Abstracts

Rationale: In recent years, antiepileptic drugs (AEDs) have expanding indications beyond epilepsy, including neuropathies, bipolar disorder, Willis-Ekbom Disease (formally known as RLS), and migraine prophylaxis. However, many of these medications have side effects such as edema/weight gain, dysrhythmias, prolonged PR interval, and electrolyte or lipid alterations, which are of particular concern in patients with congestive heart failure (CHF) and atrioventricular (AV) block. There are currently about 5.7 million people in the US living with CHF and 4.9 million living with some degree of AV block (1). However, guidelines for how to prescribe AEDs in this population have not been published and clinical trials typically exclude these patients. The following commonly used AEDs have documented side effects, which may place these patients at risk: CBZ, EZG, GBP, LCM, LTG, PGB, RUF and VPA. Our hypothesis is that these AEDs will increase the risk of disease progression in patients with CHF and AV Block.Methods: The goals of this project are to better describe this population and determine what, if any, are the risks posed by the use of AEDs. Descriptive statistics are being collected on patients with a diagnosis of CHF or AV Block and an indication for treatment with an AED, identified through the University of Colorado Hospital electronic medical records database. Based on this database, a retrospective cohort study is being conducted to determine the relative risk of exacerbation, hospitalization and CV death for patients on an AED with serious cardiac side effects.Results: Based on a preliminary review of patient records, we identified 2978 patients with a diagnosis of heart failure or heart block. Of these, 15% (444 patients) also had an indication for an AED, including epilepsy, Willis-Ekbom Disease, migraines or neuropathies. The most common single indication was diabetic peripheral neuropathy (30%). As a group, neuropathies accounted for 60% of CHF/AV block patients with an indication for an AED.Conclusions: While more data is needed to clarify the risks, this is clearly a sizeable proportion of patients, an estimated 1.6 million in the US, with CHF or AV block who are prescribed AEDs. One of the most popular drugs for peripheral neuropathies, pregabalin, commonly causes peripheral edema and has been associated in case reports with heart failure exacerbation (2). If this proves to be a real safety concern, then there could be a significant number of patients at risk. With a growing number of patients living with heart disease and more uses for AEDs outside of epilepsy, there is more need than ever for data on the safety of these medications in this patient population. References: 1. Roger VL, Go AS, Lloyd-Jones DM, Benjamin EJ, Berry JD, Borden WB, et al. Heart disease and stroke statistics 2012 update: a report from the American Heart Association. Circulation. 2012; 125(1):e2 220. 2. Page RL 2nd, Cantu M, Lindenfeld J, Hergott LJ, Lowes BD. Possible heart failure exacerbation associated with pregabalin: case discussion and literature review. J Cardiovasc Med (Hagerstown). 2008 Sep;9(9): 922-5.