Abstracts

Rationale: It is widely taught that diagnosis is revealed in the patient's history. "Listen to your patient, they are telling you the diagnosis," is a frequently quoted statement. However, a patient with spells is often, at least in part, not conscious or amnestic to the details of the event. Patients often describe the history based on what others have told them. In a court of law, this may be considered hearsay evidence and is potentially not admissible at trial. We hypothesized that eyewitnesses to spells may be more accurate than the patients themselves. We studied patients with spells referred to an epilepsy monitoring unit (EMU) and used the video and electroencephalogram as the gold standard. Methods: The study was performed prospectively at the University of Colorado Hospital (Denver) EMU. Patients and an eyewitness (usually a family member) were given a questionnaire of multiple semiologic features of the patient's events. The possible responses were "yes," "no" or "don't know," with a few exceptions (some questions addressed issues such as which hand was involved in an activity or which direction the patient turned, for example). All respondents had capacity for informed consented. Inclusion criteria included at least one typical event of good quality on video. We compared patient and eyewitness responses to the video gold standard to ascertain accuracy. T-tests were used for statistical comparison of means. Results: 33 patients and 33 witnesses were included. Two main end points were evaluated: total number of "don't know" responses in the two groups and total number of accurate responses to select questions (15 questions) in the groups compared to the gold standard video review. The mean number of "don't know" responses was higher in the patient group than the eyewitness group (29.57 [50.99%] vs 5.09 [8.77%] respectively) and this difference was significant (p-value = 2.09 x 10^-9). Eyewitnesses were found to have significantly more accurate responses than the patient group (8.45 (56.36%) vs. 5.45 [36.36%] respectively; p-value = 6.22 x 10^-5). Conclusions: This study suggests that eyewitnesses of spells may be better historians of semiologic features than patients themselves. With the availability of electronic communication, it may be useful to contact eyewitnesses for further history in the evaluation of spells.