Adult-Onset Sleepwalking Secondary to Hyperthyroidism: Polygraphic Evidence.

Sleepwalking is a disorder characterized by complex motor behaviors arising from slow wave sleep usually occurring in children. The adult onset of sleepwalking suggests the presence of an external precipitating factor leading to the occurrence of the disorder. Hyperthyroidism has been reported to be the possible cause of sleepwalking in a few cases. We present the case of a 36-year-old man who reported a sudden appearance of nocturnal episodes of sleepwalking. He underwent a complete video polysomnography (VPSG), which showed a polygraphic pattern arising from stage N3 sleep related to the presence of simple motor behaviors. Routine blood tests showed a mild hyperthyroidism. After 4 months of thyrostatic treatment, the patient reported no more sleepwalking events. A VPSG performed at the last follow-up showed the absence of pathological electroclinical events arising from stage N3 sleep. Therefore, we hypothesize that there is a link between sleepwalking and thyroid dysfunction in our patient.