Objective: Genetic variants of the neuronal nicotinic acetylcholine receptor (nAChR) cause autosomal dominant sleep-related hypermotor epilepsy. Approximately 30% of autosomal dominant sleep-related hypermotor epilepsy patients are medically intractable. In preclinical models, pathogenic nAChR variants cause a gain of function mutation with sensitivity to acetylcholine antagonists and agonists. Nicotine modifies the activity of nAChRs and can be used as targeted therapy.
Methods: We reviewed next-generation sequencing epilepsy panels from a single laboratory (GeneDx) from patients at Children's Medical Center Dallas between 2011 and 2015 and identified patients with nAChR variants. Retrospective review of records included variant details, medical history, neuroimaging findings, and treatment history.
Results: Twenty-one patients were identified. Four patients were prescribed nicotine patches for intractable seizures. Three of 4 patients had a clinical response, with >50% seizure reduction.
Conclusions: Treatment with a nicotine patch can be an effective therapy in epilepsy patients with nAChR gene variants. We propose consideration of transdermal nicotine treatment in intractable epilepsy with known nAChR variants as an experimental therapy. Further clinical trials are needed to fully define therapeutic effects.
Keywords: acetylcholine nicotinic receptors; autosomal dominant nocturnal frontal lobe epilepsy; autosomal dominant sleep-related hypermotor epilepsy; genetic; nicotine.