Aetiological Investigation of Epilepsy in Adults With a Learning Disability – a Community Audit

AIMS: To demonstrate adherence to national standards for the aetiological investigation of epilepsy in Bromley Community Learning Disability Team (CLDT), Oxleas NHS Foundation Trust. The National Institute for Health and Care Excellence (NICE) and International League Against Epilepsy (ILAE) advise strenuous attempts to identify the aetiology of epilepsy as it often carries significant treatment implications. The ILAE divides aetiology into six categories selected because of their potential therapeutic consequences (structural; genetic; infectious; metabolic; immune; unknown). METHODS: Audit standards were derived from NICE and ILAE. The key standard was that 100% of patients should have sufficient aetiological investigation of their epilepsy, including a dysmorphism assessment, neuroimaging, and genomics, as appropriate. The population was defined as all patients open to the Epilepsy Service of Bromley CLDT in December 2021. Data were collected using a secure electronic database between December 2021 and January 2022. RESULTS: 76 patients (52 male, 24 female) were audited, mean age 38 years (range 18-79 years). Learning disability severity included borderline (n=3), mild (n=28), moderate (n=24), severe (n=17) and profound (n=4). Identified aetiologies included structural (42%; n=32), genetic (13%; n=10), and infectious (5%; n=4), with one patient having both genetic and infectious aetiology. Aetiology was unknown in the remaining 41% (n=31) of patients, of which 58% (n=18) had outstanding investigations. In 72% (n=13), there was no apparent reason for investigations to be outstanding. Genomics was the commonest outstanding investigation (70%, n=14), followed by neuroimaging (20%, n=4) and dysmorphism assessment (10%, n=2). In addition, 40% (n=12) of patients were newly eligible for whole genome sequencing – a recent development within 12 months and thus excluded from outstanding investigations. CONCLUSION: This audit demonstrates adherence to national standards is below 100%. Where appropriate, patients with outstanding investigations should be approached. Dissemination of findings and an action plan are required before re-audit.