembolism (DVT), pulmonary embolism (PE) and risk reduction in patients with DVT/PE requiring continued anticoagulation. The XALIA study showed a reduced bleeding risk compared to standard anticoagulation therapy; however, there is paucity of data regarding correlates of bleeding risk amongst patients receiving rivaroxaban in the community setting. We aimed to investigate the clinical factors associated with bleeding events (BE) in patients receiving rivaroxaban for treatment of DVT/PE.Methods:A retrospective study was conducted at John H. Stroger, Jr. Hospital of Cook County. We screened the charts of 837 patients who received rivaroxaban from January 1, 2015 to April 01, 2018. Patients with DVT/PE were included in the study (n=271). Patients with atrial fibrillation and those receiving rivaroxaban for prophylaxis were excluded. Any reported BE was recorded as either major or minor bleeding event. Major BE was defined as events requiring hospitalization, blood transfusions or significant drop in hemoglobin (>2gm/dL). Rest of the BE were classified as minor BE. Socio-demographic and clinical factors were collected. Chi-square test and fisher exact test were used as the tests of trend. Multivariate logistic regression models were used to quantify the independent predictors. Odds ratios (OR) and adjusted odds ratios (aOR) with 95% confidence intervals (CI) were obtained.Results:The study included 271 patients, of which 68.3% were African-American, 14.4% were Caucasian, and 12.9% were Hispanic. Median age was 53 years and 60.9% patients were men. Bleeding events were reported in 11.4% (n=31) patients with 6.3% major bleeding events and 5.2% minor bleeding events. Only concurrent use of aspirin (23.8% vs. 9.2%; OR 3.10, 95% CI 1.34-7.17, P = 0.008) was significantly associated with bleeding events. None of the clinical parameters, like abnormal liver function tests (11.4%), cirrhosis (3.3%), chronic kidney disease stage 3 or worse (7.6%), prior use of warfarin (29.9%) or low molecular weight heparin (18.1%) were associated with bleeding events. In multivariate model adjusted for age, gender and race, concurrent use of aspirin (aOR 3.06, 95% CI 1.23-7.62, P = 0.017) remained independent predictor of bleeding events.Conclusion:In the community practice, aspirin (81mg or 325mg) is prescribed for cardio-protection. A recently concluded trial showed a better cardioprotective effect of combining rivaroxaban and aspirin, without increase in BE in patients with stable cardiovascular disease. However, such data is not evident in patients receiving rivaroxaban for DVT/PE. Our study shows an increased rate of bleeding events in such patients with concurrent use of aspirin. Our study population comprises of two-third African-American patients who are under-represented in the clinical trials. Based on our results we would suggest further investigation in safety of prescribing aspirin with rivaroxaban in patients with DVT/PE in prospective trials. DisclosuresNo relevant conflicts of interest to declare.

Association of Intracerebral Hemorrhage Among Patients Taking Non–Vitamin K Antagonist vs Vitamin K Antagonist Oral Anticoagulants With In-Hospital Mortality

Although non-vitamin K antagonist oral anticoagulants (NOACs) are increasingly used to prevent thromboembolic disease, there are limited data on NOAC-related intracerebral hemorrhage (ICH). To assess the association between preceding oral anticoagulant use (warfarin, NOACs, and no oral anticoagulants [OACs]) and in-hospital mortality among patients with ICH. Retrospective cohort study of 141 311 patients with ICH admitted from October 2013 to December 2016 to 1662 Get With The Guidelines-Stroke hospitals. Anticoagulation therapy before ICH, defined as any use of OACs within 7 days prior to hospital arrival. In-hospital mortality. Among 141 311 patients with ICH (mean [SD] age, 68.3 [15.3] years; 48.1% women), 15 036 (10.6%) were taking warfarin and 4918 (3.5%) were taking NOACs preceding ICH, and 39 585 (28.0%) and 5783 (4.1%) were taking concomitant single and dual antiplatelet agents, respectively. Patients with prior use of warfarin or NOACs were older and had higher prevalence of atrial fibrillation and prior stroke. Acute ICH stroke severity (measured by the National Institutes of Health Stroke Scale) was not significantly different across the 3 groups (median, 9 [interquartile range, 2-21] for warfarin, 8 [2-20] for NOACs, and 8 [2-19] for no OACs). The unadjusted in-hospital mortality rates were 32.6% for warfarin, 26.5% for NOACs, and 22.5% for no OACs. Compared with patients without prior use of OACs, the risk of in-hospital mortality was higher among patients with prior use of warfarin (adjusted risk difference [ARD], 9.0% [97.5% CI, 7.9% to 10.1%]; adjusted odds ratio [AOR], 1.62 [97.5% CI, 1.53 to 1.71]) and higher among patients with prior use of NOACs (ARD, 3.3% [97.5% CI, 1.7% to 4.8%]; AOR, 1.21 [97.5% CI, 1.11-1.32]). Compared with patients with prior use of warfarin, patients with prior use of NOACs had a lower risk of in-hospital mortality (ARD, -5.7% [97.5% CI, -7.3% to -4.2%]; AOR, 0.75 [97.5% CI, 0.69 to 0.81]). The difference in mortality between NOAC-treated patients and warfarin-treated patients was numerically greater among patients with prior use of dual antiplatelet agents (32.7% vs 47.1%; ARD, -15.0% [95.5% CI, -26.3% to -3.8%]; AOR, 0.50 [97.5% CI, 0.29 to 0.86]) than among those taking these agents without prior antiplatelet therapy (26.4% vs 31.7%; ARD, -5.0% [97.5% CI, -6.8% to -3.2%]; AOR, 0.77 [97.5% CI, 0.70 to 0.85]), although the interaction P value (.07) was not statistically significant. Among patients with ICH, prior use of NOACs or warfarin was associated with higher in-hospital mortality compared with no OACs. Prior use of NOACs, compared with prior use of warfarin, was associated with lower risk of in-hospital mortality.

A Vascular Complications Risk (VASCOR) score for patients undergoing invasive cardiac procedures in the catheterization laboratory setting: A prospective cohort study.

Vascular complications are still common in the catheterization laboratory setting. However, no risk scores for their prediction have been described. With a view to bridging this gap, the present study sought to develop and validate a score for prediction of vascular complications associated with arterial access in patients undergoing interventional cardiology procedures. This prospective multicenter cohort study included adult patients who underwent cardiac catheterization via the femoral or radial route. The outcomes of interest were: access site hematoma; major and minor bleeding; and retroperitoneal hemorrhage, pseudoaneurysm, or arteriovenous fistula requiring surgical repair. Past medical history as well as pre-procedural, intra-procedural, and post-procedural variables were collected. Patients were randomly allocated to the derivation or validation cohorts at a 2:1 ratio. The following equation constituted the score: (>6F introducer sheath×4.0)+(percutaneous coronary intervention×2.5)+(history of vascular complication after prior interventional cardiology procedure×2.0)+(prior use of warfarin or phenprocoumon×2.0)+(female sex×1.5)+(age⩾60 years×1.5). The maximum score is 13.5 points. A score dichotomized at ⩾3 (best cutoff for balancing sensitivity and specificity) was moderately accurate (sensitivity=0.66 (95% confidence interval: 0.59-0.73); specificity=0.59 (95% confidence interval: 0.56-0.61)). Patients with a score ⩾3 were at increased risk of complications (odds ratio: 2.95; 95% confidence interval: 2.22-3.91). This study yielded a score that is capable of predicting vascular complications and easily applied in daily practice by providers working in the catheterization laboratory setting.

Comparative effectiveness of dabigatran and rivaroxaban versus warfarin for the treatment of non-valvular atrial fibrillation

BackgroundEffectiveness data on novel oral anticoagulants (NOACs) versus warfarin for stroke prevention in non-valvular atrial fibrillation (NVAF) by prior warfarin use are limited. MethodsWe used data from the US MarketScan databases from 2009 to 2012. NVAF patients initiating dabigatran or rivaroxaban were matched with up to 5 warfarin users. Propensity score-adjusted Cox regression was used to calculate hazard ratios (HR) and 95% confidence intervals (95% CI) for relevant endpoints in NOACs versus warfarin users. Separate analyses were conducted to compare anticoagulant-naïve users of NOACs and those switching from warfarin. ResultsAmong 32,918 dabigatran, 3301 rivaroxaban, and 109,447 warfarin users with NVAF, 225 intracranial bleeds, 1035 ischemic strokes, 958 myocardial infarctions, and 1842 gastrointestinal bleeds were identified. Compared to warfarin users, patients initiating NOACs had similar ischemic stroke rates and lower intracranial bleeding rates, while the gastrointestinal bleeding rate was higher in dabigatran users than warfarin users. Associations of dabigatran with ischemic stroke risk differed between anticoagulant-naïve initiators and patients switching from warfarin; dabigatran was associated with lower ischemic stroke rates in naïve users (HR 0.65, 95% CI 0.52–0.82) but not in switchers (HR 1.20, 95% CI 0.95–1.51), compared to warfarin. Risk of stroke and bleeding was not different between rivaroxaban and warfarin users. ConclusionsReal-world effectiveness of NOACs (compared to warfarin) for diverse outcomes was comparable to efficacy reported in published clinical trials. However, harms and benefits of switching from warfarin to dabigatran need to be evaluated.

PCV62 - Patterns and Predictors of Discontinuation and Switch in Atrial Fibrillation Patients Treated with Non-Vitamin K Antagonist Oral Anticoagulants

Recent clinical trials have established non-vitamin K antagonist oral anticoagulants (NOACs) as viable alternatives to warfarin in stroke prevention for atrial fibrillation. A major challenge in routine clinical practice is the high rate of medication discontinuation and switching. There are currently few large studies offering estimates of drug persistence with NOACs. Moreover, little is known about what drives patients’ choice and behavior regarding patterns of long-term medication use. Using a large heterogeneous cohort of patients, we aimed to investigate the patterns and predictors of switch and discontinuation among patients initiating NOACs. We performed a retrospective cohort analysis using a large U.S. commercial insurance database, OptumLabs Data Warehouse. We identified 10,147 privately insured and Medicare Advantage patients with nonvalvular atrial fibrillation who initiated apixaban, dabigatran and rivaroxaban in 2013 and 2014, the time period when all three NOACs had become available in the U.S. Discontinuation of anticoagulation was defined as having at least 3 months of gap in days of supply of any oral anticoagulants. Two multivariable logistic regression models were performed to assess the risk factors related switch and discontinuation, respectively. Within one year of NOACs initiation, 13% of the patients switched to another oral anticoagulant, among whom the majority (64%) switched to warfarin. Nearly 40% of patients discontinued oral anticoagulants. Patients initiating apixaban were less likely to switch or discontinue compared to those initiating dabigatran or rivaroxaban. Other risk factors for switch include high out-of-pocket costs, prior warfarin use, and a stroke during follow up. Risk factors for discontinuation include high out-of-pocket costs, no prior warfarin exposure, and a major bleeding during follow up. Medication discontinuation and switching are common among patients treated with NOACs in routine clinical practice. Medication use may be affected by the choice of initial medication, out-of-pocket costs, and clinical events occurring during follow up.

Cost-effectiveness of edoxaban vs warfarin in patients with atrial fibrillation based on results of the ENGAGE AF–TIMI 48 trial

In 21,105 patients with atrial fibrillation (AF), the ENGAGE AF-TIMI 48 trial demonstrated that both higher dose (60mg/30mg dose reduced) and lower dose (30mg/15mg dose reduced) once-daily regimens of edoxaban were non-inferior to warfarin for the prevention of stroke or systemic embolism (SE), with significantly lower rates of bleeding and cardiovascular death. Higher dose edoxaban was associated with a greater reduction in the risk of ischemic stroke than lower dose edoxaban, and the FDA approved higher dose edoxaban in patients with creatinine clearance ≤95mL/min. This study evaluated the economic value of higher dose edoxaban vs warfarin based on data from patients in ENGAGE within the FDA-approved population. We assessed the cost-effectiveness of edoxaban vs warfarin over a lifetime horizon from the US healthcare system perspective using a Markov model based on a combination of ENGAGE AF-TIMI 48 trial data, US life tables, and published literature on the costs and long-term outcomes of non-fatal cardiovascular and bleeding events. Data from the ENGAGE AF-TIMI 48 trial were used to calculate age-adjusted event rates for warfarin and hazard ratios (HRs) for the relative impact of edoxaban on embolic and bleeding complications. Based on the wholesale acquisition price, edoxaban and warfarin were assumed to cost $9.24 and $0.36/day, respectively. For edoxaban vs warfarin, lifetime incremental costs and QALYs were $16,384 and 0.444, respectively, yielding an incremental cost-effectiveness ratio (ICER) of $36,862/QALY gained, using data from patients with creatinine clearance ≤95mL/min in ENGAGE AF-TIMI 48. ICERs were more favorable for patients without compared to those with prior warfarin use; ICERs differed minimally by CHADS2 score. Despite its higher acquisition cost, edoxaban is an economically attractive alternative to warfarin for the prevention of stroke and SE in patients with atrial fibrillation and creatinine clearance ≤95mL/min. These results were robust to variation of key model parameters, including assumptions regarding the cost and quality-of-life impact of stroke and bleeding events, and were favorable across both CHADS2 score stroke-risk categories.

Anemia predicts thromboembolic events, bleeding complications and mortality in patients with atrial fibrillation: insights from the RE‐LY trial

Anemia may predispose to thromboembolic events or bleeding in anticoagulated patients with atrial fibrillation (AF). To investigate whether anemia is associated with thromboembolic events and bleeding in patients with AF. We retrospectively analyzed the RE-LY trial database, which randomized 18113 patients with AF and a risk of stroke to receive dabigatran or warfarin for a median follow-up of 2years. Cox regression analysis was used to determine whether anemia predicted cardiovascular events and bleeding complications in these patients. Anemia was present in 12% of the population at baseline, and the presence of anemia was associated with a higher risk of thromboembolic cardiovascular events, including the composite endpoint of all-cause mortality or myocardial infarction (adjusted hazard ratio [HR]1.50, 95% confidence interval [CI]1.32-1.71) and the primary RE-LY outcome of stroke or systemic embolism (adjusted HR1.41, 95%CI1.12-1.78). Anemia was also associated with a higher risk of major bleeding complications (adjusted HR2.14, 95%CI1.87-2.46) and discontinuation of anticoagulants (adjusted HR1.40, 95%CI1.28-1.79). The association between anemia and outcome was similar irrespective of cardiovascular comorbidities, randomized treatment allocation, or prior use of warfarin. The incidence of events was lower in patients with transient anemia than in patients in whom anemia was sustained (adjusted HR0.66, 95%CI0.49-0.91). Anemia is associated with an increased risk of thromboembolic events, bleeding complications and mortality in anticoagulated patients with AF. These findings suggest that patients with anemia should be monitored closely during all types of anticoagulant treatment.

Impact of video technology on efficiency of pharmacist-provided anticoagulation counseling and patient comprehension.

Discharge anticoagulation counseling is important for ensuring patient comprehension and optimizing clinical outcomes. As pharmacy resources become increasingly limited, the impact of informational videos on the counseling process becomes more relevant. To evaluate differences in pharmacist time spent counseling and patient comprehension (measured by the Oral Anticoagulation Knowledge [OAK] test) between informational videos and traditional face-to-face (oral) counseling. This prospective, open, parallel-group study at an academic medical center randomized 40 individuals-17 warfarin-naïve ("New Start") and 23 with prior warfarin use ("Restart")-to receive warfarin discharge education by video or face-to-face counseling. "Teach-back" questions were used in both groups. Although overall pharmacist time was reduced in the video counseling group (P < 0.001), an interaction between prior warfarin use and counseling method (P = 0.012) suggests the difference between counseling methods was smaller in New Start participants. Following adjustment, mean total time was reduced 8.71 (95% CI = 5.15-12.26) minutes (adjusted P < 0.001) in Restart participants and 2.31 (-2.19 to 6.81) minutes (adjusted P = 0.472) in New Start participants receiving video counseling. Postcounseling OAK test scores did not differ. Age, gender, socioeconomic status, and years of education were not predictive of total time or OAK test score. Use of informational videos coupled with teach-back questions significantly reduced pharmacist time spent on anticoagulation counseling without compromising short-term patient comprehension, primarily in patients with prior warfarin use. Study results demonstrate that video technology provides an efficient method of anticoagulation counseling while achieving similar comprehension.