Introduction

This chapter reviews the epidemiology and clinical presentation of status epilepticus (SE) in Richmond, Virginia. A database was established at Virginia Commonwealth University to accrue the first population-based information on the natural presentation of SE in a controlled and validated community setting. SE occurred with an absolute incidence of 41 patients per 100,000 population per year in Richmond, Virginia. The frequency of total SE occurrences was 50 patients per 100,000 residents per year, and the overall mortality in this population was 22%. The elderly population had a mortality exceeding 38%. In addition, infants less than one year old were found to have the highest incidence of SE in the overall Richmond population, but the overall elderly population as a major age group had the largest number of cases in comparison to pediatric and young adult cases. The absolute incidence and occurrences of SE in this population proved to be underestimates because of inability (for various reasons) to document all cases of SE. Using validation mechanisms, the underreporting of SE in hospital charts and by physicians was corrected, and estimates for the occurrence of SE were obtained. Extrapolating from the Richmond database, more than 4.5 million cases of SE occur worldwide every year, with almost 1 million deaths per year. The costs associated with SE in the United States may exceed $4.5 billion annually. These figures—prevalence rates and costs—indicate not only the severity and significance of clinical SE, but also the potential costs to society in terms of dollars and chronic health care problems. In Richmond, nonwhite patients had a much higher incidence of and mortality from SE than white patients. Partial SE was the most common form of seizure initiating SE, and generalized tonic-clonic SE was the most common final stage of seizure type in SE. Age, etiology, and seizure duration were found to contribute to mortality. Acute and remote cerebrovascular accidents were the major causes in adults, and infections with fever were the most common cause in children. A significant number of individuals with SE had no previous history of epilepsy. In the elderly population, 70% of the patients had no previous history of epilepsy. The role of the genetic predisposition to develop SE in contributing to the frequency and presentation of SE in the population is presented. The results of this study provide a summary of the first population-based epidemiological study on SE and provide important clinical features and outcome data on this major medical and neurological condition presenting in both academic and community hospital settings in the Richmond, Virginia, area.