Clinical and Polysomnographic Characteristics of Narcoleptic Patients with Status Cataplecticus

  Objective  To explore the clinical and polysomnographic characteristics of narcoleptic patients with status cataplecticus.

  Methods  We collected the clinical data of 5 patients with status cataplecticus out of 115 narcoleptic patients admitted to Department of Neurology in Peking Union Medical College Hospital from January 2002 to December 2011. The 5 patients had a mean age of 49.1 years (range, 46-59 years) at diagnosis. Their disease course ranged from 3 to 9 months. All of them underwent physical and neurological examinations, neuroimaging, and multiple sleep latency test (MSLT). Three of them underwent polysomnography (PSG).

  Results  The first symptom was excessive daytime sleepiness in 4 patients, cataplexy in 1 patient. All patients had frequent cataplectic attacks, diagnosed as status cataplecticus. Other symptoms included hypnagogic hallucinations (2/5) and sleep paralysis (3/5). The MSLT showed a mean sleep latency from 0.5 to 2.5 minutes, and 4 patients had more than 2 sleep-onset rapid eye movement period (SOREMP), and 1 patient had 1 SOREMP. PSG showed that a waking electroencephalography (EEG) existed during cataplectic attacks. Electromygraphy showed suppressions of activity. All patients were treated with clomipramine, which completely resolved the attacks.

  Conclusions  Cataplexy in narcoleptic patients showing the recurrent episodes can be diagnosed as status cataplecticus. PSG supports that cataplectic attacks represent dissociated rapid eye movement phenomena in which there is only the somatic component (atonia) without the cerebral one (sleep).