Epilepsy is a condition that causes patients to have seizures. The condition affects approximately 1% of the population in the United Kingdom. Epilepsy can be controlled by anti-epileptic drugs but for some patients, their epilepsy is intractable meaning they still have seizures despite trying several different types of drug either on their own or taken together. For these patients, other treatment options include surgery to remove the part of the brain that is causing the seizure, or vagus nerve stimulation in which a small electrical device is fitted that can send impulses to the brain to prevent seizures. In this study we wish to select people with intractable epilepsy and group them according to how they are treated, that is by continuing on drugs alone, by undergoing epilepsy surgery or by having a vagus nerve stimulation implant. We then wish to follow these patients to look at how often they are admitted to hospital as inpatients and to accident and emergency.
This is a retrospective, non-interventional study (NIS) based on a secondary use of anonymised, patient level data obtained from primary (CPRD GOLD) and secondary care (HES) databases. The objective of this study is to measure the real-world effectiveness of different treatments, as proxied by healthcare utilisation. Patients with a diagnosis of epilepsy who are defined as intractable based on a minimum 2-day inpatient admission for epilepsy monitoring will be classified by the following treatments modalities: (i) continued anti-epilepsy drug (AED) therapy with no additional treatment; (ii) epilepsy surgery, generally with continued AED therapy; (iii) Vagus Nerve Stimulation therapy adjunctive to AED therapy. The primary analyses will evaluate total inpatient hospitalizations, epilepsy-related inpatient hospitalizations and accident & emergency (A&E) department visits. Duration of inpatient stay, total outpatient services utilisation, drug utilisation and all-cause mortality will be evaluated in secondary analyses. Patient demographics and baseline characteristics will be summarized by treatment group and overall. Outcome incidence rates will be calculated on patient-quarters by treatment group and overall. Mean changes from baseline in incidence rates over time, together with the associated 95% CI, will be derived overtime. Evaluation of the effectiveness of population-level health interventions will be performed by means of the Interrupted Time Series analysis.
Health Outcomes to be Measured:
All inpatient admissions, epilepsy related admission; accident and emergency contacts.
Duration of inpatient stay; all outpatient contacts; neurology all outpatient contacts; psychiatric all outpatient contacts; all outpatient contacts in all other specialities; anti-epilepsy drug prescriptions; epilepsy rescue prescriptions; other prescriptions related to the central nervous system; all other prescriptions; all-cause mortality
HES Accident and Emergency;HES Admitted Patient Care;HES Outpatient;ONS Death Registration Data