Rapid switching from levetiracetam to brivaracetam in pharmaco-resistant epilepsy in people with and without intellectual disabilities: a naturalistic case control study.

BACKGROUND: Approximately one quarter of people with an intellectual disability (PwID) have epilepsy of whom nearly three-quarters are pharmaco-resistant. There are higher reported neuropsychiatric side-effects to anti-seizure medication (ASM) in this group. Levetiracetam (LEV) is a first-line ASM with a stronger association with neuropsychiatric symptoms for PwID than other ASMs. Brivaracetam (BRV) is a newer ASM. Recent studies suggest a beneficial effect of swapping people who experience neuropsychiatric events with LEV to BRV. However, there is limited evidence of this for PwID. This evaluation analyses real world outcomes of LEV to BRV swap for PwID compared to those without ID. METHODS: We performed a multicentre, retrospective review of clinical records. Demographic, clinical characteristics and reported adverse events of patients switched from LEV to BRV (2016-2020) were recorded at 3 months pre and 6- and 12-month post-BRV initiation. Outcomes were compared between PwID and those without and summarised using cross-tabulations and logistic regression models. A Bonferroni correction was applied. RESULTS: Of 77 participants, 46 had ID and 52% had a past psychiatric illness. 71% participants switched overnight from LEV to BRV. Seizure reduction of > 50% was seen in 40% patients. Psychiatric illness history was predictive of having neuropsychiatric side-effects with LEV but not BRV (p = 0.001). There was no significant difference for any primary outcomes between PwID versus without ID. CONCLUSIONS: Switching from LEV to BRV appears as well tolerated and efficacious in PwID as those without ID with over 90% still on BRV after 12 months.