Sleep and cranial dystonia.

A nocturnal polygraphic study was performed on 10 patients with cranial dystonia (blepharospasm (BS) and oromandibular dystonia (OMD)). All patients showed impaired sleep efficiency and reduced slow and REM sleep, more marked in subjects with severe dystonia. Abnormal muscular activity decreased progressively with deeper sleep and during the first hours of the night, without disappearing. A disordered hypnic++ pattern and impaired motor control even during sleep are typical features in cranial dystonia.