To the Editor.—The article by Dr Hylek et al1 brings a wealth of much-needed information to clinicians managing individual patients (usual clinical practice) and to specialized anticoagulant therapy units. Even though no randomized trial data exist, anticoagulant therapy units seem to improve clinical outcomes and decrease costs.2 Such units provide closer follow-up of patients, focused teaching, dietary management, and detailed review of factors that affect warfarin metabolism. Usual clinical practice may not provide such levels of care.
Carlos Estrada. Acetaminophen and Risk Factors for Excess Anticoagulation With Warfarin. JAMA. 1998;280(8):695–697. doi:10.1001/jama.280.8.695