Primary sleep disorders can cause long-term sleep disturbance in patients with autoimmune mediated limbic encephalitis

ObjectivesAntibody mediated limbic encephalitis causes a sub acute encephalopathy with an amnestic syndrome, seizures and often an affective prodrome. Sleep disturbance including abnormal dream sleep and insomnia are described in a percentage of long-term survivors but there are very few detailed assessments of sleep disturbance in patients beyond the acute phase of illness. The objectives of this study were to understand the causes of sleep disturbance in the long-term survivors of antibody mediated limbic encephalitis.Patients and methodsWe screened twelve patients under long-term follow up with sleep questionnaires and went on to perform detailed sleep studies (polysomnography) in those who reported sleep disturbance.ResultsTwo were found to have persistent, severe central and obstructive sleep apnoea and two others to have restless legs and periodic limb movements of sleep.ConclusionsThis highlights the need to investigate sleep disturbance in this group of patients. Effective treatments may be available to improve quality of life and daytime function.