Objectives. Falling Down on Warfarin Therapy. CHADS 2 Score. CHADS 2 & CHA 2 DS 2 -VASc Score. HAS-BLED Score 04/08/2014. Real World Application

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1 Falling Down on Warfarin Therapy David Andrew Jacob, PharmD Pharmacy Resident Dayton VA Medical Center Dayton, Ohio Objectives Describe CHADS 2 score and the decision to anticoagulate patients with AFib Describe role of HAS-BLED in risk stratification assessment for safety of anticoagulation Discuss physician providers view points on warfarin in high fall risk/elderly patients Summarize the evidence of risk of hemorrhagic stroke vs. ischemic stroke for high fall risk patients on warfarin CHADS 2 Score CHADS 2 & CHA 2 DS 2 -VASc Score Risk Stratification for AFib Patient s Risk of Stroke/Embolism CHADS 2 Congestive Heart Failure +1 Hypertension History (controlled or uncontrolled) +1 Age > 75 years old +1 Diabetes Mellitus +1 Stroke History +2 CHA 2 DS 2 -VASc Almost same as above, plus. Vascular Disease History +1 Age < 65 years old +0 > 65 & < 75 y/o +1 > 75 y/o +2 Sex Male +0 Female +1 Real World Application CHADS 2 Score Stroke Risk % per Year Score CHADS2 CHA2DS2-VASc One 2.8% 1.3% Two 4.0% 2.2% Three 5.9% 3.2% Four 8.5% 4.0% Five 12.5% 6.7% Six 18.2% 9.8% Seven 9.6% Eight 6.7% Nine 15.2% 2013 CHEST guidelines recommend anticoagulation with warfarin for patients with CHADS 2 score 1 Risk Stratification for AFib Patient s Risk of Major Bleed 1

HAS-BLED Hypertension History +1 Renal Disease +1 Liver Disease +1 Stroke History +1 Prior Major Bleed or Predisposition to Bleeding +1 Labile INR +1

4% Two 4.1% Three 5.8% Four 8.9% Five 9.1% Six > 5 Too Rare to Seven Determine Eight Risk Nine Factoring Fall Risk into Clinical Judgment!!! Difficult!

Falls risk was perceived to be an important barrier in nine of these studies.

2 HAS-BLED Hypertension History +1 Renal Disease +1 Liver Disease +1 Stroke History +1 Prior Major Bleed or Predisposition to Bleeding +1 Labile INR +1 Age 65 years old +1 Medication Usage Predisposing to Bleeding +1 Alcohol Usage History +1 Real World Application Score HAS-BLED Risk Zero 0.9% One 3.4% Two 4.1% Three 5.8% Four 8.9% Five 9.1% Six > 5 Too Rare to Seven Determine Eight Risk Nine Factoring Fall Risk into Clinical Judgment!!! Difficult!!! What is the opinion of our colleagues? Ten studies reported physicians views in relation to the risk of falls. Falls risk was perceived to be an important barrier in nine of these studies. In the remaining study, falls risk was considered a significant barrier to warfarin prescription by only 10% of general practitioners and 8% of cardiologists, The meaning of risk of falls was variable between papers, with the majority not providing a specific definition. 2

P I C O P I C O > 65 y/o, AFib, at risk for falling, but no other contraindications to antithrombotic therapy used to model outcomes Long-term warfarin use Long-term aspirin use No antithrombotic

studies 49 met inclusion criteria Assumed event rates from meta-analyses of Atrial Fibrillation Investigators (2000 patient-years of f/u) Annual stroke risk 6%, RRR= 21% ASA, 68% warfarin SDH and ICH

3 P I C O P I C O > 65 y/o, AFib, at risk for falling, but no other contraindications to antithrombotic therapy used to model outcomes Long-term warfarin use Long-term aspirin use No antithrombotic therapy Composite of possible outcomes (stroke, ICH, death) expressed in terms of QALYs (Man-Son-Hing, 1999) Methods Markov decision analytic model Systemic review of MEDLINE studies 190 relevant studies 49 met inclusion criteria Assumed event rates from meta-analyses of Atrial Fibrillation Investigators (2000 patient-years of f/u) Annual stroke risk 6%, RRR= 21% ASA, 68% warfarin SDH and ICH too few to get precise estimate for groups SHD rate in elderly = for every patient-year Rate of falls 33% of people, 1 fall within 1 year of f/u (Garwood, 2008) (Man-Son-Hing, 1999) (Man-Son-Hing, 1999) Non-Model Data Analysis of Real Patients (Garwood, 2008) 3

P I C O P I C O Medicare beneficiaries (x = 80 y/o) w/ AFib.

High Risk for falls (n=1245) Other patients with AFib (n=18,261) Subsequent

warfarin or aspirin at baseline did not significantly affect RISK of intracranial

4 P I C O P I C O Medicare beneficiaries (x = 80 y/o) w/ AFib. 48% of cohort on warfarin at hospital D/C. High Risk for falls (n=1245) Other patients with AFib (n=18,261) Subsequent hospitalization for ICH based on ICD-9 codes Warfarin Effect on ICH RISK Prescription of warfarin or aspirin at baseline did not significantly affect RISK of intracranial hemorrhage Hazard Ratio Confidence Interval Warfarin Aspirin Warfarin Effect on ICH Mortality 30-day mortality Warfarin 51.8% No Warfarin 33.6% (p=0.007) 4

5 How will this effect my practice? Fall risk will not be the end all justification for holding anticoagulation I will recommend consideration of other risk factors for ICH more to providers balancing clinical decision to continue anticoagulation. Prior stroke, prior bleed, neuropsychiatric impairment (schizophrenia, dementia, & PD) Reference Man-Son-Hing M. Choosing Antithrombotic Therapy for Elderly Patients With Atrial Fibrillation Who Are at Risk for Falls. Arch Intern Med. 1999;159(7): Garwood CL, Corbett TL. Use of anticoagulation in elderly patients with atrial fibrillation who are at risk for falls. Ann Pharmacother. 2008;42(4): Gage BF, Birman-deych E, Kerzner R, Radford MJ, Nilasena DS, Rich MW. Incidence of intracranial hemorrhage in patients with atrial fibrillation who are prone to fall. Am J Med. 2005;118(6): Lip GY, Frison L, Halperin JL, Lane DA. Comparative validation of a novel risk score for predicting bleeding risk in anticoagulated patients with atrial fibrillation: the HAS-BLED (Hypertension, Abnormal Renal/Liver Function, Stroke, Bleeding History or Predisposition, Labile INR, Elderly, Drugs/Alcohol Concomitantly) score. J Am Coll Cardiol. 2011;57(2): Lip GY, Nieuwlaat R, Pisters R, Lane DA, Crijns HJ. Refining clinical risk stratification for predicting stroke and thromboembolism in atrial fibrillation using a novel risk factor-based approach: the euro heart survey on atrial fibrillation. Chest. 2010;137(2):

Weighing the risk of stroke vs the risk of bleeding: Which AF patients should be anticoagulated?

Weighing the risk of stroke vs the risk of bleeding: Which AF patients should be anticoagulated? Albert L. Waldo, MD, PhD (Hon) The Walter H. Pritchard Professor of Cardiology, Professor of Medicine,and