Diagnostic guideline adherence in patients with a first epileptic seizure

Abstract

Introduction National guidelines recommend repeating an electro-encephalogram (EEG) in patients with suspected epilepsy whose first routine EEG (rEEG) and brain imaging is normal or inconclusive. However, controversy exists regarding the diagnostic value and benefits of various types of additional EEGs leading to a reduction in guideline adherence. A survey found that 50% of Dutch neurologists indicated guideline-adherence. Real world data on adherence and the consequences of non-adherence are lacking.

Methods In this historical cohort study, we evaluated patients who received a rEEG at the St. Antonius hospital in 2018 after a first unprovoked suspected epileptic seizure. We analyzed guideline adherence, final diagnosis at follow-up and seizure recurrence rate while not treated with antiepileptic medication for up to two years in patients who were diagnosed according to the guideline and patients who were not.

Results A total of 463 patients (235 females; mean age 44±25) were included. Diagnostics according to guidelines were performed in 31.1% (144/463) patients. Epilepsy was the most likely diagnosis at follow-up in 11.3% (36/319) patients not diagnosed according to the guideline and in 50.7% (73/144) patients diagnosed according to the guideline (p<0.01). The recurrence rate in patients with epilepsy was higher in the guideline non-adherence group (66.7% (24/36) versus 43.8% (32/73), p:0.03).

Conclusion Guideline adherence was low, but the incidence of epilepsy was also low in patients not diagnosed according to the guideline. Seizure recurrence rates were higher when the guideline was not followed. This supports guideline adherence but also indicates that better selection of patients with a reasonable a-priori risk of epilepsy for whom this guideline applies is needed.