Comparative Analysis of Seizure Clusters in Patients with and Without a History of Epilepsy Presenting to the Emergency Department

Abstract

Seizure clusters can be observed in patients with epilepsy as well as in individuals without a previous history of epilepsy. However, there are no data on whether seizure clusters differ between these two populations. The purpose of this study was to investigate the clinical presentation, diagnostic findings, presence of seizure triggers, outcomes and complications of seizure clusters in patients with epilepsy and individuals without epilepsy in their medical history. The results indicate that epilepsy history was not independently associated with the number of seizures during cluster; however, increasing age was significantly associated with a lower seizure burden, and pneumonia demonstrated a marginal positive association. Structural brain lesions were prevalent in both groups; particularly chronic post-stroke lesions and frontal lobe lesions were significantly more common among epilepsy patients. Over half of patients without prior epilepsy received a new epilepsy diagnosis following the cluster event. No severe complications, including status epilepticus or postictal psychosis, were observed. Our findings suggest that age, acute comorbidities, and structural brain pathology likely exert greater influence on frequency of seizures during cluster. Chronic post-stroke lesions, which have not yet been reported as a risk factor for seizure clusters, were the most frequent brain pathology in both groups and may thus be considered as an additional risk factor for this clinical entity. Prospective and larger-scale studies are needed to further clarify these associations.

Keywords: cluster; emergency department; epilepsy; risk factor; seizure.

Figure 1

Median number of seizures (IQR): (a) all patients, 3.5 (1); (b) patients with epilepsy, 4 (1.75); (c) patients without epilepsy, 3 (1.5). Mann–Whitney U test, U = 81, Z = 2.37016; p = 0.017.