Abstracts

In an earlier study we showed that patients diagnosed with psychogenic nonepileptic seizures (PNES) at our facility had a dramatic decrease or cessation of nonepileptic seizure events in the 24-hour period after patients were informed of their diagnosis using the Shen protocol. We suggested that a follow up study should evaluate whether the decrease was maintained over time, and whether cessation of PNES was followed by the development of other psychiatric or somatic complaints. This study addresses these points. Study subjects were chosen consecutively from the database of all patients admitted to the UC Davis Medical Center inpatient video-EEG monitoring unit from January 2000 through March 2004. Definitive diagnosis of PNES required vEEG monitoring in which the patient was observed having typical seizures without accompanying abnormality on EEG, and family members or witnesses familiar with the patient[rsquo]s events agreed that the recorded episodes were typical events. 53 patients were eligible for the study. Three physicians with standardized protocol training contacted subjects by telephone and administered a 15-item survey about their PNES and other factors. Survey results were analyzed using the SPSS for Windows program. Of the 52 eligible patients, 23 patients (44%) completed the survey, 25 patients (48%) were lost to follow up, 2 patients (4%) declined to participate and 2 patients (4%) were in jail. There was no significant difference in age between participants and non-participants (p = 0.42), but participants were more likely to be female (p = 0.01, t test). Mean length of follow up since diagnosis of PNES was 17.3 months (range 2-60 months). Three patients (13%) were seizure-free; 15 patients (65%) had a greater than 50% reduction in seizure frequency; 5 patients (22%) were having the same or greater frequency of seizures. 20 of 23 patients (87%) were still having some PNES. Patients were categorized as responders (more than 50% reduction in seizure frequency) or nonresponders (increase, no change or less than 50% decrease in seizure frequency). Responders were more likely to believe the diagnosis of nonepileptic seizures at the time of the survey than nonresponders (p [lt] 0.001, t test) and were less likely to be on disability (p = 0.04, t test). There were nonsignificant trends indicating that responders were less likely to have other somatization symptoms and were more likely to have experienced abuse. They did not differ in rates of AED use ([sim]40%), psychotropic use ([sim]80%), emergency visits for NES ([sim]30%) or comorbid psychiatric diagnoses ([sim]78%). Results suggest that the substantial decrease in NES frequency shortly after diagnosis is not maintained long term, but that the majority responded well with a greater than 50% reduction in seizure frequency from before diagnosis.