Mind the gap: Multiple events and lengthy delays before presentation with a "first seizure"

Abstract

Objective: Up to half of patients assessed for suspected new-onset epileptic seizures report previous undiagnosed events. This suggests that delay to timely and expert assessment is a major issue. Very little is known about the degree of delay or nature of the undiagnosed events, impacting on our understanding of new-onset epilepsy. In this study we aimed to examine events that occur before presentation, as well as the extent and risk factors for delay to assessment.

Method: Included in this retrospective study were 220 patients diagnosed at the First Seizure Clinic (Austin Health, Australia) between 2003 and 2006 with an epileptic index seizure. Patients with a prior diagnosis of epileptic seizures were excluded. Chart review was undertaken, including detailed interviews conducted by an epileptologist at first assessment. Logistic regression assessed risk factors for delay from first event to presentation, including event characteristics, socioeconomic disadvantage, employment, and distance to medical facility.

Results: Forty-one percent (n = 90) of patients had one or more event before their index seizure. Of these, 50% had multiple or more than five prior events and 28% experienced one or more convulsive event before the index seizure. Of the total 220 patients, 36% had delayed presentation >4 weeks, 21% delayed >6 months, and 14% delayed >2 years. First events without convulsions or features likely to disrupt behaviour were strongly associated with delay (p = <0.001). Relative socioeconomic disadvantage was also associated with delay to presentation (p = 0.04).

Significance: Our findings suggest a gap in early diagnosis and care in a sizable proportion of new-onset cases, despite a "first world" urban environment and the availability of free basic medical care. Delay appears particularly likely when events are nonconvulsive or low-impact, suggesting that these seizure types may be underrepresented in studies of new-onset epilepsy. This has implications for our understanding of the incidence, evolution, impact, and treatment response of new-onset epilepsy.

Keywords: Incidence; New-onset epilepsy; Socioeconomic disadvantage; Treatment-gap.