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Articles: Margaret C. Fang, Yuchiao Chang, Elaine M. Hylek, Jonathan Rosand, Steven M. Greenberg, Alan S. Go, and Daniel E. Singer Advanced Age, Anticoagulation Intensity, and Risk for Intracranial Hemorrhage among Patients Taking Warfarin for Atrial Fibrillation Ann Intern Med 2004; 141: 745-752 [Abstract] [Full text] [PDF]

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Warfarin or not warfarin?

Francisco J Ruiz-Ruiz   (29 November 2004)

Risk of intracerebral hemorrhage is increased when aspirin is added to warfarin

Robert Hart   (17 November 2004)

Warfarin or not warfarin? 29 November 2004
Francisco J Ruiz-Ruiz, MD Hospital Clinico de Zaragoza, Spain Send rapid response to journal: Re: Warfarin or not warfarin? fruiz{at}comz.org Francisco J Ruiz-Ruiz	Warfarin or not warfarin? That is the question. Each day, this dilemma is considered by physicians who treat elderly patients, specially octogenarian. Benefits of warfarin are well known in patients at 75 years of age or older. But, they have a higher risk than younger patients for intracranial hemorrhage and other types of bleeding associated with warfarin. Fang et al establish the intracranial hemorrhage risk depend on age and INR (1). However, characteristics of these patients are not favourable to prescribe warfarin. INR control is more difficult in patients at 85 years of age or older due to several factors. So, a high percent of them suffer from gait disturbances, neurodegenerative diseases and others prevalent diseases (diabetes, COPD, heart failure, …). A lot of them take drugs such as amiodarone, antibiotics, corticoids, statins, omeprazol, NSAID, …, which can increase warfarin effect. Other patients present social problems that not guarantee a right monitoring. Because we treat patients and not percents or relative risk, I think to generalize recommendation about oral anticoagulation in very older patients should be avoided. According to associated diseases, concurrent medications, functional and mental status, … we should individualize prescription of anticoagulation. REFERENCES 1. Fang MC, Chang Y, Hylek EM, Rosand J, Greenberg SM, Go AS, et al. Advanced age, anticoagulation intensity, and risk for intracranial hemorrhage among patients taking warfarin for atrial fibrillation. Ann Intern Med 2004; 141: 745-52 Conflict of Interest: None declared
Risk of intracerebral hemorrhage is increased when aspirin is added to warfarin 17 November 2004
Robert Hart, MD University of Texas Health Science Center Send rapid response to journal: Re: Risk of intracerebral hemorrhage is increased when aspirin is added to warfarin hartr{at}uthscsa.edu Robert Hart	The case-control study by Fang et al. excluded 503 cases due to “lack of anticoagulation”.(1) Does this refer to “not receiving warfarin” or “no prolongation of the INR”? If it is the latter, the study systematically underestimates the risk of intracerebral hemorrhage at lower INRs. If it is the former, was the determination made with knowledge of the INR, potentially biasing the selection? Concomitant use of aspirin with anticoagulation did not emerge as a risk factor for intracranial hemorrhage in this study which did not consider duration of antithrombotic therapy, sharply conflicting with a meta-analysis of randomized trials (2), a longitudinal cohort study (3), and bivariate analysis of a under-powered case-control study (4) indicating a 2-3 fold increased risk of intracerebral hemorrhage when aspirin is added to warfarin. Considering all available data, concomitant use of aspirin is likely to increase the risk of warfarin-associated intracerebral hemorrhage, and this is important for clinicians to appreciate. Finally, the authors’ major conclusion that “anticoagulation management should focus on maintaining INRs in the 2.0-3.0 range…” is not supported strongly by their data because neither efficacy for thromboembolism prevention nor major extracranial bleeding were assessed. 1. Fang MC, Chang Y, Hylek EM, Rosand J, Greenberg SM, Go AS, Singer DE. Advanced age, anticoagulation intensity, and risk for intracranial hemorrhage among patients taking warfarin for atrial fibrillation. Ann Intern Med 2004; 141: 745-52. 2. Hart RG, Benavente O, Pearce LA. Increased risk of intracranial hemorrhage when aspirin is combined with warfarin: a meta-analysis and hypothesis. Cerebrovasc Dis 1999; 9: 215-17. 3. Shireman TI, Howard PA, Kresowik TF, Ellerbeck EF. Combined anticoagulant-antiplatelet use and major bleeding events in elderly atrial fibrillation patients. Stroke 2004; 35: 2362-7. 4. Berwaerts J, Webster J. Analysis of risk factors involved in oral- anticoagulant-related intracranial hemorrhages. Q J Med 2000; 93: 513-521. Conflict of Interest: None declared