The Man Who Fought in Sleep

A 60-year-old Caucasian man presents to a sleep disorders clinic with a chief complaint of abnormal body movements and talking during sleep. He is accompanied by his wife, who reports that the patient frequently shouts, punches, and kicks during sleep. The episodes began 4 to 5 years ago. Initially, they were sporadic but have been occurring once or twice a week lately, usually in the later part of the night. Three nights ago, the patient punched his wife violently in sleep and then pushed her away while yelling loudly. When she woke him up, he said that he was dreaming that he was in a jungle, fighting a bear. She is now afraid to sleep with him and sleeps in a different bed. The patient feels embarrassed and says that he has frequently experienced dreams in which he fights an animal or a monster. He denies any daytime complaints. The patient has a history of hypertension and hypercholesterolemia. His medications include metoprolol 50 mg twice a day and simvastatin 20 mg once a day. He smoked 1 pack of cigarette a day for 35 years until he quit 8 years ago. He drinks 1 to 2 beers on the weekend but denies alcohol abuse. On examination, the patient is an overweight male. The remainder of the findings on physical examination are normal. The patient undergoes overnight polysomnography. The accompanying figure shows an epoch from the polysomnogram. The sleep technician notes that the patient was kicking and shouting in sleep during this episode. Figure 1 An epoch from the patient's polysomnogram. EOG refers to electrooculogram; EMG, electromyogram; EKG, electrocardiogram. Which of the following is true about this disorder? The dreams are usually associated with abrupt awakenings and a feeling of panic, with full alertness occurring immediately upon awakening. The patient has a higher likelihood of developing multiple system atrophy. The patient has a higher likelihood of having iron-deficiency anemia. Secondary enuresis and tongue-biting are common features. Answer: B Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia characterized by a loss of the normal skeletal muscle atonia during REM phase of sleep. The disorder frequently manifests as enactment of dreams, resulting in shouting, flailing of arms, and moving and kicking during sleep, and may result in injury to self and to others.1 It is common for people affected by this disorder to report a history of vivid, intense, and violent dreams. RBD is predominantly a disease of older men (older than 50 years of age), with the mean age at presentation in 1 series being approximately 64 years.2 The polysomnogram frequently reveals augmented phasic or tonic muscular activity during REM sleep. The accompanying epoch demonstrates increased activity in chin -electromyogram and leg-electromyogram leads during REM stage, along with technician's notation, “talking in sleep.” RBD may be idiopathic in approximately 60% of cases, other cases being associated with neurologic disorders such as ischemic cerebrovascular disease, subarachnoid hemorrhage, Parkinson disease, multiple system atrophy, progressive supranuclear palsy, Shy-Drager syndrome, olivopontocerebellar degeneration, and multiple sclerosis. Many patients with “idiopathic” RBD will develop neurodegenerative disorders many years after the onset of parasomnia (choice B).3 Clonazepam is an effective therapy for most persons with RBD.1 This disorder should be differentiated from nightmares, which can occur at any age and are usually followed by abrupt awakenings accompanied by a sensation of fear or panic (choice A). Iron-deficiency anemia (choice C) is associated with restless leg syndrome and not RBD. Secondary enuresis and tongue biting (choice D) are features of epilepsy as opposed to RBD. Although sleep-related epilepsy would be a consideration in persons with focal limb movements during sleep, the history in this case is typical of RBD.