Abstracts

Rationale: The incidence of epilepsy is the highest in the elderly population (age ≥ 60 years). Moreover, the prevalence of epilepsy is higher in nursing home residents than in the general population¹. The objective of our study was to identify the most commonly prescribed antiepilepsy drugs (AED) in elderly nursing home residents. Methods: The data for this study was obtained from a pharmacy database serving Minnesota and Wisconsin nursing homes and consisting of 3,024 (978 male / 2,046 female) residents taking at least one AED. Data represent patient profiles obtained on a day in October of 2013. Descriptive statistics were performed with the statistical software R (version 2.11.1) to determine the frequency and the type of AEDs prescribed by age, gender, formulation type, trademarked/generic drugs, and route of administration. Results: The age of the nursing home residents in this study ranged from 60 to113 years. The most commonly prescribed AEDs were gabapentin (49.6%), divalproex sodium (19%), levetiracetam (12.7%), clonazepam (11.8%), and phenytoin (6.3%). There were no major differences in the prescribing patterns by gender or age of gabapentin and divalproex sodium. Most of the residents were prescribed generic compared to trademarked drugs except for pregabalin. Liquid formulations were prescribed in 4.8% of the residents. All the residents were prescribed AEDs for the oral route of administration except for diazepam for which all the patients were prescribed the rectal formulation. Conclusions: Phenytoin was previously ranked as the most frequently prescribed AED in nursing homes^1-3. Our present study indicates that AEDs such as gabapentin, divalproex sodium, levetiracetam, and clonazepam are currently prescribed more often than phenytoin in elderly nursing home residents. For all the AEDs, most of the patients were prescribed generic drugs and solid formulations compared to trademarked drugs and liquid formulations, respectively. 1. Garrard, J., et al. Factors associated with antiepileptic drug use among elderly nursing home residents. The journals of gerontology. Series A, Biological sciences and medical sciences 55, M384-392 (2000). 2. Schachter, S.C., et al. An evaluation of antiepileptic drug therapy in nursing facilities. Journal of the American Geriatrics Society 46, 1137-1141 (1998). 3. Leppik, I.E. & Birnbaum, A.K. Epilepsy in the elderly. Ann N Y Acad Sci 1184, 208-224 (2010). Acknowledgement: We would like to thank Merwin LTC Pharmacy.