Characteristics of Non-diagnostic Admissions to the Epilepsy Monitoring Unit
Nimit Desai1, Evangelos Pavlos Myserlis1, Pranav Patel1, Sarah Schmitt1
1Medical University of South Carolina
Objective:
We aim to identify characteristics of non-diagnostic admissions to the Epilepsy Monitoring Unit.
Background:

Admission to an Epilepsy monitoring unit (EMU) is considered the gold standard for characterization of seizures or spells and can help neurologists distinguish between seizures and non-epileptic events. About 15%-27% of all long-term video monitoring studies are non-diagnostic. Non-diagnostic studies after admission to EMU lead to a significant strain on the healthcare system due to added costs and financial and emotional stress to patients due to the uncertainty of diagnosis.

Design/Methods:
We performed a retrospective chart review of patients >18 years of age admitted to the EMU at a Level 4 epilepsy center for event characterization. We analyzed variables including demographic data, length of stay, age of onset, event frequency, anti-seizure medication use, epilepsy risk factors, previous normal routine EEG and MRI findings. Descriptive statistics were expressed as mean (SD) or median (IQR) for continuous variable and count (proportion) for categorical variables, respectively.
Results:

Preliminary analysis of 137 patient charts revealed 39 admissions (28.4%) were non-diagnostic. Of these, 67% were female and 71% were Caucasian. Mean age of presentation was 41.9 (13.46) years and median age of onset was 32 (17.25-43) years. The average length of stay was 3.64 (1.27) days and average event frequency prior to admission was 10.1(19) events/month. Median anti-seizure trials prior to EMU evaluation was 1 (0-2). 62% of patients had a normal preadmission routine EEG.  

Conclusions:

Approximately 30% of admissions to the EMU are non-diagnostic.  Nearly two-thirds of these patients were women, had a normal preadmission routine EEG and majority were of Caucasian descent.  

10.1212/WNL.0000000000206703