Howl: Nightmare or REM Sleep Behavior Disorder?

OBJECTIVE

Nightmare disorder consists of the appearance of unpleasant and vivid, repeated dreams, with a situation of discomfort and anguish on awakening. Its prevalence is 3%-4% in adults. They do not associate muscle mobilization during this phase. REM sleep behavior disorder (RSBD) is a rare parasomnia (0.5% of people older than 60 years of age), characterized by the presence of unpleasant dreams, with violent content, and vigorous movements of limbs (kicks and punches), reflecting a loss of muscle atony typical of the REM phase of sleep. Language (screams and words) can also be emitted. The same clinical manifestations of RSBD can appear in other sleep disorders. The diagnosis requires the performance of a polysomnography.

METHODS

We present the case of a 41-year-old man referred for vivid and unpleasant dreams, beginning in the last year, related to work stress.

RESULTS

The polysomnography showed the loss of atony in the REM phase and emission of a prolonged howl after which the patient continues in the REM phase.

DISCUSSION: Prolonged howling is a very rare symptom in sleep disorders, and very atypical in RSBD, so polysomnography is essential to confirm the diagnosis and rule out other parasomnias.