Trends in antiplatelet strategies 12-months following coronary stent placement in anticoagulated patients.

BACKGROUND: Antithrombotic guidelines for patients undergoing percutaneous coronary interventions (PCIs) and also requiring anticoagulant medications are evolving. This study describes changes to antithrombotic therapy and associated outcomes 12-months following PCI in patients requiring ongoing anticoagulation therapy. METHODS: Records of patients identified from queries of electronic medical records were manually reviewed to verify changes to antithrombotic therapy from discharge to 12-months and at 12-months following PCI, and episodes of major bleeding, clinically relevant non-major bleeding (CRNMB), major adverse cardiovascular or neurological events (MACNE), and all-cause mortality outcomes during an additional 6-months follow-up. RESULTS: Patients (n = 120) receiving anticoagulation therapy at 12-months post PCI were classified into the following groups according to antiplatelet therapy status: no antiplatelet therapy (n = 16), single antiplatelet therapy (SAPT) (n = 85), and dual antiplatelet therapy (DAPT) (n = 19). Between 12- and 18-months following PCI there were 2 major bleeds, 7 CRNMB, 6 MACNE, 2 venous thromboembolisms, and 5 deaths. All but one bleeding episode occurred in the SAPT group. The odds of remaining on DAPT at 12-months were higher in patients who had PCI for acute coronary syndrome (odds ratio [OR] 2.91, 95% confidence interval [CI] 0.96, 8.77), and in those experiencing MACNE in the 12-months following PCI (OR 1.95, 95% CI 0.67, 5.66), but these associations were not statistically significant. CONCLUSION: Most anticoagulated patients were continued on antiplatelet therapy 12-months post PCI. Bleeding was numerically more common in anticoagulated patients continuing SAPT therapy beyond 12 months. There was significant variability in antithrombotic prescribing patterns 12-months post PCI suggesting a potential opportunity for standardizing care in this patient population.

Antiplatelet therapy indication in patients also prescribed direct oral anticoagulants.

Direct oral anticoagulants (DOACs) are standard of care for venous thromboembolism (VTE) treatment and stroke prevention in atrial fibrillation (AF). Adding antiplatelet therapy (APT) to an oral anticoagulant (OAC) causes a 2-fold increase in major bleeding. As such, recent guidelines recommend limiting the duration and indication of combined therapy in patients already on an OAC. Despite these recommendations, approximately one-third of anticoagulated patients are prescribed concomitant APT. University of Utah Health patients receiving DOAC + APT between August 1, 2019 and November 30, 2019 were included. These were categorized into four groups by APT indication: primary atherosclerotic cardiovascular disease (ASCVD) prevention, ASCVD-no percutaneous coronary intervention (PCI), ASCVD-PCI ≤ 12 months prior, ASCVD-PCI > 12 months prior. The primary outcome was the proportion of DOAC patients receiving concomitant APT for each indication. During the study period, 347 patients received DOAC + APT, primarily for AF (59.1%) or VTE (33.1%), and the most common DOAC was apixaban (76.7%).The most common indication for APT was ASCVD-no PCI (47.3%), followed by ASCVD-PCI > 12 months prior (30.8%), primary ASCVD prevention (18.7%), and ASCVD-PCI ≤ 12 months prior (1.7%). Five patients (1.4%) were on APT with unclear indication. Based on recent guidelines limiting indications and duration of APT added to anticoagulation, over 95% of patients in this single-center study warranted re-assessment of APT indication, with stable ASCVD and primary prevention being prime targets for APT de-prescribing. This study highlights the tremendous potential to improve patient safety and reduce bleeding harm.

Implementation and evaluation of a warfarin patient self-management (PSM) program among experienced patients in a U.S. academic health system.

Warfarin patient self-management (PSM) is when a patient independently manages their warfarin therapy using a decision-support tool provided by their anticoagulation provider. Clinical trials of PSM, conducted predominantly in Europe, have consistently demonstrated superior efficacy without compromising safety. However, the evidence-based practice of PSM is rarely utilized in the United States (U.S.). We describe initiatives completed to implement a successful PSM program among experienced warfarin-taking patients in a U.S. academic health system by overcoming perceived barriers. The results showed PSM resulted in similar or improved INR control, and an estimated 68% reduction in pharmacist workload.

A scoping review of direct oral anticoagulant ambulatory management practices.

Models of care for managing direct oral anticoagulant (DOAC) therapy are evolving. Little is known of what services are provided by anticoagulation managements services (AMS) for DOACs, or what necessitates comprehensive DOAC management and what differentiates it from usual care. The purpose of this scoping review was to describe services, management, or monitoring of DOACs distinct from prescriber-managed or usual care of DOACs. This scoping review reported followed the 2018 Preferred Reporting Items for Systematic Review and Meta-Analyses extension for scoping reviews (PRISMA-ScR). We searched PubMed, CINAHL, and EMBASE from inception to November 2020 to identify articles of interest. No language restriction was applied. Articles were included if they provided a description of DOAC management services, and described longitudinal anticoagulation follow-up that occurred in ambulatory care, community, or outpatient-related settings. Data was extracted from a total of 23 articles. The specific types of DOAC management interventions provided varied across the included studies. Nearly all studies described some form of DOAC therapy appropriateness assessment. Other common interventions included assessments of DOAC therapy compliance, adverse event triage and management, assessment of DOAC dosing appropriateness, periprocedural management of DOAC therapy, educational interventions, and renal function monitoring. A variety of DOAC management interventions were identified, but additional studies are needed to help health systems decide whether specific interventions performed by dedicated services are preferred over the usual care provided by clinicians prescribing DOAC therapy.

Effectiveness and safety of direct oral anticoagulants in patients with venous thromboembolism and creatinine clearance < 30 mL/min.

The few studies that compared direct oral anticoagulants (DOAC) vs. warfarin in the setting of advanced renal insufficiency have focused on patients with atrial fibrillation. The purpose of this observational, matched, cohort study of patients was to assess the effectiveness and safety of DOAC vs. warfarin for the treatment of venous thromboembolism (VTE) among patients with a creatinine clearance (CrCl) < 30 mL/min. This observational, cohort study included patients with VTE and CrCl < 30 mL/min who were newly initiated on a DOAC or warfarin between January 1, 2016 and December 31, 2020. DOAC patients were matched up to 1:2 to warfarin patients. Primary outcome was a composite of recurrent VTE, clinically-relevant bleeding, ischemic stroke, and all-cause mortality. Adjusted conditional, multivariate Cox proportional hazards modeling was used to assess outcomes. 626 DOAC patients were matched to 1071 warfarin patients. DOAC patients had a higher mean age, higher mean baseline CrCl, and were less likely to have been receiving dialysis. There was no statistically significant difference in the composite outcome between groups (adjusted hazard ratio [aHR] 1.13, 95% confidence interval [CI] 0.87-1.47) or in the individual components of the composite (all HR 95% CI crossed 1.00). Identification of statistically non-significant rates of bleeding and thromboembolic outcomes suggest that the use of DOAC or warfarin is reasonable in patients with VTE and CrCl < 30 mL/min.

Randomized evaluation of decision support interventions for atrial fibrillation: Rationale and design of the RED-AF study.

BACKGROUND: Shared decision making (SDM) improves the likelihood that patients will receive care in a manner consistent with their priorities. To facilitate SDM, decision aids (DA) are commonly used, both to prepare a patient before their clinician visit, as well as to facilitate discussion during the visit. However, the relative efficacy of patient-focused or encounter-based DAs on SDM and patient outcomes remains largely unknown. We aim to directly estimate the comparative effectiveness of two DA's on SDM observed in encounters to discuss stroke prevention strategies in patients with atrial fibrillation (AF). METHODS: The study aims to recruit 1200 adult patients with non-valvular AF who qualify for anticoagulation therapy, and their clinicians who manage stroke prevention strategies, in a 2x2 cluster randomized multi-center trial at six sites. Two DA's were developed as interactive, online, non-linear tools: a patient decision aid (PDA) to be used by patients before the encounter, and an encounter decision aid (EDA) to be used by clinicians with their patients during the encounter. Patients will be randomized to PDA or usual care; clinicians will be randomized to EDA or usual care. RESULTS: Primary outcomes are quality of SDM, patient decision making, and patient knowledge. Secondary outcomes include anticoagulation choice, adherence, and clinical events. CONCLUSION: This trial is the first randomized, head-to-head comparison of the effects of an EDA versus a PDA on SDM. Our results will help to inform future SDM interventions to improve patients' AF outcomes and experiences with stroke prevention strategies.

Replacement of traditional prothrombin time monitoring with the new Fiix prothrombin time increases the efficacy of warfarin without increasing bleeding. A review article.

The antithrombotic effect of vitamin K antagonists (VKA) depends on controlled lowering of the activity of factors (F) II and X whereas reductions in FVII and FIX play little role. PT-INR based monitoring, however, is highly influenced by FVII, which has the shortest half-life of vitamin K-dependent coagulation factors. Hence, variability in the anticoagulant effect of VKA may be partly secondary to an inherent flaw of the traditional monitoring test itself. The Fiix prothrombin time (Fiix-PT) is a novel test that is only sensitive to reductions in FII and FX and is intended to stabilize the VKA effect. Two clinical studies have now demonstrated that when warfarin is monitored with the Fiix-PT based normalized ratio (Fiix-NR) instead of PT-INR, anticoagulation is stabilized and less testing and fewer dose adjustments are needed. Furthermore, the relative risk of thromboembolism was reduced by 50-56% in these studies without an increase in major bleeding.

Comparative effectiveness and safety of direct acting oral anticoagulants in nonvalvular atrial fibrillation for stroke prevention: a systematic review and meta-analysis.

PURPOSE: To systematically review available evidence of indirect comparisons from RCTs and direct comparisons from observational studies regarding the comparative effectiveness and safety of DOACs in patients with AF. METHODS: Electronic databases including EMBASE, MEDLINE, and PUBMED were searched up to June 5th, 2020. Primary endpoints included effectiveness (stroke or systemic embolism [SE]) and safety (major bleeding) outcomes. Bucher methods and random-effects models were conducted for indirect and direct comparisons among DOACs, respectively. Ranking probability analyses and the number needed to treat for net effect (NNTnet) were applied. RESULTS: A total of 36 studies, involving 7 RCTs (n = 60,292 patients) and 29 observational studies (n = 1,164,821 patients), were included for analyses. Regarding the risk of stroke/SE, no significant differences were found from indirect comparisons of RCTs among the DOACs. For major bleeding, apixaban tended to be safer than rivaroxaban and dabigatran based on both direct and indirect comparisons (all p < 0.05; evidence quality: very low to moderate). Ranking probability analysis showed that apixaban had a high probability of being the best treatment in decreased risk of stroke/SE and major bleeding (80.30% and 91.30%, respectively). Likewise, apixaban was found to have the highest net clinical benefit (0.02, 95% CI: 0.014-0.029) and smallest NNTnet (48, 95% CI: 35-74). CONCLUSIONS: Apixaban appeared to have a favorable effectiveness-safety profile compared with the other DOACs in AF for stroke prevention, based on evidence from both direct and indirect comparisons. However, additional high-quality evidence is needed to support firm recommendations on clinical decision-making.

Anticoagulant therapy management of venous thromboembolism recurrence occurring during anticoagulant therapy: a descriptive study.

Limited evidence exists regarding management of recurrent venous thromboembolism (VTE) that occurs during anticoagulant therapy. We aimed to describe patient characteristics, drug therapy management, and outcomes of patients with VTE recurrence during anticoagulant therapy. We identified 30 relevant episodes of VTE recurrence. Mean age was 48.9 (15.9) years, 56.7% were male, and 93.3% were White. Common VTE risk factors included cancer (46.6%), recent surgery (33.3%), and prolonged immobility (30.0%). At the time of recurrent VTE, 40.0% were receiving enoxaparin, 30.0% warfarin, and 23.3% direct oral anticoagulants. Potential causes for VTE recurrence included indwelling venous catheters (40.0%), cancer (33.3%), subtherapeutic anticoagulation (26.7%), and nonadherence (23.3%). Recurrent VTE management strategies included switching anticoagulants (26.7%), increasing anticoagulant dose (20.0%), temporarily adding enoxaparin or unfractionated heparin to oral anticoagulation therapy (13.3%), or no change in anticoagulation therapy (43.3%). Only four adverse 90-day outcomes occurred among 17 patients who received anticoagulant therapy changes in response to VTE recurrence, whereas eight adverse outcomes occurred in the 13 patients who received no change in anticoagulation therapy in response to a recurrent VTE episode (P value 0.04). Regardless of the potential etiology of recurrent VTE during anticoagulant therapy; switching anticoagulants, temporarily adding injectable anticoagulants, or increasing anticoagulant intensity appears preferable to continuing current anticoagulant therapy unchanged.

The role of clinical pharmacy anticoagulation services in direct oral anticoagulant monitoring.

The role of dedicated anticoagulation management services (AMS) for patients receiving direct oral anticoagulant (DOAC) therapy is unclear. The objective of our study was to describe DOAC management in patients who were and were not managed by an AMS. We conducted a retrospective cohort study among patients with atrial fibrillation at the University of Utah Health (UUH) who received DOAC therapy between January 2013 and June 2016. Patients in the AMS group were managed by a pharmacist-led AMS whereas those in the non-AMS group were managed by other providers. The number and type of provider encounters and interventions related to DOAC therapy and a composite endpoint of thromboembolism, bleeding, and all-cause mortality were recorded. Overall, 90 and 370 patients were managed in the AMS and non-AMS groups, respectively. AMS group patients had greater chronic disease burden as measured by the Charlson comorbidity index. AMS group patients had more frequent DOAC-related encounters than non-AMS group patients but both groups had similar DOAC therapy intervention rates. Over half of patients in the AMS group received potentially duplicative interventions from their regular clinicians. The composite endpoint occurred in 18.9% and 13.5% of AMS and non-AMS group patients, respectively (p = 0.29). Patients managed by AMS providers were more complex and had more frequent encounters regarding their DOAC therapy than those managed by non-AMS providers. However, there was evidence of duplicative DOAC therapy management efforts. No difference between AMS and non-AMS groups in the composite clinical endpoint was detected.

Direct oral anticoagulant plus antiplatelet therapy: prescribing practices and bleeding outcomes.

Concurrent antiplatelet therapy (APT) is common during warfarin therapy but is less well-documented during direct oral anticoagulant (DOAC) therapy. Combined anticoagulant and APT use has been associated with increased bleeding risk without providing additional protection against thrombosis. This study aimed to describe single-center prescribing rates of DOAC + APT as well as compare bleeding rates between DOAC monotherapy and DOAC + APT cohorts. Patients receiving DOAC therapy were evaluated for APT use at the time of hospital discharge. Patients were categorized into DOAC monotherapy and DOAC + APT cohorts. Primary outcomes included DOAC + APT prescribing rate as well as rates of major bleeding and clinically relevant non-major bleeding (CRNMB) within six months after hospital discharge. Secondary outcomes included rates of thromboembolism and all-cause mortality. Of 407 patients receiving DOAC therapy, 78 (19.2%) also received APT at hospital discharge. Common indications for APT included secondary cardiovascular event prevention (57.7%) and primary cardiovascular event prevention (29.5%). The indication for APT could not be determined in 12.8% of patients. The major bleeding rate was 1.3% for DOAC + APT and 1.2% for DOAC monotherapy (p = 0.95). The CRNMB rate was 10.2% for DOAC + APT and 6.4% for DOAC monotherapy (p = 0.23). Thromboembolism and mortality were infrequent in both cohorts. DOAC + APT was documented in approximately 1 of 5 patients. Adding APT to DOAC therapy did not significantly increase the major bleeding or CRNMB rates compared to DOAC monotherapy but the sample size limits drawing conclusions about the safety of these regimens. Targeting primary prevention or unclear indications for APT could be a focus of future interventions.

Direct comparative effectiveness and safety between non-vitamin K antagonist oral anticoagulants for stroke prevention in nonvalvular atrial fibrillation: a systematic review and meta-analysis of observational studies.

The non-vitamin K antagonist oral anticoagulants (NOACs) have been increasingly prescribed in clinical practice for stroke prevention in patients with nonvalvular atrial fibrillation (AF). Direct comparisons between NOACs in trials are lacking, leaving an important clinical decision-making gap. We aimed to perform a systematic review and meta-analysis to summarize the evidence of observational studies for direct comparative effectiveness and safety amongst NOACs in patients with AF. Conference proceedings and electronic databases including MEDLINE, CINAHL, EMBASE and PUBMED were systematically searched. We included observational studies directly comparing individual NOACs in patients with nonvalvular AF who were aged ≥ 18 years for stroke prevention. Primary outcome included effectiveness outcome (stroke or systemic embolism) and safety outcome (major bleeding). Data were extracted in duplicated by two reviewers independently. A random-effects meta-analysis was conducted to synthesize the data from included observational studies. We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) to rate the overall quality of evidence for each outcome. Fifteen studies were included for qualitative synthesis, twelve studies for meta-analyses. It was found that rivaroxaban and dabigatran were similar with regard to risk of stroke or systemic embolism (Hazard ratio [HR] = 1.00, 95% CI 0.91-1.10; evidence quality: low), but rivaroxaban was associated with higher risk of major bleeding (HR = 1.39, 95% CI 1.28-1.50; evidence quality: moderate). Compared with apixaban, a significantly higher risk of major bleeding was observed with rivaroxaban (HR = 1.71, 95% CI 1.51-1.94; evidence quality: low). Apixaban was associated with lower risk of major bleeding, in comparison with dabigatran (HR = 0.80, 95% CI 0.68-0.95; evidence quality: low). No differences in risk of stroke or systemic embolism was observed between rivaroxaban versus apixaban, and apixaban versus dabigatran. In this study, apixaban was found to have the most favorable safety profile amongst the three NOACs. No significant difference was observed in risk of stroke or systemic embolism between the NOACs. Such findings may provide some decision-making support for physicians regarding their choices amongst NOACs in patients with AF.Registration PROSPERO (identifier: CRD42016052908).

Description of anti-Xa monitoring practices during low molecular weight heparin use.

Certain patient populations (pregnancy, cancer, renal impairment, and obesity) may be at higher risk of adverse events during low molecular weight heparin (LMWH) therapy and may benefit from anti-Xa monitoring. Yet, evidence supporting a standardized approach to anti-Xa monitoring correlated to clinical outcomes is lacking. Patients with at least one documented anti-Xa level and receiving LMWH within a 6-month period were identified. In a 6-month period, 224 adult LMWH patients with 359 anti-Xa levels were identified. Anti-Xa monitoring was most commonly performed in patients with active cancer receiving venous thromboembolism (VTE) treatment doses (57.4%) or obese patients receiving VTE prophylaxis (48.1%). Anti-Xa monitoring during renal impairment and pregnancy were infrequent (0.9% and 1.8%, respectively). Most (71.9%) anti-Xa levels were therapeutic, but only 45% were drawn correctly in relation to LMWH administration time. Compared to those with therapeutic anti-Xa levels, patients with out-of-range levels were four times as likely to receive a LMWH therapy change (odds ratio, 4.16; 95% confidence interval, 2.53-6.84). However, when levels were supratherapeutic or subtherapeutic, the LMWH doses remained unchanged in one-third to one-half of patients, respectively. Anti-Xa monitoring was most commonly performed in patients with cancer or obesity and was more common with VTE prophylaxis dosing. The majority of levels were therapeutic, indicating that anti-Xa monitoring may be unnecessary even in high-risk patient populations. Many out-of-range anti-Xa levels did not prompt a change in LMWH therapy. Further research is still needed to determine if anti-Xa- guided LMWH dosing improves clinical outcomes.

Assessing patient preferences for switching from warfarin to direct oral anticoagulants.

Warfarin remains the most commonly prescribed oral anticoagulant in the United States, but it has disadvantages such as dietary interactions and frequent laboratory monitoring. Direct oral anticoagulants (DOACs) have been introduced as safer and equally effective alternatives to warfarin. This study assessed patient preference for warfarin or DOAC based on a willingness to pay more for potential DOAC benefits. Current warfarin patients with atrial fibrillation or venous thromboembolism enrolled in the University of Utah Health Thrombosis Service were given a one-time electronic survey that assessed preferences between warfarin and DOACs using scenarios comparing effectiveness, safety, and convenience. When DOACs were preferred, patients were asked how much more they would be willing to pay monthly for the perceived advantages associated with DOACs. With 123 completed surveys, 68% of patients preferred to stay on warfarin. No particular factor influenced patient preference (lack of routine laboratory monitoring, lower risks of major bleeding, and fewer dietary interactions). Reduced stroke risk was associated with the highest value (willing to pay an additional $21). Considering all factors, patients preferring DOACs would pay a median $18 extra per month for the additional benefits. Prior exposure to DOACs was associated with preference for DOACs. Many patients currently taking warfarin preferred to stay on warfarin when given the choice, despite DOAC benefits. Willingness to pay extra for DOAC advantages did not exceed $20 in the majority of survey respondents. Previous DOAC exposure influences patient preference and perceived value for DOACs.

Understanding patients' care barriers in the treatment of venous thromboembolism.

Venous thromboembolism (VTE) is a major health care problem. There are common barriers to quality healthcare but are these barriers the same for VTE patients? A national online survey was administered to adults who had experienced a recent VTE event. The survey assessed perceptions of VTE care barriers: (1) Difficulty to meet healthcare costs related to VTE care; (2) difficulty to meet costs for VTE prescription medications; (3) difficulty with transportation to get VTE care; and (4) the degree of support of others needed to get VTE care. Each question was correlated with patient demographics including income level, place of residence, current work status, and health insurance; care related patient harms experienced with the VTE episode; number of lifetime VTE events; beliefs concerning VTE outcomes, and oral anticoagulant therapy type. Logistic regression analysis was used to determine the effect of independent variables on barriers to VTE care. Approximately 30% of VTE patients reported at least one significant barrier to VTE care. Patients rated healthcare costs and VTE prescription medication costs mildly difficult. The odds of reporting barriers were positively associated with the number of DVTs experienced in the previous 2 years. VTE-related depression was also moderately associated with increased odds of reporting significant VTE care barriers. Nearly 1 in 3 VTE sufferers reported significant barriers to VTE care, with healthcare costs and VTE medication costs being the most common. Efforts to identify patients who may experience barriers should be sought early in care.

Assessing the accuracy of ICD-10 codes for identifying acute thromboembolic events among patients receiving anticoagulation therapy.

International classification of disease (ICD) codes can improve the efficiency of epidemiological research provided the codes accurately identify outcomes of interest. The purpose of this retrospective cross-sectional study is to evaluate the accuracy of ICD-10 codes for identifying thromboembolic events occurring during anticoagulation therapy. Medical charts of patients hospitalized for any reason while receiving anticoagulant therapy between September 1, 2017 and December 31, 2017 were reviewed by two reviewers blinded to ICD-10 code status. Following identification of confirmed acute thromboembolic events, ICD-10 codes were unblinded and sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) along with 95% confidence intervals (CI) were calculated for coding in any diagnosis position ("principal" or "other"). There were 661 hospitalizations identified among 487 anticoagulated patients. There were 27 thromboembolic events identified during chart review. Stroke and venous thromboembolism were the most common thromboembolic event types. Overall thromboembolic ICD-10 coding sensitivity was 100.0% (95% CI 87.2-100.0); specificity was 79.3% (75.9-82.4). PPV was 17.1% (11.6-23.9%), and NPV was 100% (99.3-100.0). ICD-10 codes can reliably be used for ruling out hospitalizations for thromboembolic events in patients receiving anticoagulation therapy but should not be used for identifying thromboembolic complications without confirmatory chart review.

Real-world assessment of off-label direct oral anticoagulant dosing for venous thromboembolism.

Preferred anticoagulation therapy for venous thromboembolism (VTE) has shifted from warfarin to direct oral anticoagulants (DOACs). Adherence to DOAC prescribing information is an important quality measure as off-label doses have been associated with increased risk of adverse events (AEs). To identify the prevalence, outcomes, and patient characteristics associated with off-label DOAC dosing during VTE treatment. Patients receiving DOAC for VTE treatment discharged from University of Utah Health (UUH) over a 90-day period were identified. Dosing was classified as "labeled" or "off-label" based on concordance with manufacturer prescribing information. AEs (thromboembolic events, bleeding, death) occurring within 90 days after discharge were identified. Out of 195 patients, 154 (79.0%) received labeled dosing, 31 (15.9%) received off-label dosing, and 10 (5.1%) were indeterminate. Two-thirds of off-label doses were higher than recommended and three-fourths occurred during extended treatment (more than 90 days post-VTE). Off-label dosing rates dropped to 5.6% when 6-month dose reductions were not required. Off-label dosing was associated with apixaban use and extended phase treatment (p < 0.001). No association was found between off-label dosing and age, renal function, prescriber rationale for dose selection, or Thrombosis Clinic referral. AEs were experienced by 18 (11.7%) and 3 (9.7%) patients in the labeled and off-label groups, respectively (p = 0.77). Bleeding events comprised 46.2% of AEs. The rate of off-label DOAC dosing for VTE at UUH was within rates reported in prior studies, occurred primarily with extended-duration apixaban, and did not result in a higher rate of AEs.

Laboratory Monitoring of Low-Molecular-Weight Heparin and Fondaparinux.

Compared with older agents, low-molecular-weight heparins (LMWH) and fondaparinux offer improved bioavailability and more predictable, dose-independent clearance. While routine monitoring of coagulation parameters is not usually necessary with these agents, certain populations (including pregnant patients, children, obese patients, and patients with renal impairment) may benefit from the monitoring of anti-factor Xa activity, thromboelastography, or other coagulation assays to help guide therapy. The chromogenic anti-factor Xa assay is currently the gold standard for monitoring LMWH and fondaparinux therapy. Thromboelastography has been used to monitor LMWH therapy in special situations but is not needed for routine use.

Validity of Using Inpatient and Outpatient Administrative Codes to Identify Acute Venous Thromboembolism: The CVRN VTE Study.

BACKGROUND: Administrative data are frequently used to identify venous thromboembolism (VTE) for research and quality reporting. However, the validity of these codes, particularly in outpatients, has not been well-established. OBJECTIVE: To determine how well International Classification of Diseases, Ninth Revision (ICD-9) codes for VTE predict chart-confirmed acute VTE in inpatient and outpatients. PATIENTS AND METHODS: We selected 4642 adults with an incident ICD-9 diagnosis of VTE between years 2004 and 2010 from the Cardiovascular Research Network Venous Thromboembolism cohort study. Medical charts were reviewed to determine validity of events. Positive predictive values (PPVs) of ICD-9 codes were calculated as the number of chart-validated VTE events divided by the number with specific VTE codes. Analyses were stratified by VTE type [pulmonary embolism (PE), deep venous thrombosis (DVT)], code position (primary, secondary), and setting [hospital/emergency department (ED), outpatient]. RESULTS: The PPV for any diagnosis of VTE was 64.6% for hospital/ED patients and 30.9% for outpatients. Primary diagnosis codes from hospital/ED patients were more likely to represent acute VTE than secondary diagnosis codes (78.9% vs. 44.4%, P<0.001). Primary hospital/ED codes for PE and lower extremity DVT had higher PPV than for upper extremity DVT (89.1%, 74.9%, and 58.1%, respectively). Outpatient codes were poorly predictive of acute VTE: 28.0% for PE and 53.6% for lower extremity DVT. CONCLUSIONS: ICD-9 codes for VTE obtained from outpatient encounters or from secondary diagnosis codes do not reliably reflect acute VTE. More accurate ways of identifying VTE in outpatients are needed before these codes can be adopted for research or policy purposes.