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SDP 12-249 – HSR Study

SDP 12-249
Improving Anticoagulation Control in VISN 1
Ann M. Borzecki, MD MPH
VA Bedford HealthCare System, Bedford, MA
Bedford, MA
Funding Period: October 2012 - September 2016
Over 100,000 VA patients receive oral anticoagulation (AC) with warfarin each year to prevent blood clots, including strokes. AC is safer and more effective when it is managed skillfully and therefore well-controlled. AC control can be measured using percent time in therapeutic range (TTR), the proportion of time when patients are sufficiently anticoagulated to prevent clots but not excessively anticoagulated (which increases the risk of bleeding). We have shown that the anticoagulation clinics (ACCs) of the VA vary widely on TTR, from 40% (very poor control) to 70% (excellent control). Improving TTR in the VA would prevent thousands of adverse events, including strokes, major hemorrhages, and deaths. We have further investigated the structures and processes of care that contribute to these wide disparities in TTR performance.

We applied proven methods to change provider behavior. The goal was to facilitate the adoption of these evidence-based practices in order to improve TTR in VISN 1. We utilized educational outreach, audit and feedback, internal facilitation, and external facilitation to promote improvements in three evidence-based processes of care; namely, follow-up within 7 days after deranged INR values, minimizing loss to follow-up, and use of guideline concordant INR targets.

Our clinician-focused intervention used a Dashboard to measure site-level TTR and processes of care and an Algorithm for routine AC management. Both the Dashboard and the Algorithm are concrete representations of our main evidence-based recommendations to improve AC management. We promoted their use through quarterly visits to the sites, at which we delivered audit and feedback and educational outreach, and also provided external facilitation to address ways to improve these performance measures. Our main outcome was change in site TTR over time, which was compared between VISN 1 and non-VISN 1 sites using an interrupted time series. Secondary outcomes included site-level changes in processes of anticoagulation care (measured using automated data). We used a difference-in-differences (DID) model to examine changes in anticoagulation control, measured as percent time in target range (TTR), as well as process measures, and compared VISN 1 sites to 116 VA sites located outside VISN 1. The pre-intervention period was from 5/1/10-5/1/13, while the post-intervention period was from 5/2/13-5/10/16.

During the study period, 11,794 patients with a diagnosis of atrial fibrillation or venous thromboembolism were anticoagulated with warfarin within VISN 1 (our intervention region) for at least part of the study period. Outside VISN 1, 248,782 patients with these diagnoses received warfarin for at least part of the study period. TTR for the pre-intervention period was 66.4% within VISN 1 and 65.9% outside VISN 1 (p = 0.02 for difference). The average TTR in VISN 1 increased by 2.8% from the pre- to the post-period, while the average TTR outside VISN 1 increased by 0.5%. The DID analysis showed that TTR increased 2.3% more in VISN 1 (p < 0.001 for difference). Among all 21 VISNs, VISN 1 went from being ranked 8th on pre-period TTR (66.4%) to 3rd on post-period TTR (69.2%). Most targeted processes of care also improved within VISN 1. The proportion of patients with follow-up within 7 days of low INRs ( 1.5) increased by 15% within VISN 1 and by 2% outside VISN 1 (p < 0.001). Similarly, the proportion of patients with follow-up within 7 days of high INRs ( 4.0) increased by 15% within VISN 1 and did not change outside VISN 1 (p < 0.001). The rate of gaps in monitoring per patient-year of follow-up decreased by 0.03 inside VISN 1 and by 0.01 outside VISN 1 (p = 0.43). Finally, the proportion of patients with mean INR 2.3-2.7 increased by 6% within VISN 1 and by 1% outside VISN 1 (p = 0.002).
For the evaluation of process implementation, we collected data at yearly intervals throughout the project. Data collection has included staff interviews, observation of clinical operations, and collection of the Organizational Readiness to Change (ORCA) instrument. Longitudinal analysis has revealed considerable progression from the baseline, pre-implementation state to the end of the project. All 8 VISN sites have been quite changed by the ongoing intervention, and all have developed mechanisms to promote their own improvement. One universal finding is that the availability of performance measurement and registry functions has changed how sites look at their practice in ways that are likely irreversible.

Our project has demonstrated that through consistent effort, it is possible to greatly improve outcomes of warfarin management in VHA. The ideas driving this project are reflected in the 2015 VHA Anticoagulation Directive, including warfarin management algorithms, staffing recommendations, and numerous other best practices for how to run a high-functioning warfarin management service. Possibly most important of all, PBM is in the final stages of standing up a national dashboard to monitor warfarin, patterned on the one we used for VISN 1 in this project. This national spread will enable patients across VHA to benefit from improved outcomes, in large part as a result of this project. Our project also has implications beyond the management of warfarin, because clinical pharmacy is a relatively new discipline and relatively new to this kind of quality improvement. We have already seen alumni of this project applying their newly gained quality improvement skills to other projects within clinical pharmacy in VISN 1.

External Links for this Project

NIH Reporter

Grant Number: I01HX001001-01

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Journal Articles

  1. Rose AJ, McCullough MB. A Practical Guide to Using the Positive Deviance Method in Health Services Research. Health services research. 2017 Jun 1; 52(3):1207-1222. [view]
  2. Rose AJ, Park A, Gillespie C, Van Deusen Lukas C, Ozonoff A, Petrakis BA, Reisman JI, Borzecki AM, Benedict AJ, Lukesh WN, Schmoke TJ, Jones EA, Morreale AP, Ourth HL, Schlosser JE, Mayo-Smith MF, Allen AL, Witt DM, Helfrich CD, McCullough MB. Results of a Regional Effort to Improve Warfarin Management. The Annals of pharmacotherapy. 2017 May 1; 51(5):373-379. [view]
Magazine/Popular Press Articles

  1. Rose AJ, Hylek EM, Berlowitz DR. Measuring and Improving Quality of Oral Anticoagulation for Veterans. Federal Practitioner. 2013 Mar 1; 3(3):34-6. [view]
Conference Presentations

  1. McCullough MB, Solomon JL, Petrakis BA, Rose AJ. Clinical Pharmacy and the Social Life of Medication: An Ethnographic Exploration of Policy and Practice in the VA. Poster session presented at: American Anthropological Association Annual Meeting; 2014 Dec 4; Washington, DC. [view]
  2. McCullough M, Fix GM, Kim B, Wang S, Ruben M. Direct Observation Methods for Health Services and Implementation Research. Presented at: VA HSR&D / QUERI National Meeting; 2015 Jul 5; Washington DC. [view]
  3. Benedict A, Rose AJ, Park A, Fu A, Schlosser J. Evaluation of Multiple Anticoagulation Delivery Methods using Observations and Time Studies. Paper presented at: Industrial and Systems Engineering Research Conference; 2013 May 18; San Juan, PR. [view]
  4. McCullough M, Gillespie C, Petrakis BA, VanDeusen-Lukas C, Rose AJ. Forming and Activating an Internal Facilitation Group for Successful Implementation in Clinical Pharmacy: A Qualitative Study. Poster session presented at: AcademyHealth Annual Research Meeting; 2016 Jun 20; Boston, MA. [view]
  5. McCullough MB, Petrakis BA, Gillespie CK, Park AM, Lukas CV, Rose AJ. Introducing a new performance measure into practice: Attitude and behavior shifts among frontline staff. Poster session presented at: VA HSR&D / QUERI National Meeting; 2015 Jul 9; Philadelphia, PA. [view]
  6. McCullough M, Solomon J, Petrakis BA, Rose AJ. Middle managers, micro-practices and change: Examining the dynamics between implementation and leadership in an anticoagulation care improvement initiative. Paper presented at: Society for Applied Anthropology Annual Meeting; 2014 Mar 21; Albuquerque, NM. [view]
  7. McCullough M, Benzer JK, Charns MP, Rose AJ. Saying yes but meaning no: Middle manager avoidant leadership strategies in the implementation of an evidence-based intervention. Poster session presented at: AcademyHealth Annual Research Meeting; 2014 Jun 8; San Diego, CA. [view]
  8. McCullough MB, Chou AF, Solomon JL, Petrakis BA, Kim B, Hamilton A, Rose AJ. The Interplay of Contextual Elements in Implementation: An Ethnographic Case Study. Poster session presented at: National Institutes of Health / AcademyHealth Conference on the Science of Dissemination and Implementation; 2014 Dec 8; Bethesda, MD. [view]

DRA: Cardiovascular Disease
DRE: Treatment - Efficacy/Effectiveness Clinical Trial
Keywords: none
MeSH Terms: none

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