A parasomnia overlap disorder involving sleepwalking, sleep terrors, and REM sleep behavior disorder in 33 polysomnographically confirmed cases

A series of 33 patients with combined (injurious) sleepwalking, sleep terrors, and rapid eye movement (REM) sleep behavior disorder (viz. 'parasomnia overlap disorder') was gathered over an 8-year period. Patients underwent clinical and polysomnographic evaluations. Mean age was 34 ± 14 (SD) years; mean age of parasomnia onset was 15 ± 16 years (range 1-66); 70% (n = 23) were males. An idiopathic subgroup (n = 22) had a significantly earlier mean age of parasomnia onset (9 ± 7 years) than a symptomatic subgroup (n = 11) (27 ± 23 years, p = 0.002), whose parasomnia began with either of the following: neurologic disorders, n = 6 [congenital Mobius syndrome, narcolepsy, multiple sclerosis, brain tumor (and treatment), brain trauma, indeterminate disorder (exaggerated startle response/atypical cataplexy)]; nocturnal paroxysmal atrial fibrillation, n = 1; posttraumatic stress disorder/major depression, n = 1; chronic ethanol/amphetamine abuse and withdrawal, n = 1; or mixed disorders (schizophrenia, brain trauma, substance abuse), n = 2. The rate of DSM-III-R (Diagnostic and Statistical Manual, 3rd edition, revised) Axis I psychiatric disorders was not elevated; group scores on various psychometric tests were not elevated. Forty-five percent (n = 15) had previously received psychologic or psychiatric therapy for their parasomnia, without benefit. Treatment outcome was available for n = 20 patients; 90% (n = 18) had substantial parasomnia control with bedtime clonazepam (n = 13), alprazolam and/or carbamazepine (n = 4), or self- hypnosis (n = 1). Thus, 'parasomnia overlap disorder' is a treatable condition that emerges in various clinical settings and can be understood within the context of current knowledge on parasomnias and motor control/dyscontrol during sleep.