Clinical Features and Pathophysiology of Disorders of Arousal in Adults: A Window Into the Sleeping Brain

Introduction: Disorders of Arousal (DoA) are NREM parasomnias that have been typically regarded as self-limited childhood manifestations. It is now clear that DoA can persist in adults, often presenting with distinctive characteristics. So far, few studies have described the clinical course and characteristics of DoA in adulthood, therefore a large part of their semiology is ignored. The aim of this study is to describe the clinical manifestations of DoA in an adult population and to provide a pathophysiological interpretation of their features.Methods: We screened our database for all 1,600 adult (≥15 years) patients with sleep-related motor behaviors between 1995 and 2016. We identified 45 patients with typical DoA episodes, of whom a complete history, neurological examination and diagnostic video-polysomnography (VPSG) were available. All patients provided a detailed description of their episodes (with particular regards to semiology, frequency, and association with stressful life events) in different life periods. VPSG recordings were reviewed and DoA episodes were identified and assigned to three different categories according to their complexity.Results: Our population was composed of 45 adult patients ranging between 15 and 76 years. Sleepwalking was reported by 86% of patients, possibly associated with complex interactions with the environment and violent behaviors in 53% of cases; distressing mental contents were reported by 64%. Recall of the episodes was reported in 77% of patients. Non-restorative sleep was reported in 46% of patients. Stress was a potential episode trigger in 80% of patients. VPSG recordings documented 334 DoA episodes. According to our classification of motor patterns, 282 episodes (84%) were Simple Arousal Movements (SAMs), 34 (10%) Rapid Arousal Movements (RAMs) and 18 (5%) Complex Arousal Movements (CAMs).Discussion: Our study confirms that DoA in adulthood present with distinctive characteristics, such as non-restorative sleep, violence and complex, or bizarre behaviors. Alternative classifications of DoA based on motor patterns could be useful to characterize DoA episodes in adults, as different motor patterns often coexist in the same individual and minor episodes are more common but generally underreported by patients. Prospective studies are needed for a definitive characterization of DoA in adulthood throughout the life course

Specific motor patterns of arousal disorders in adults: A video-polysomnographic analysis of 184 episodes

Objective: To compile an objective accurate description of the motor patterns of adult arousal disorders (ADs). Methods: We reviewed 59 nocturnal video-polysomnographic (VPSG) recordings of 30 adult patients (>15 years) with a history of sleepwalking (SW). We scrutinized the semeiology of all 184 episodes recorded, classifying them into three groups according to three semeiological motor patterns characterized by increasing intensity and complexity: simple arousal movements (pattern I), characterized by head flexion/extension, head flexion/extension and limb movement or head flexion/extension and partial trunk flexion/extension; rising arousal movements (pattern II), characterized by a complete trunk flexion with patient sitting up in bed; and complex arousal with ambulatory movements (pattern III) characterized by SW. The VPSG recordings were compared to those of 10 healthy controls. Results: AD patients presented with 169 pattern I, 37 pattern II, and nine pattern III episodes. Pattern I developed into pattern II in 17 cases and into pattern II followed by pattern III in five patients. Pattern II developed into pattern III in four patients. Onset was abrupt in 55% of the episodes. Episodes lasted a mean (\uc2\ub1standard deviation) of 33 \uc2\ub1 35 s. Movements tended to halt temporarily during 72% of the episodes. We recorded 248 movements during sleep in the healthy controls, none of whom presented with AD patterns. Conclusion: We identified three specific motor patterns in AD patients not previously reported and not observed in healthy controls. Identification of these patterns could be important for diagnosis and serve as the basis for a new definition of AD in adults