Delivery of Optimized Anticoagulant Therapy: Consensus Statement from the Anticoagulation Forum

Quality of warfarin management following transfer from an anticoagulation clinic to primary care

BACKGROUND

Advances in alternative oral anticoagulants has reduced use and clinician comfort with warfarin. Our specialty anticoagulation clinic (AC) operates at maximum capacity and must transfer patients to accept new referrals.

OBJECTIVES

To compare time within therapeutic range (TTR) during 6 months of AC care versus following transfer to primary care for a minimum of 6 months and to a maximum of 24 months. Secondarily, to compare frequency of INR assessments, proportion of INRs ≤1.5 and > 5, and rates of bleeding and thromboembolic events post-transfer to primary care.

METHODS

Mixed retrospective chart review and administrative audit with a before-after study design for patients managed by the University of Alberta's AC for at least 6 months that were transferred to primary care.

RESULTS

177 (27.7 %) patients were included, managed by the AC for 3.4 years (1.3, 7.9). TTR declined during the first 6 months post-transfer with AC care achieving 69.2 % and primary care 64.5 % (p = 0.02) and when compared to the 24-month interval (69.2 % vs 63.4 %; respectively; p = 0.003). A shorter interval between INRs in AC care was observed (28.9 (24.4) vs 34.5 (31.7) days, respectively; p = 0.0004). Similar numbers of critical INRs occurred between groups, whereas more INRs ≤1.5 occurred in primary care (7.3 % vs 4.7 %, respectively; p = 0.0003). Bleeding and thromboembolic event rates were balanced following transfer to primary care with both occurring at 9.4 % per patient year.

CONCLUSION

A decline in anticoagulation control after transfer to primary care was observed, which appeared to be driven by a greater proportion of subtherapeutic INRs.

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.

Virtual Education for Patient Self-Testing for Warfarin Therapy Is Effective During the COVID-19 Pandemic

BACKGROUND

Prior to the COVID-19 pandemic, warfarin users were required to complete in-person training in order to participate in approved international normalized ratio (INR) patient self-testing (PST) programs. To minimize in-person contact during the pandemic, a federal waiver of the in-person training requirement allowed new patients to begin PST after completing virtual training. However, it was uncertain whether such patients achieved comparable levels of INR control to patients receiving in-person training.

METHODS

INR results for patients receiving virtual training upon PST commencement between April 1, 2020, and December 31, 2020, were compared to those of patients initiating PST with in-person training between April 1, 2019, and December 31, 2019. The primary outcome was the difference in warfarin time in therapeutic range (TTR) between the groups, with secondary outcomes including differences in the percentages of INR values within individually prescribed INR range and of critical INR values.

RESULTS

The records of 33,683 patients were included in the analysis (13,568 in the "In-Person" sample; 20,115 in the "Virtual" sample). Patients in the Virtual sample achieved a TTR of 66.78%, compared to the In-Person sample (64.19%; absolute difference 2.59; 95% confidence interval [CI] = 2.50-2.68, p < 0.001). The TTR values were also statistically significantly higher in all subgroups evaluated across categories of patient age, gender, geography, and indication. Similarly favorable results were achieved for INR values in range and critical values.

CONCLUSION

Virtual education for PST for warfarin therapy is effective and should continue to be an option for patients and providers throughout the pandemic, and possibly beyond.

Pharmacist monitoring of direct oral anticoagulants for American Indians and Alaska Natives in the outpatient setting

BACKGROUND

Direct oral anticoagulants (DOACs) call into question the role of traditional pharmacist-run clinics, and few studies have described the incorporation of DOAC's into traditional anticoagulation management services (AMS) OBJECTIVE: To describe the incorporation of DOACs into a pharmacist-run AMS for American Indian and Alaska Native (AI/AN) patients and determine outcomes related to adherence, follow-up, and pharmacist interventions.

PRACTICE DESCRIPTION

Traditional AMS embedded in ambulatory clinic. Warfarin managed by pharmacists under a collaborative practice agreement with supervising physician.

PRACTICE INNOVATION

DOACs incorporated into AMS by transitioning warfarin patients to rivaroxaban and apixaban and managing new patients with DOAC. Follow-up occurred via phone call and at longer intervals.

EVALUATION METHODS

Single-center, retrospective, observational analysis of AI/AN patients who were followed up by pharmacy AMS. The outcomes measured include adherence to DOAC therapy, number of telephonic encounters versus face-to-face visits, frequency of follow-up, types of interventions made at each visit, and an estimate of face-to-face clinic time savings.

RESULTS

A total of 50 patients were included for analysis. The average medication possession ratio was 91%. The majority of visits occurred over the phone (59%), and most follow-up visits occurred every 3 months (62%). The top 3 most frequent interventions were adherence education, initial DOAC education, and education on use of nonsteroidal anti-inflammatory drugs.

PRACTICE IMPLICATIONS

Traditional AMS can evolve by incorporating DOACs and maintaining follow-up.

CONCLUSION

Pharmacist monitoring of DOACs may promote high levels of adherence and lead to time savings by reducing the amount of time spent in traditional AMS.

Uptake and Utilization of the Management of Anticoagulation in the Periprocedural Period App: Longitudinal Analysis

Background

Anticoagulants are major contributors to preventable adverse drug events, and their optimal management in the periprocedural period is particularly challenging. Traditional methods of disseminating clinical guidelines and tools cannot keep pace with the rapid expansion of available therapeutic agents, approved indications for use, and published medical evidence, so a mobile app, Management of Anticoagulation in the Periprocedural Period (MAPPP), was developed and disseminated to provide clinicians with guidance that reflects the most current medical evidence.

Objective

The objective of this study was to assess the global, national, and state-level acquisition of a mobile app since its initial release and characterize individual episodes of use based on drug selection, procedural bleeding risk, and patient thromboembolic risk.

Methods

Data were extracted from a mobile app usage tracker (Google Analytics) to characterize new users and completed episodes temporally (by calendar quarter) and geographically (globally, nationally, and in the targeted US state of New York) for the period between April 1, 2016 and September 30, 2017.

Results

The app was acquired by 2866 new users in the measurement period, and the users completed nearly 10,000 individual episodes of use. Acquisition and utilization spanned 51 countries globally, predominantly in the United States and particularly in New York State. Warfarin and rivaroxaban were the most frequently selected drugs, and completed episodes most frequently included the selection of high bleeding risk (4888/9963, 49.06%) and high thromboembolic risk categories (4500/9963, 45.17%).

Conclusions

The MAPPP app is a successful means of disseminating current guidance on periprocedural anticoagulant use, as indicated by broad global uptake and upward trends in utilization. Limitations in access to provider and patient-specific data preclude objective evaluation of the clinical impact of the app. An ongoing study incorporating app logic into electronic health record systems at participant health systems will provide a more definitive evaluation of the clinical impact of the app logic.

Role of the anticoagulant monitoring service in 2018: beyond warfarin

The direct oral anticoagulants (DOACs) have a wide therapeutic index, few drug interaction, no dietary interactions and do not require dose adjustment according to the results of routine coagulation testing. Despite these advantages over warfarin, the DOACs remain high risk medications. There is evidence that non-adherence, off-label dosing and inadequate care transitions during DOAC therapy increase the risk of bleeding and thromboembolic complications. Although DOACs are approved for a growing number of indications, there remain patient populations who are not good candidates. Existing expertise within an Anticoagulation Management Service (AMS) should be leveraged to optimize all anticoagulant therapies including the DOACs. The AMS can facilitate initial drug therapy selection and dose management, reinforce patient education and adherence as well as managing drug interactions and invasive procedures. In the event that a transition to warfarin is warranted, the AMS is already engaged which limits the risk of fragmented patient care and ensures that therapeutic anticoagulation is re-established in a timely manner. The AMS of the future will provide comprehensive management for all patients receiving anticoagulant medications and continue to provide anticoagulation expertise to the healthcare team.

Defining Minimum Necessary Anticoagulation-Related Communication at Discharge: Consensus of the Care Transitions Task Force of the New York State Anticoagulation Coalition

BACKGROUND

Anticoagulated patients are particularly vulnerable to ADEs when they experience changes in medical acuity, pharmacotherapy, or care setting, and resources guiding care transitions are lacking. The New York State Anticoagulation Coalition convened a task force to develop a consensus list of requisite data elements (RDEs) that should accompany all anticoagulated patients undergoing care transitions.

METHODS

A multidisciplinary panel of 15 anticoagulation experts voluntarily completed an iterative Delphi process. Resources were disseminated and deliberated via remote technology, with consensus achieved via blinded electronic polling.

RESULTS

The panel reached consensus on a list of 15 RDEs for anticoagulation communication at discharge (the ACDC List). Consensus was rapidly achieved by the full panel on 13 elements, while 3 (2 of which were combined into 1 element) required multiple iterations and achieved consensus with votes from 8 available panelists. The elements encompassed a range of factors, including drug use and indications, previous exposure and duration of therapy, recent drug exposure and laboratory results and expectations for subsequent administration, therapy goals, patient education and comprehension, and expectations for clinical management. Twelve of the elements are applicable to any anticoagulant, and 3 are specific to warfarin.

CONCLUSION

The ACDC List identifies specific pieces of clinical information that a panel of anticoagulant experts agree should be communicated to downstream providers for all anticoagulated patients undergoing care transitions. Additional study is needed to objectively evaluate the ability of existing care systems to communicate the elements and to assess possible relationships between communication of the elements and clinical outcomes.

Out-of-range INR results lead to increased health-care utilization in four large anticoagulation clinics

BACKGROUND

The impact on health-care costs and utilization of a single out-of-range (OOR) INR value not associated with bleeding or thromboembolic complication among chronic warfarin-treated patients is not well described.

METHODS

At four large phone-based anticoagulation clinics (total 14 948 patients), warfarin-treated patients with atrial fibrillation (AF) or venous thromboembolism were retrospectively propensity matched into an OOR INR group (n = 116) and a control group (n = 58). Types and frequency of contacts (eg, phone, voicemail, facsimile) and personnel involved were identified. A prospective time study analysis of 59 OOR and 92 control patients was performed over 8.5 days to record the time required to care for these patients. 2016 USD cost estimates were generated from average salaries.

RESULTS

OOR and in-range INR patients experienced an average of 4.2 and 3.2 (P < .001) INR lab draws until two sequential tests were in range. OOR INR patients required an average of 5.3 interactions with the anticoagulation clinic vs 3.7 for in-range INR patients (P < .001). OOR INR patients more often required phone calls, fewer mailed letters, and more often required multiple types of contact than in-range INR patients. In the prospective analysis, total median time involved for each OOR INR value was 5.1 minutes (IQR 3.7-9.5) vs 2.9 minutes (IQR 1.8-5.8) for control INR values (P < .001). At the clinic level, OOR INR values were associated with a yearly staff cost of $17 938 (IQR $8969-$31 391).

CONCLUSIONS

We quantified the amount of extra anticoagulation staff effort required to manage warfarin-treated patients who experience a single OOR INR value without bleeding or thromboembolic complications, which leads to higher healthcare utilization costs.

Continuation of Aspirin Therapy before Cataract Surgery with Different Incisions: Safe or Not?

Purpose

To assess whether to continue aspirin therapy while having uncomplicated phacoemulsification cataract surgery with different incisions.

Methods

Consecutive patients having cataract surgery under topical anesthesia with different incisions between May 2016 and August 2017 were followed. 236 eyes of 166 patients on routine aspirin therapy were randomized into 2 groups: continuation group, 112 eyes; discontinuation group, 124 eyes. 121 eyes of 94 patients on no routine anticoagulant therapy were used as the control group. Patients were examined 1 day preoperatively and 1 day and 7 days postoperatively. Intraoperative and postoperative complications were recorded.

Results

Statistically, there was no significant difference about postoperative BCVA among three groups. A higher incidence of subconjunctival hemorrhage was shown in the continuation group than in the discontinuation group and the control group (17.0% versus 8.1%, p=0.038; 17.0% versus 7.4%, p=0.025, resp.). Although corneal edema was greater in clear corneal incision cases than that of scleral tunnel incision cases (22.5% versus 12.0%, p=0.009), subconjunctival hemorrhage was greater in scleral tunnel incision cases (14.9% versus 6.6%, p=0.011). Subgroup analyses revealed that patients of scleral tunnel incision who continued taking aspirin had a higher incidence of subconjunctival hemorrhage compared with those who discontinued (25.5% versus 10.9%, p=0.038), but no same conclusion in clear corneal incision cases (8.8% versus 5.0%, p=0.483).

Conclusions

The outcomes indicated that phacoemulsification cataract surgery under topical anesthesia could be safely performed without ceasing systemic aspirin therapy. Clear corneal incision could be a better choice in patients treated with aspirin.

Patient Education on Oral Anticoagulation

Given the potential harm associated with anticoagulant use, patient education is often provided as a standard of care and emphasized across healthcare settings. Effective anticoagulation education involves face-to-face interaction with a trained professional who ensures that the patient understands the risks involved, the precautions that should be taken, and the need for regular monitoring. The teaching should be tailored to each patient, accompanied with written resources and utilize the teach-back method. It can be incorporated in a variety of pharmacy practice settings, including in ambulatory care clinics, hospitals, and community pharmacies.

Development of Quality Indicators to Assess Oral Anticoagulant Management in Community Pharmacies for Patients with Atrial Fibrillation

BACKGROUND

Few studies have evaluated the quality of oral anticoagulant management by community pharmacists. There is no complete set of quality indicators available for this purpose.

OBJECTIVE

To develop a set of specific quality indicators to assess oral anticoagulant management by community pharmacists for patients with atrial fibrillation (AF).

METHODS

Quality indicators were developed in 3 phases. In phase 1, potential quality indicators were generated based on clinical guidelines and a literature review. In phase 2, a modified RAND appropriateness method involving 2 rounds was implemented with 9 experts, who judged the appropriateness of quality indicators generated in phase 1 based on the extent to which they were accurate, based on evidence, relevant, representative of best practices, and measurable in community pharmacies. Phase 3 consisted of a feasibility assessment in 5 community pharmacies on 2 patients each.

RESULTS

The final set included 38 quality indicators grouped into 6 categories: documentation (n = 29), risk assessment (n = 3), clinical control (n = 1), clinical follow-up (n = 15), choice of therapy (n = 11), and interaction management (n = 8). The quality indicators referred to process of care (n = 34), clinical outcomes (n = 2), or structure of care (n = 2). There were 24 quality indicators related to vitamin K antagonists (VKAs), and 17 were related to direct oral anticoagulants (DOACs). To assess quality indicators, a questionnaire was developed for completion by community pharmacists for each patient, which included 17 questions about VKA patients and 12 questions about DOAC patients.

CONCLUSIONS

A first set of quality indicators is now available to assess the quality of oral anticoagulant management by community pharmacists for patients with AF.

DISCLOSURES

This research was supported by the Réseau Québécois de recherche sur le médicament (RQRM); the Blueprint for Pharmacy in collaboration with Pfizer Canada; and the Cercle du Doyen of the Faculty of Pharmacy, University of Montreal. The study sponsors were not involved in the study design, data collection, data interpretation, the writing of the article, or the decision to submit the report for publication. Chartrand received a scholarship from the Fonds de Recherche du Québec en Santé (FRQ-S), the Réseau Québécois de recherche sur l'usage des médicaments with Pfizer, and the Faculty of Pharmacy, University of Montreal. Guénette holds a Junior-1 Clinician Researcher Award from the FRQ-S in partnership with the Société québécoise d'hypertension artérielle. Williamson holds a Junior-1 Career Award from the FRQ-S. Côté reported being a medical speaker for Bayer, Boehringer Ingelheim Canada, and Pfizer Canada. The other authors reported no conflicts of interest. Study concept and design were contributed by Lalonde, Chartrand, and Martin. Chartrand, Martin, and Lalonde collected the data, along with Brouillette, Côté, Huot, Landry, Martineau, Perreault, Williamson, and White-Guay. Data interpretation was performed by Chartrand, Gagnon, and Lalonde, along with Guénette and Martin. The manuscript was primarily written by Chartrand, along with Guénette and Lalonde, and revised by Chartrand, Guénette, and Lalonde, along with the other authors. A portion of this study's results was presented at the 4th RQRM Annual Meeting on September 22-23, 2014, in Orford, Quebec, Canada, in the form of an abstract, which was published in the Journal of Population Therapeutics and Clinical Pharmacology, 2014;21(2):e312.

Advances in the Therapy of Bleeding Peptic Ulcer

Peptic ulcer bleeding remains an important medical emergency. Important recent advances are reviewed. These include further support for a more restrictive transfusion strategy aiming for a target haemoglobin of 70-90 g/L. The Glasgow-Blatchford score remains the most useful assessment score for identifying the lowest risk patients suitable for outpatient management and predicting the need for intervention. Newer scores such as the AIMS65 and Progetto Nazionale Emorragia Digestive score (PNED) may be more accurate in predicting mortality. Pre-endoscopy erythromycin improves outcomes and is underused. A new disposable Doppler probe appears to provide more accurate determination of both rebleeding risk and the success of endoscopic therapy than purely visual guidance. Over-the-scope clips and haemostatic powders appear to have some role as endoscopic salvage therapies. Non- H. pylori, non-aspirin/non-steroidal anti-inflammatory drug (NSAID) ulcers contribute to an increasing percentage of bleeding peptic ulcers and are associated with a high rebleeding rate. The optimal management of these ulcers remains to be determined.

Recent advances in the management of peptic ulcer bleeding

Acute upper gastrointestinal haemorrhage due to peptic ulcer bleeding remains an important cause of emergency presentation and hospital admission. Despite advances in many aspects of management, peptic ulcer bleeding is still associated with significant morbidity, mortality, and healthcare costs. Comprehensive international guidelines have been published, but advances as well as controversies continue to evolve. Important recent advances include the evidence supporting a more restrictive transfusion strategy aiming for a target haemoglobin of 70-90 g/l. Comparative studies have confirmed that the Glasgow-Blatchford score remains the most useful score for predicting the need for intervention as well as for identifying the lowest-risk patients suitable for outpatient management. New scores, including the AIMS65 and Progetto Nazionale Emorragia Digestiva score, may be more accurate in predicting mortality. Pre-endoscopy erythromycin appears to improve outcomes and is probably underused. High-dose oral proton pump inhibition (PPI) for 11 days after PPI infusion is advantageous in those with a Rockall score of 6 or more. Oral is as effective as parenteral iron at restoring haemoglobin levels after a peptic ulcer bleed and both are superior to placebo in this respect. Within endoscopic techniques, haemostatic powders and over-the-scope clips can be used when other methods have failed. A disposable Doppler probe appears to provide more accurate determination of both rebleeding risk and the success of endoscopic therapy than purely visual guidance. Non- Helicobacter pylori, non-aspirin/non-steroidal anti-inflammatory drug ulcers contribute an increasing percentage of bleeding peptic ulcers and are associated with a poor prognosis and high rebleeding rate. The optimal management of these ulcers remains to be determined.

The genetic basis of antiplatelet and anticoagulant therapy: A pharmacogenetic review of newer antiplatelets (clopidogrel, prasugrel and ticagrelor) and anticoagulants (dabigatran, rivaroxaban, apixaban and edoxaban)

INTRODUCTION

The study of pharmacogenomics presents the possibility of individualised optimisation of drug therapy tailored to each patients' unique physiological traits. Both antiplatelet and anticoagulant drugs play a key role in the management of cardiovascular disease. Despite their importance, there is a substantial volume of literature to suggest marked person-to-person variability in their effect. Areas covered: This article reviews the data available for the genetic cause for this inter-patient variability of antiplatelet and anticoagulant drugs. The genetic basis for traditional antiplatelets (i.e. aspirin) is compared with the newly available antiplatelet medicines (clopidogrel, prasugrel and ticagrelor). Similarly, the pharmacogenetics of warfarin is compared with the newer direct oral anticoagulants (DOACs) in detail. Expert Opinion: We identify strengths and weaknesses in the research thus far; including shortcomings in trial design and a review of newer analytical techniques. The direction of this research and its real-world implications are discussed.

Association of Proton Pump Inhibitors With Reduced Risk of Warfarin-Related Serious Upper Gastrointestinal Bleeding

BACKGROUND & AIMS

Proton pump inhibitors (PPIs) might reduce the risk of serious warfarin-related upper gastrointestinal bleeding, but the evidence of their efficacy for this indication is limited. A gastroprotective effect of PPIs would be particularly important for patients who take warfarin with antiplatelet drugs or nonselective nonsteroidal anti-inflammatory drugs (NSAIDs), which further increase the risk of gastrointestinal bleeding.

METHODS

This retrospective cohort study of patients beginning warfarin treatment in Tennessee Medicaid and the 5% National Medicare Sample identified 97,430 new episodes of warfarin treatment with 75,720 person-years of follow-up. The study end points were hospitalizations for upper gastrointestinal bleeding potentially preventable by PPIs and for bleeding at other sites.

RESULTS

Patients who took warfarin without PPI co-therapy had 119 hospitalizations for upper gastrointestinal bleeding per 10,000 person-years of treatment. The risk decreased by 24% among patients who received PPI co-therapy (adjusted hazard ratio [HR], 0.76; 95% confidence interval [CI], 0.63-0.91). There was no significant reduction in the risk of other gastrointestinal bleeding hospitalizations (HR, 1.07; 95% CI, 0.94-1.22) or non-gastrointestinal bleeding hospitalizations (HR, 0.98; 95% CI, 0.84-1.15) in this group. Among patients concurrently using antiplatelet drugs or NSAIDs, those without PPI co-therapy had 284 upper gastrointestinal bleeding hospitalizations per 10,000 person-years of warfarin treatment. The risk decreased by 45% (HR, 0.55; 95% CI, 0.39-0.77) with PPI co-therapy. PPI co-therapy had no significant protective effect for warfarin patients not using antiplatelet drugs or NSAIDs (HR, 0.86; 95% CI, 0.70-1.06). Findings were similar in both study populations.

CONCLUSIONS

In an analysis of patients beginning warfarin treatment in Tennessee Medicaid and the 5% National Medicare Sample, PPI co-therapy was associated with reduced risk of warfarin-related upper gastrointestinal bleeding; the greatest reduction occurred in patients also taking antiplatelet drugs or NSAIDs.

Guidance for the practical management of warfarin therapy in the treatment of venous thromboembolism

Venous thromboembolism (VTE) is a serious and often fatal medical condition with an increasing incidence. The treatment of VTE is undergoing tremendous changes with the introduction of the new direct oral anticoagulants and clinicians need to understand new treatment paradigms. This article, initiated by the Anticoagulation Forum, provides clinical guidance based on existing guidelines and consensus expert opinion where guidelines are lacking. Well-managed warfarin therapy remains an important anticoagulant option and it is hoped that anticoagulation providers will find the guidance contained in this article increases their ability to achieve optimal outcomes for their patients with VTE Pivotal practical questions pertaining to this topic were developed by consensus of the authors and were derived from evidence-based consensus statements whenever possible. The medical literature was reviewed and summarized using guidance statements that reflect the consensus opinion(s) of all authors and the endorsement of the Anticoagulation Forum’s Board of Directors. In an effort to provide practical and implementable information about VTE and its treatment, guidance statements pertaining to choosing good candidates for warfarin therapy, warfarin initiation, optimizing warfarin control, invasive procedure management, excessive anticoagulation, subtherapeutic anticoagulation, drug interactions, switching between anticoagulants, and care transitions are provided.

Integrating electronic health records in the delivery of optimized anticoagulation therapy

Integration of accepted practice standards into electronic health record systems can facilitate standardization of anticoagulation care delivery and result in improved anticoagulation safety. However, the majority of commonly used electronic health record systems are lacking the specialized features necessary for optimal anticoagulation management. The Task Force on Electronic Health Records of the New York State Anticoagulation Coalition provides such a Consensus Statement in this issue of the journal. The Anticoagulation Forum endorses these recommendations and advises the electronic health record industry and health information technology programmers at the institutional level to adopt these recommendations in a comprehensive and timely manner.

Patients' and physicians' satisfaction with a pharmacist managed anticoagulation program in a family medicine clinic

BACKGROUND

A pharmacist managed anticoagulation service was initiated in a multi-physician family medicine clinic in December 2006. In order to determine the patient and physician satisfaction with the service, a study was designed to describe the patients' satisfaction with the warfarin education and management they received from the pharmacist, and to describe the physicians' satisfaction with the level of care provided by the pharmacist for patients taking warfarin. A self-administered survey was completed by both eligible patients receiving warfarin and physicians prescribing warfarin between December 2006 and May 2008. The patient survey collected information on patient demographics, satisfaction with warfarin education and daily warfarin management. The physician survey collected data about the satisfaction with patient education and daily anticoagulation management by the pharmacist.

RESULTS

Seventy-six of 94 (81%) patients completed the survey. Fifty-nine percent were male with a mean age of 65 years (range 24-90). Ninety-six percent agreed/strongly agreed the pharmacist did a good job teaching the importance of warfarin adherence, the necessity of INR testing and the risks of bleeding. Eighty-five percent agreed/strongly agreed the risk of blood clots was well explained, 79% felt the pharmacist did a good job teaching about dietary considerations and 77% agreed/strongly agreed the pharmacist explained when to see a doctor. All patients felt the pharmacist gave clear instructions on warfarin dosing and INR testing. Four of nine physicians (44%) completed the survey. All agreed/strongly agreed the pharmacist was competent in the care provided, were confident in the care their patients received, would like the pharmacist to continue the service, and would recommend this program to other clinics.

CONCLUSIONS

Patients and family physicians were satisfied with the pharmacist managed anticoagulation program and recommended continuation of the program. These results support the role of the pharmacist in the management of anticoagulation in a multi-physician family medicine clinic.

Physician's fear of anticoagulant therapy in nonvalvular atrial fibrillation

Despite the availability of predictive tools and treatment guidelines, anticoagulant therapies are underprescribed and many patients are undertreated for conditions that predispose to thromboembolic complications, including stroke. This review explores reasons for which physicians fear that the risks of anticoagulation may be greater than the potential benefit. The results of numerous clinical trials confirm that patients benefit from judiciously managed anticoagulation and that physicians can take various approaches to minimize risk. Use of stratification scores for patient selection and accurate estimation of stroke risk may improve outcomes; bleeding risk is less important than stroke risk. Adoption of newer anticoagulants with simpler regimens may help physicians allay their fears of anticoagulant use in patients with atrial fibrillation. These fears, although not groundless, should not overtake caution and hinder the delivery of appropriate evidence-based care.

New insights into treatment of venous thromboembolism

Several advances have occurred over the last 2 years in the clinical management of venous thromboembolism (VTE), as evidenced by several high-profile publications in top-tier medical journals. The translation of the knowledge gained into routine clinical practice is an important challenge so that VTE is managed optimally and established and new anticoagulants are used effectively and safely. This chapter reviews issues of VTE treatment from acute management to treatment of long-term complications, addressing new data gained in the last 2 years and putting them into a clinical context, with the goal of improved everyday VTE management.

Guidelines for the primary prevention of stroke: a statement for healthcare professionals from the American Heart Association/American Stroke Association

The aim of this updated statement is to provide comprehensive and timely evidence-based recommendations on the prevention of stroke among individuals who have not previously experienced a stroke or transient ischemic attack. Evidence-based recommendations are included for the control of risk factors, interventional approaches to atherosclerotic disease of the cervicocephalic circulation, and antithrombotic treatments for preventing thrombotic and thromboembolic stroke. Further recommendations are provided for genetic and pharmacogenetic testing and for the prevention of stroke in a variety of other specific circumstances, including sickle cell disease and patent foramen ovale.

Features of electronic health records necessary for the delivery of optimized anticoagulant therapy: consensus of the EHR Task Force of the New York State Anticoagulation Coalition

BACKGROUND

Oral anticoagulants are prescribed to millions of Americans, and consequently are among the medications most likely to contribute to emergency department visits and hospitalizations. Although guidelines and consensus statements promote systematic approaches to therapy, anticoagulation (AC) management is often suboptimal. Electronic health records (EHRs) have the potential to improve safety and quality but have not yet incorporated specialized features necessary to optimize therapy.

OBJECTIVE

To generate a comprehensive, consensus-based list of EHR features clinically necessary to deliver optimized AC management, provide a "language bridge" to accelerate incorporation of features into EHR systems, and suggest mechanisms for the objective evaluation of available EHRs.

METHODS

A multidisciplinary panel of AC specialists utilized the framework of a previously published consensus statement to map outpatient AC management and developed a comprehensive array of sequential computer logic steps using a restricted language scheme. Logic steps were then translated into narrative descriptions of potential EHR features, which were refined through multiple group evaluations. A finalized list of proposed features was ranked according to perceived clinical necessity by physician, pharmacist, and nurse panelists in a blinded manner using a 5-point Likert scale. Features receiving no more than 1 dissenting opinion were included in a finalized list of clinically necessary features.

RESULTS

The task force generated 78 recommended EHR features across 20 key discrete areas and 425 individual logic steps. All recommended features received Strongly Agree or Agree rankings regarding their perceived clinical necessity, and no feature received more than a single Disagree response.

CONCLUSION

The incorporation of key AC-related features into existing EHRs or specialized AC management systems has the potential to systematize the delivery of optimal AC care by health care professionals at the point of care. Optimized AC management has the potential to reduce adverse drug events associated with anticoagulant therapy in the outpatient setting.

A community pharmacist-led anticoagulation management service: attitudes towards a new collaborative model of care in New Zealand†

Objective

To examine attitudes towards a new collaborative pharmacy-based model of care for management of warfarin treatment in the community. As background to the study, the New Zealand health authorities are encouraging greater clinical involvement of community pharmacists.

Methods

Fifteen community pharmacies in New Zealand took part in a community pharmacist-led anticoagulation management service (CPAMS). Participants (patients, general practitioners, practice nurses, pharmacists) were surveyed on their views on accessibility, convenience, confidence in the service, impact on warfarin control, impact on workloads, effect on relationships and whether the service should be further implemented. A small number from each group was interviewed on the same topics.

Key findings

Patients reported improved access, convenience, a preference for capillary testing, and the immediacy of the test result and dose changes. They indicated that they had a better understanding of their health problems. While sample sizes were small, the majority of general practitioners and practice nurses felt there were positive benefits for patients (convenience) and themselves (time saved) and expressed confidence in pharmacists' ability to provide the service. There were some concerns about potential loss of involvement in patient management. Pharmacists reported high levels of satisfaction with better use of their clinical knowledge in direct patient care and that their relationships with both patients and health professionals had improved.

Conclusions

The new model of care was highly valued by patients and supported by primary care practitioners. Wider implementation of CPAMS was strongly supported. Pharmacists and general practitioners involved in CPAMS reported a pre-existing collaborative relationship, and this appears to be important in effective implementation.

National assessment of warfarin anticoagulation therapy for stroke prevention in atrial fibrillation

BACKGROUND

Anticoagulation control with warfarin, as assessed by the international normalized ratio (INR), is challenging. Time in the therapeutic range has been inversely correlated with major hemorrhage, thrombosis, and mortality. Quest Diagnostics offers standardized INR laboratory testing services to approximately half of US physician practices. To inform national stroke prevention strategies, we evaluated anticoagulation control in office-based community practices.

METHODS AND RESULTS

We selected individuals with ≥2 months of INR data, INR results of >1.2, and an ICD-9 diagnosis code of atrial fibrillation. Frequency of INR testing and time in the therapeutic range were analyzed by age, sex, length of testing period, number of referred patients per provider, and median household income (based on home ZIP code). We identified 138 319 individuals referred by 37 939 physicians, yielding a total of 2 683 674 INR results. Patients had a mean age of 74 years; 81% were ≥65 years of age, and 55% were ≥75 years of age. The mean time in the therapeutic range was 53.7% overall and improved with time on treatment, increasing from 47.6% for patients with <6 months of testing to 57.5% for those with ≥6 months of testing (P<0.0001). The number of patients tested per physician practice was positively associated with time in the therapeutic range. Younger age, female sex, and lower income were also independently associated with poorer anticoagulant control.

CONCLUSION

This study demonstrates widespread suboptimal anticoagulation control, suggesting an urgent need to improve oral anticoagulation care for most patient segments in the United States.

Gaps in monitoring during oral anticoagulation: insights into care transitions, monitoring barriers, and medication nonadherence

BACKGROUND

Among patients receiving oral anticoagulation, a gap of &gt; 56 days between international normalized ratio tests suggests loss to follow-up that could lead to poor anticoagulation control and serious adverse events.

METHODS

We studied long-term oral anticoagulation care for 56,490 patients aged 65 years and older at 100 sites of care in the Veterans Health Administration. We used the rate of gaps in monitoring per patient-year to predict percentage time in therapeutic range (TTR) at the 100 sites.

RESULTS

Many patients (45%) had at least one gap in monitoring during an average of 1.6 years of observation; 5% had two or more gaps per year. The median gap duration was 74 days (interquartile range, 62-107). The average TTR for patients with two or more gaps per year was 10 percentage points lower than for patients without gaps (P &lt; .001). Patient-level predictors of gaps included nonwhite race, area poverty, greater distance from care, dementia, and major depression. Site-level gaps per patient-year varied from 0.19 to 1.78; each one-unit increase was associated with a 9.2 percentage point decrease in site-level TTR (P &lt; .001).

CONCLUSIONS

Site-level gap rates varied widely within an integrated care system. Sites with more gaps per patient-year had worse anticoagulation control. Strategies to address and reduce gaps in monitoring may improve anticoagulation control.

Prevention and treatment of venous thromboembolism in patients with cancer

BACKGROUND

Many patients who experience a venous thromboembolic event have cancer, and thrombosis is much more prevalent in patients with cancer than in those without it. Thrombosis is the second most common cause of death in cancer patients and cancer is associated with a high rate of recurrence of venous thromboembolism (VTE), bleeding, requirement for long-term anticoagulation and poorer quality of life.

METHODS

A literature review was conducted to identify guidelines and evidence pertaining to anticoagulation prophylaxis and treatment for patients with cancer, with the goal of identifying opportunities for pharmacists to advocate for and become more involved in the care of this population.

RESULTS

Many clinical trials and several guidelines providing guidance to clinicians in the treatment and prevention of VTE in patients with cancer were identified. Current clinical evidence and guidelines suggest that cancer patients receiving care in hospital with no contraindications should receive VTE prophylaxis with unfractionated heparin (UFH), a low-molecular-weight heparin (LMWH) or fondaparinux. Patients who require surgery for their cancer should receive prophylaxis with UFH, LMWH or fondaparinux. Cancer patients who have experienced a VTE event should receive prolonged anticoagulant therapy with LMWH (at least 3 months to 6 months). No routine prophylaxis is required for the majority of ambulatory patients with cancer who have not experienced a VTE event. Most publicly funded drug plans in Canada have developed criteria for funding of LMWH therapy for patients with cancer.

CONCLUSIONS

Evidence suggests that LMWH for 3 to 6 months is the preferred strategy for most cancer patients who have experienced a thromboembolic event and for hospital inpatients, but this is often not implemented in practice. Concerns about adherence with injectable therapy should not prevent use of these agents. Pharmacists should assess cancer patients for their risk of VTE and should advocate for optimal VTE pharmacotherapy as appropriate. If LMWH is the preferred agent, on the basis of the evidence, the pharmacist should educate the patients appropriately and work with the prescriber to ensure best care.

Rivaroxaban: practical considerations for ensuring safety and efficacy

Rivaroxaban is the first agent available within a new class of anticoagulants called direct factor Xa inhibitors. Rivaroxaban is approved for use in the United States for the prevention of stroke and systemic embolism in patients with nonvalvular atrial fibrillation, for the prevention of deep vein thrombosis in patients undergoing total hip replacement and total knee replacement, for the treatment of deep vein thrombosis and pulmonary embolism, and for the reduction in risk of recurrence of deep vein thrombosis and pulmonary embolism (with additional indications under review). Rivaroxaban dose and frequency of administration vary depending on the indication. As of result of predictable pharmacokinetics and pharmacodynamics, a fixed dose of rivaroxaban is administered without routine coagulation testing. Rivaroxaban has a short half-life, undergoes a dual mode of elimination (hepatic and renal), and is a substrate for P-glycoprotein. Rivaroxaban has a lower potential for drug interactions compared with warfarin. Despite the advantages of a once/day fixed-dose oral agent, in many clinical situations limited evidence is available to guide optimal management of rivaroxaban therapy. In this article, we review the available evidence and provide recommendations where possible for such situations including the desire to monitor the anticoagulation intensity, use in special patient populations, managing drug interactions, and transitioning across anticoagulant agents. Potential strategies for reversing rivaroxaban's anticoagulant effect are reviewed. Health systems will need to perform a systematic safety evaluation and ensure that numerous hospital policies related to anticoagulation are updated to include rivaroxaban. A comprehensive approach to education is needed for clinicians, patients, and technical support personnel involved in patient interactions to ensure safe use.

Delivery of optimized inpatient anticoagulation therapy: consensus statement from the anticoagulation forum

OBJECTIVE

To provide recommendations for optimized anticoagulant therapy in the inpatient setting and outline broad elements that need to be in place for effective management of anticoagulant therapy in hospitalized patients; the guidelines are designed to promote optimization of patient clinical outcomes while minimizing the risks for potential anticoagulation-related errors and adverse events.

DATA SOURCES

The medical literature was reviewed using MEDLINE (1946-January 2013), EMBASE (1980-January 2013), and PubMed (1947-January 2013) for topics and key words including, but not limited to, standards of practice, national guidelines, patient safety initiatives, and regulatory requirements pertaining to anticoagulant use in the inpatient setting. Non-English-language publications were excluded. Specific MeSH terms used include algorithms, anticoagulants/administration and dosage/adverse effects/therapeutic use, clinical protocols/standards, decision support systems, drug monitoring/methods, humans, inpatients, efficiency/ organizational, outcome and process assessment (health care), patient care team/organization and administration, program development/standards, quality improvement/organization and administration, thrombosis/ drug therapy, thrombosis/prevention and control, risk assessment/standards, patient safety/standards, and risk management/methods.

STUDY SELECTION AND DATA EXTRACTION

Because of this document's scope, the medical literature was searched using a variety of strategies. When possible, recommendations are supported by available evidence; however, because this paper deals with processes and systems of care, high-quality evidence (eg, controlled trials) is unavailable. In these cases, recommendations represent the consensus opinion of all authors and are endorsed by the Board of Directors of the Anticoagulation Forum, an organization dedicated to optimizing anticoagulation care. The board is composed of physicians, pharmacists, and nurses with demonstrated expertise and experience in the management of patients receiving anticoagulation therapy.

DATA SYNTHESIS

Recommendations for delivering optimized inpatient anticoagulation therapy were developed collaboratively by the authors and are summarized in 8 key areas: (1) process, (2) accountability, (3) integration, (4) standards of practice, (5) provider education and competency, (6) patient education, (7) care transitions, and (8) outcomes. Recommendations are intended to inform the development of coordinated care systems containing elements with demonstrated benefit in improvement of anticoagulation therapy outcomes. Recommendations for delivering optimized inpatient anticoagulation therapy are intended to apply to all clinicians involved in the care of hospitalized patients receiving anticoagulation therapy.

CONCLUSIONS

Anticoagulants are high-risk medications associated with a significant rate of medication errors among hospitalized patients. Several national organizations have introduced initiatives to reduce the likelihood of patient harm associated with the use of anticoagulants. Health care organizations are under increasing pressure to develop systems to ensure the safe and effective use of anticoagulants in the inpatient setting. This document provides consensus guidelines for anticoagulant therapy in the inpatient setting and serves as a companion document to prior guidelines relevant for outpatients.

Is there a role for warfarin anymore?

Reduction of atrial fibrillation–associated stroke risk has become the leading indication for warfarin use. Optimal management of warfarin can only be achieved with a relatively complex infrastructure. Alternative anticoagulant agents have been developed, and 3 have demonstrated effectiveness, safety, and adherence that are comparable or superior to warfarin in the clinical trial setting. None of the novel agents requires routine laboratory testing to demonstrate effective anticoagulation. Whereas these new agents present potential advantages, such as fixed dosing and dramatically reduced intracranial hemorrhaging, they are also subject to caveats that ought to be considered in the context of an “ideal” anticoagulant. If used casually, they have the potential to worsen rather than improve health care outcomes. There is little question that the management burden of the novel agents will be less than with warfarin. However, with a hemorrhagic risk that was similar to warfarin in these trials, there will likely remain a significant need for both baseline education and some level of focused interval follow-up to assess for bleeding risk and adherence considerations. These novel agents offer a definite advance in the available management options for thromboembolic disease, but until we understand the requirements for safe and effective use in the routine clinical setting, we will not be able to establish the extent to which they should replace warfarin.

The benefits of pharmacist-delivered warfarin education in the home

Objectives

Good warfarin knowledge is important for optimal patient outcomes, but barriers exist to effective education and warfarin knowledge is often poor. This study aimed to explore the educational outcomes of home-based warfarin education provided by trained pharmacists.

Methods

In a prospective, non-randomised, controlled cohort trial, patients received either usual community-based post-discharge care or a post-discharge warfarin management service, including warfarin education by trained pharmacists during two or three home visits. Patients’ warfarin knowledge was assessed at 8 and 90 days post-discharge using the Oral Anticoagulation Knowledge test.

Key findings

One hundred and thirty-nine patients were recruited into the usual care group between November 2008 and August 2009, and 129 into the intervention group between May and December 2009. Pharmacist-delivered warfarin education was associated with a significant difference between the intervention patients’ baseline and day 8 mean warfarin knowledge scores of 64.5% (95% confidence interval (CI) 61.0–68.5%) and 78.0% (95% CI 74.5–81.5%; P &lt; 0.001), respectively. The intervention patients also scored significantly higher than the usual care patients at day 8 (65.0%, 95% CI 61.5–68.0%; P &lt; 0.001), but not at day 90.

Conclusions

Use of an existing healthcare framework overcame several systemic barriers by facilitating warfarin education in patients’ homes. While the intervention was associated with better short-term warfarin knowledge, follow-up may be required to optimise its benefits. Widespread implementation of home-based warfarin education by pharmacists has the potential to contribute significantly to improved outcomes from warfarin therapy.

Anticoagulation management in the ambulatory surgical setting

Many people receiving maintenance anticoagulation therapy require surgery each year in ambulatory surgery centers. National safety organizations focus attention toward improving anticoagulation management, and the American College of Chest Physicians has established guidelines for appropriate anticoagulation management to balance the risk of thromboembolism when warfarin is discontinued with the risk of bleeding when anticoagulation therapy is maintained. The guidelines recommend that patients at high or moderate risk for thromboembolism should be bridged with subcutaneous low-molecular-weight heparin or IV unfractionated heparin with the interruption of warfarin, and low-risk patients may require subcutaneous low-molecular-weight heparin or no bridging with the interruption of warfarin. The guidelines recommend the continuation of warfarin for patients who are undergoing minor dermatologic or dental procedures or cataract removal. The literature reveals, however, that there is not adequate adherence to these recommendations and guidelines. Management of anticoagulation therapy by a nurse practitioner may improve compliance and safety in ambulatory surgery centers.

INR targets and site-level anticoagulation control: results from the Veterans AffaiRs Study to Improve Anticoagulation (VARIA)

BACKGROUND

Not all clinicians target the same International Normalized Ratio (INR) for patients with a guideline-recommended target range of 2-3. A patient's mean INR value suggests the INR that was actually targeted. We hypothesized that sites would vary by mean INR, and that sites of care with mean values nearest to 2.5 would achieve better anticoagulation control, as measured by per cent time in therapeutic range (TTR).

OBJECTIVES

To examine variations among sites in mean INR and the relationship with anticoagulation control in an integrated system of care.

PATIENTS/METHODS

We studied 103,897 patients receiving oral anticoagulation with an expected INR target between 2 and 3 at 100 Veterans Health Administration (VA) sites from 1 October 2006 to 30 September 2008. Key site-level variables were: proportion near 2.5 (that is, percentage of patients with mean INR between 2.3 and 2.7) and mean risk-adjusted TTR.

RESULTS

Site mean INR ranged from 2.22 to 2.89; proportion near 2.5, from 30 to 64%. Sites' proportions of patients near 2.5, below 2.3 and above 2.7 were consistent from year to year. A 10 percentage point increase in the proportion near 2.5 predicted a 3.8 percentage point increase in risk-adjusted TTR (P < 0.001).

CONCLUSIONS

Proportion of patients with mean INR near 2.5 is a site-level 'signature' of care and an implicit measure of targeted INR. This proportion varies by site and is strongly associated with site-level TTR. Our study suggests that sites wishing to improve TTR, and thereby improve patient outcomes, should avoid the explicit or implicit pursuit of non-standard INR targets.

Anticoagulation patient self-monitoring in the United States: considerations for clinical practice adoption

Systematic management models such as anticoagulation clinics have emerged in order to optimize warfarin effectiveness and to minimize related complications. Most of these models are structured so that patients come to a clinic for in-person testing and evaluation, thus making this model of care difficult to access and time consuming for many patients. The emergence of portable instruments for measuring anticoagulant effect in capillary whole blood made it possible for patients receiving warfarin to self-monitor the effect of their anticoagulant therapy. Self-monitoring empowers patients, offers the advantage of more frequent monitoring, and increases patient convenience by allowing testing at home and avoiding the need for frequent laboratory and clinic visits. Self-monitoring can entail patient self-testing (PST) and/or patient self-management (PSM). Several studies have evaluated and shown the benefit of both PST and PSM models of care when compared with either routine medical care or anticoagulation clinic management of anticoagulation therapy. Self-monitoring (PSM and/or PST) of anticoagulation results in lower thromboembolic events, lower mortality, and no increase in major bleeding when compared with standard care. Despite favorable results and enhanced patient convenience, the adoption of self-monitoring into clinical practice in the United States has been limited, especially in higher risk, disadvantaged populations. Although the emergence of a multitude of novel oral anticoagulants will permit clinicians to better individualize anticoagulant therapy options by choosing the optimum regimen based on individual patient characteristics, it is also expected that traditional agents will continue to play a role in a significant subset of patients. For those patients treated with traditional anticoagulants such as warfarin, future models of care will entail patient-centered management such as PST and PSM. The incorporation of technology (i.e., Web-based expert systems) is expected to further improve the outcomes realized by PST and PSM. Further studies are needed to explore factors that influence the adoption of self-monitoring in the United States and to evaluate the feasibility and implementation in real-life clinical settings.

Effects of CYP4F2 polymorphism on response to warfarin during induction phase: a prospective, open-label, observational cohort study

BACKGROUND

The cytochrome P450 (CYP) 4F2 isozyme has been reported to metabolize vitamin K(1) in vitro, and the V433M polymorphism in the CYP4F2 gene has been associated with reduced vitamin K(1) metabolism and the need for a higher maintenance dosage in patients receiving warfarin.

OBJECTIVE

The purpose of the present study was to evaluate the effects of V433M polymorphism on warfarin response during the induction phase.

METHODS

Warfarin-naive white patients in whom warfarin was scheduled to be initiated with a target INR of 2 to 3 were enrolled into the study. On enrollment, a single blood sample for the genotyping of CYP4F2, CYP2C9, and VKORC1 was drawn. The international normalized ratio (INR) was followed daily during induction and twice weekly until stable anticoagulation was reached. The relationships between several markers of warfarin response during induction and CYP4F2 polymorphism were determined.

RESULTS

The cohort consisted of 241 patients (115 men; mean [SD] age, 55.2 [19.4] years; weight, 79.5 [18.3] kg). Most of the patients were carriers of the CYP4F2 CC genotype (112 patients) or the CT genotype (104 patients). In carriers of the TT genotype (25 patients), INR >3 was >4-fold lower compared with that in carriers of the CC or CT genotype, suggesting that patients with the TT genotype were less sensitive to warfarin during induction. Also in TT carriers, the extent of excessive anticoagulation was >10-fold lower than in the other carriers. Both of these findings had a nominal P value of <0.05. After adjustment for false discovery rate, none of the findings remained significant at a threshold q value of <0.05. Among CC carriers, the concurrent use of a statin was associated with a 1-mg/d reduction in warfarin maintenance dosage. No similar effect was noted in the CT or TT carriers, suggesting a possible genetic influence on warfarin-statin interaction.

CONCLUSIONS

These preliminary findings suggest that among white patients treated with warfarin, CYP4F2 polymorphism had a measurable effect on warfarin responsiveness during induction; however, the observed differences failed to reach the level of statistical significance. The possibility that the effect of statins on warfarin anticoagulation varies among carriers of different CYP4F2 genotypes could not be excluded and should be evaluated further in a larger patient sample.

Organizational characteristics of high- and low-performing anticoagulation clinics in the Veterans Health Administration

OBJECTIVE

Anticoagulation clinics (ACCs) can improve anticoagulation control and prevent adverse events. However, ACCs vary widely in their performance on anticoagulation control. Our objective was to compare the organization and management of top-performing with that of bottom-performing ACCs.

DATA SOURCES/STUDY SETTING

Three high outlier and three low outlier ACCs in the Veterans Health Administration (VA).

STUDY DESIGN

Site visits with qualitative data collection and analysis.

DATA COLLECTION/EXTRACTION METHODS

We conducted semi-structured interviews with ACC staff regarding work flow, staffing, organization, and quality assurance efforts. We also observed ACC operations and collected documents, such as the clinic protocol. We used grounded thematic analysis to examine site-level factors associated with high and low outlier status.

PRINCIPAL FINDINGS

High outlier sites were characterized by (1) adequate (pharmacist) staffing and effective use of (nonpharmacist) support personnel; (2) innovation to standardize clinical practice around evidence-based guidelines; (3) the presence of a quality champion for the ACC; (4) higher staff qualifications; (5) a climate of ongoing group learning; and (6) internal efforts to measure performance. Although high outliers had all of these features, no low outlier had more than two of them.

CONCLUSIONS

The top-performing ACCs in the VA system shared six relatively recognizable characteristics. Efforts to improve performance should focus on these domains.