Atrial fibrillation (AF) increases risk of stroke up to 5 folds, resulting in considerable physical, cognitive impairment and high mortality1. Thus, AF related strokes are very expensive to treat compared to non-AF strokes2. Oral anticoagulation is a well-established therapy in the majority of stroke cases3. Warfarin reduces the risk of stroke by 64% and mortality by 30% compared to placebo3.
Recent data from the pinnacle registry presented by ‘Roopinder Sandhu, Edmonton, AB, Canada’ at the Scientific Sessions 2018, highlighted three key challenges in anti-coagulants management in stroke patients4. Data from a national outpatient registry reported over 700,000 patients had a diagnosis of atrial fibrillation5. Although oral anticoagulation use increased over time, around 40% of patients who are eligible for anti-coagulation never got started on therapy5. The second gap is sub-therapeutic dosing. Recent data from the orbit registry evaluated over 5700 patients who were recently started on a new drug and reported that one in eight patients were either underdosed or overdosed6. Further, there was a higher rate of adverse events in patients who had dosing that was sub therapeutic. The third gap is non-adherence. Data from administrative claims based on a large U.S. commercial insurance database, calculated adherence based on the fill date and the days of supply on the pharmacy claims over a median of 1.1 years7. Less than half of patients who were started on a drug therapy reached the threshold of proportion days covered of 80% or higher. This proportion was less for patients who were on Warfarin.
Given the public health consequences of untreated AF, it is necessary to evaluate different strategies to deliver stroke prevention therapy. Data from 30 randomized clinical trials evaluating the impact of pharmacists, versus standard care, showed superior results in the pharmacist care group in reducing systolic blood pressure (by 8 mm HG), diastolic blood pressure (by 4 mm HG) and total cholesterol (by 17 milligrams DL) and LDL (by 13 mg DL)10. This was done through educational intervention and identification of drug related problems followed by early feedback to the treating physician.
Roopinder added a few possible explanations to what could be driving such impact in the Canadian setting. Typically, a general practitioner would be dealing with patients with a higher evidence of chronic diseases. Further, patient demands often exceed the available physician capacity.
While these results collectively suggest that pharmacist led strategies may be a promising way forward because of their accessibility, drug expertise and their ability to build a trusted relationship. A few key things should be considered. First, that anticoagulation remains to be a complicated problem when it comes to individual patients, with many factors playing a role in the decision process including; medical history (as prior bleeding) and patient preferences. Second, while these interventions seem beneficial in the short-term it may lead to the same shortcomings in the long-term with the increase in demand on the pharmacists as the main provider.
Finally, a key question remains, would a collaborative approach between physicians and pharmacists yield better outcomes through reducing the burden on both providers and simultaneously increasing the time allocated to stroke patients on a case-by-case basis?
- Developed with the special contribution of the European Heart Rhythm Association (EHRA), Endorsed by the European Association for Cardio-Thoracic Surgery (EACTS), Authors/Task Force Members, Camm, A. J., Kirchhof, P., Lip, G. Y., … & Al-Attar, N. (2010). Guidelines for the management of atrial fibrillation: the Task Force for the Management of Atrial Fibrillation of the European Society of Cardiology (ESC). European heart journal, 31(19), 2369-2429.
- Stewart, S., Murphy, N., Walker, A., McGuire, A., & McMurray, J. J. V. (2004). Cost of an emerging epidemic: an economic analysis of atrial fibrillation in the UK. Heart, 90(3), 286-292.
- Ruff, C. T., Giugliano, R. P., Braunwald, E., Hoffman, E. B., Deenadayalu, N., Ezekowitz, M. D., … & Yamashita, T. (2014). Comparison of the efficacy and safety of new oral anticoagulants with warfarin in patients with atrial fibrillation: a meta-analysis of randomised trials. The Lancet, 383(9921), 955-962.
- Sandhu, R. K., Guirguis, L. M., Bungard, T. J., Youngson, E., Dolovich, L., Brehaut, J. C., … & McAlister, F. A. (2018). Evaluating the potential for pharmacists to prescribe oral anticoagulants for atrial fibrillation. Canadian Pharmacists Journal/Revue des Pharmaciens du Canada, 151(1), 51-61.
- Marzec, L. N., Wang, J., Shah, N. D., Chan, P. S., Ting, H. H., Gosch, K. L., … & Maddox, T. M. (2017). Influence of direct oral anticoagulants on rates of oral anticoagulation for atrial fibrillation. Journal of the American College of Cardiology, 69(20), 2475-2484.
- Steinberg, B. A., Peterson, E. D., Kim, S., Thomas, L., Gersh, B. J., Fonarow, G. C., … & Piccini, J. P. (2015). Use and outcomes associated with bridging during anticoagulation interruptions in patients with atrial fibrillation: findings from the Outcomes Registry for Better Informed Treatment of Atrial Fibrillation (ORBIT-AF). Circulation, 131(5), 488-494.
- Yao, X., Abraham, N. S., Alexander, G. C., Crown, W., Montori, V. M., Sangaralingham, L. R., … & Noseworthy, P. A. (2016). Effect of adherence to oral anticoagulants on risk of stroke and major bleeding among patients with atrial fibrillation. Journal of the American Heart Association, 5(2), e003074.
- Santschi, V., Chiolero, A., Burnand, B., Colosimo, A. L., & Paradis, G. (2011). Impact of pharmacist care in the management of cardiovascular disease risk factors: a systematic review and meta-analysis of randomized trials. Archives of internal medicine, 171(16), 1441-1453.