Potentially Inappropriate Antiepileptic Drugs for Elderly Patients with Epilepsy Mary Jo V. Pugh, PhD, RN, à Joyce Cramer, BS, z Janice Knoefel, MD, MPH, z § Andrea Charbonneau, MD, MSc, à k Alan Mandell, MD, zw Lewis Kazis, DSc, Ãà and Dan Berlowitz, MD, MPH Ãà OBJECTIVES: To describe prescribing patterns for older veterans with epilepsy, determine whether disparity exists between these patterns and clinical recommendations, and describe those at greatest risk of receiving potentially inappropriate antiepileptic drugs (AEDs). DESIGN: Retrospective administrative database analysis. SETTING: All outpatient facilities within the Department of Veterans Affairs (VA). PARTICIPANTS: All veterans aged 65 and older who had epilepsy diagnosed before the end of fiscal year 1999 (FY99) and who received AEDs from the VA in FY99 (N 5 21,435). MEASUREMENTS: National VA pharmacy data were used to determine the AED regimen based on the AEDs patients received during the year. Administrative data were used to describe demographic variables and to gauge disease severity and epilepsy onset. RESULTS: Approximately 17% of patients received phe- nobarbital and 54% phenytoin. Patients classified as having newly diagnosed disease were less likely to receive phenobarbital monotherapy and combination therapy and more likely to receive gabapentin or lamotrigine mono- therapy (w 2 5 288.90, Po.001). Logistic regression anal- yses indicated that, for all patients, those with more severe disease were less likely to receive phenobarbital mono- therapy than other monotherapy and phenobarbital com- binations than other combinations. Those who received specialty consultation were less likely to receive phenytoin monotherapy than AED monotherapy, which is consistent with clinical recommendations. CONCLUSION: Most older veterans received potentially inappropriate AED therapy. Hence, the standard of care for older patients with epilepsy should be reevaluated, although the vast use of phenytoin in this population suggests that change in practice patterns may be difficult. J Am Geriatr Soc 52:417–422, 2004. Key words: epilepsy; drug therapy; adverse effects; quality of care; geriatrics M edical treatment for epilepsy has changed consider- ably in the past 2 decades because of clinical research findings and the development of new antiepileptic drugs (AEDs). In 1983, a systematic assessment of the frequency and severity of adverse effects 1 showed differences between the standard AEDs (phenobarbital, primidone, phenytoin, carbamazepine, and valproate). Two landmark studies from the Department of Veterans Affairs (VA) extended this assessment by comparing AEDs in head-to-head randomized clinical trials. The first study 2,3 identified phenobarbital and primidone as undesirable first-line AEDs because of their higher burden of adverse effects. Although carbamazepine and phenytoin were similarly effective, phenytoin patients experienced significantly more adverse cognitive effects. 3 The second trial comparing carbamaze- pine and valproate 4 found equal efficacy but slightly different adverse-effect profiles. Thus, carbamazepine, phenytoin, and valproate have been favored for first-line use in the general population. 5–7 In recent years, new AEDs that combine high efficacy with a low incidence of adverse effects have been developed (gabapentin, lamotrigine, levetiracetam, oxcarbazepine, tiagabine, topiramate, zonisamide). Few studies have directly compared these new AEDs with standard AEDs, 5,6 and even fewer have examined these effects in the elderly, 8–10 but general studies of pharmacokinetics and pharmacody- namics suggest that the properties of the newer AEDs make them more suitable than phenytoin for use in elderly patients 5 because the pharmacokinetic profile of phenytoin This research was supported by a Veterans Health Administration Health Services Research and Development postdoctoral fellowship award to the first author. Address correspondence to Mary Jo V. Pugh, PhD, RN, CHQOER, Bedford VAMC (152), 200 Springs Road, Bedford, MA 01730. E-mail: address mjpugh@bu.edu From the à Center for Health Quality, Outcomes, and Economic Research and w Department of Neurology, Bedford Veterans Affairs Medical Center, Bedford, Massachusetts; z Yale University, Department of Psychiatry, New Haven, Connecticut; z New Mexico Veterans Healthcare System, Medicine Service, Albuquerque, New Mexico; § University of New Mexico, Departments of Internal Medicine and Neurology, Albuquerque, New Mexico; k Boston Medical Center, Department of General Internal Medicine, Boston, Massachusetts; z Boston University School of Medicine, Department of Neurology, Boston, Massachusetts; and Ãà Boston University School of Public Health, Department of Health Services, Boston, Massachusetts. JAGS 52:417–422, 2004 r 2004 by the American Geriatrics Society 0002-8614/04/$15.00