Sleep-Related Rhythmic Movement Disorder and Obstructive Sleep Apnea in Five Adult Patients

Sleep-related rhythmic movements (SRRMs) are typical in infancy and childhood, where they usually occur at the wake-to-sleep transition. However, they have rarely been observed in adults, where they can be idiopathic or associated with other sleep disorders including sleep apnea. We report a case series of 5 adults with sleep-related rhythmic movement disorder, 4 of whom had a previous history of SRRMs in childhood. SRRMs mostly occurred in consolidated sleep, in association with pathological respiratory events, predominantly longer ones, especially during stage R sleep, and recovered in 1 patient with continuous positive airway pressure therapy. We hypothesize that sleep apneas may act as a trigger of rhythmic motor events through a respiratory-related arousal mechanism in genetically predisposed subjects.