Diagnostic screening for epilepsy, functional neurological disorder, and other paroxysmal disorders: A clinical
Dominique Eden1, Philippa J Karoly2, Benjamin H Brinkmann1
1Seer Medical, Australia.
Objective:
Seizures, or seizure-like events, can indicate over 50 neurological disorders, and interpretation of patient-reported symptoms is subjective, leading to misdiagnosis. This study aimed to determine diagnostic utility of multi-choice questions to assess seizures in a clinical setting.
Patients & Methods:
This retrospective study of Mayo Clinic neurology patients (2016 - 2021) analysed de-identified Electronic Health Records from adults with a paroxysmal disorder who completed Mayo Clinic's 'Epilepsy Pre-screening Questionnaire'. Diagnostic groups were epilepsy, functional neurological disorder (FND), syncope, and other neurological disorders. The main outcome was group-level separability of survey responses between diagnostic groups (assessed from response proportions using a chi-squared test with Holm-Sidak correction for multiple comparisons).
Results:
4,130 records were included for epilepsy (n = 3,194), FND (n = 214), syncope (n = 101), other (n = 621). Seven multichoice questions provided significant separability between diagnostic groups, with event duration, specific warnings and symptoms providing greatest diagnostic utility. Those with syncope were significantly more likely to report short events, of a few seconds, compared to every other group (syncope: 27 %, other: 11 %, epilepsy: 9 %, FND: 1 %). People with FND were also significantly more likely to report events > 7 min (27 %), compared to those with epilepsy (11 %). Conversely, events lasting < 1 min were still reported by 23 % of people with FND and long seizures (>7 mins) were reported by almost 10 % of people with epilepsy. Pre-seizure warnings were similar for focal and generalised epilepsy, contradicting the assumption that auras are mainly associated with focal epilepsy.
Conclusion:
The results validate the diagnostic utility of general questions about event duration, related symptoms and comorbidities in a meaningfully sampled patient cohort that was representative of people presenting with seizures or seizure-like events presumed to be epilepsy (i.e. not people presenting with an obvious diagnosis of non-epileptic seizures). Findings could inform development of standardised, patient-reported surveys to aid differential diagnosis across common neurological conditions.
