Neurocardiogenic syncope: frequency and consequences of its misdiagnosis as epilepsy.
BACKGROUND
Neurocardiogenic syncope (NCS) can be mistaken as a seizure. We reviewed the frequency and diagnostic consequences of this misdiagnosis.


METHODS
A retrospective review of outpatient adult epilepsy clinic charts (QEII Health Sciences Centre, Halifax, NS) was conducted to identify NCS patients referred with a provisional diagnosis of seizures. Charts were reviewed in detail with an emphasis on the consequences of misdiagnosis.


RESULTS
Of 1506 consecutive referrals to the epilepsy clinic, 194 (12.9%) ultimately had a clinical diagnosis of NCS. Mean age was 38 +/- 16 years (mean age of syncopal onset was 28 +/- 16 years). Two-thirds of referrals were from primary care physicians (including emergency departments) and 18% from neurologists. Thirty-five percent were prescribed antiepileptic drugs (AEDs) prior to referral with eight patients (4.1%) experiencing hypersensitivity reactions. Three of five women had adverse pregnancy outcomes while taking AEDs. One-third of patients had restrictions placed on their driving privileges while 11 patients (5.7%) had their employment interrupted. Diagnostic modalities used in the work-up included EEG (90%), CT head (51%), and MRI head (15%).


CONCLUSIONS
NCS is commonly misdiagnosed as epilepsy. Some patients had an incorrect diagnosis for > 10 years. Patients with this misdiagnosis are often excessively investigated, inappropriately treated, and have unnecessary restrictions placed on driving and employment.
Josephson
Colin B
CB
Neuroelectrodiagnostic Unit, Capital Health Authority, Halifax, NS, Canada.
Rahey
Susan
S
Sadler
R Mark
RM
D000293:Adolescent; D000328:Adult; D000927:Anticonvulsants / Q000627:therapeutic use; D003937:Diagnosis, Differential; D003951:Diagnostic Errors; D004827:Epilepsy / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012017:Referral and Consultation; D012189:Retrospective Studies; D012640:Seizures / Q000175:diagnosis* / Q000209:etiology; D019462:Syncope, Vasovagal / Q000175:diagnosis*
D000927:Anticonvulsants