A systematic review of seizure clusters: Prevalence, risk factors, burden of disease and treatment patterns

Seizure clusters (SCs) are episodes of consecutive seizures that occur within a short period. The treatment patterns of rescue medications (RMs), as well as the burden of SCs, have not been assessed. A systematic literature search on Embase.com (in PubMed and Embase), supplemented with keyword-based and bibliographic searches, identified 44 articles for disease burden, three treatment guidelines, and three articles for treatment patterns. Common SC definitions were ≥3 seizures/24 h, ≥2/24 h and ≥2/6 h. The rate of SCs in prospective studies ranged from 21.7 %-42.5 %. The frequency of status epilepticus (SE) was higher in SC patients. SCs were associated with higher seizure frequency, higher risk of treatment resistance, and lower likelihood of seizure remission. Quality of life (QoL) was lower in children with SCs than in those with isolated seizures. Seizure-related hospitalization was more common in SC than non-SC patients. SCs adversely affected the productivity of patients and their caregivers. In outpatients with SCs, RMs were prescribed to 24.6 %-89.6 % and utilized by 15.6 %-44.5 %, with rates being higher in children. Key reasons for RM under-utilization were lack of seizure action plans, poor physician-patient communication, and concerns with administration route. In conclusion, SCs are associated with a higher risk of SE, treatment resistance, and low rate of seizure remission. They adversely affect patient and caregiver QoL and work productivity. However, RMs are under-prescribed, and there is an urgent need to improve recognition of SCs, improve use of seizure action plans, and remove barriers to RM use.