Abstract
OBJECTIVE: In the current study, we aimed to assess the diagnostic delay and the impact of diagnostic delay on seizure outcome in a cohort of newly diagnosed patients with focal epilepsy. METHODS: The study material was compiled from eight clinical antiseizure medication monotherapy trials conducted at Kuopio Epilepsy Center during 1995-2016. We analyzed the time from first seizure to diagnosis, the number of seizures before diagnosis, and the response to treatment at five years. RESULTS: Of the 176 patients (age range 15-75 years) in the cohort, 135 (77%) had had more than two seizures before treatment. The majority of these (79 patients, 45%) had had three to ten seizures. Median number of all seizures before diagnosis was 5 (range 2-2000). Focal aware seizures and focal impaired awareness seizures were more frequent than focal to bilateral tonic-clonic seizures; median number 45 (range 2-2000), 11 (range 2-220), and 3 (range 2-30), respectively (P < .001). Median delay was 12 months (range 0-362). Diagnostic delay alone did not correlate with the treatment response at five years. However, an increasing number of seizures before diagnosis indicated a worse seizure outcome (P < .001). SIGNIFICANCE: This study shows that patients with focal epilepsy experience significant delays in diagnosis even in developed countries, especially with seizure types other than tonic-clonic seizures. In these cases, a long delay in diagnosis alone might not affect the long-term outcome. However, when accompanied with recurrent seizures misinterpreted by the patient or healthcare providers, the effect of such delay on prognosis can be considerable.