Confusional Arousals Research Articles

Parasomnias

Parasomnias have long been recognized as part of sleep-related disorders or diseases in the mental disorders classification system such as Diagnostic and Statistical Manual of Mental Disorders. Nevertheless, many parasomnia symptoms are considered as a transient deviation from the norm in otherwise normal subjects due to disrupted status of consciousness. Sleep states are classified as rapid eye movement (REM) sleep and non-REM (NREM) sleep; similarly, parasomnias are classified as NREM-related parasomnias and REM-related parasomnias. NREM-related parasomnias share common pathophysiology of arousal-related phenomenon out of slow-wave sleep. Although listed as REM parasomnia disorders, nightmares and sleep paralysis are still considered comorbid symptoms or signs of other sleep disorders or mental disorders. Only REM sleep behavior disorder (RBD) is considered a relatively homogenous disease entity among all parasomnia diagnoses. Although RBD is the most newly added disorder entity in parasomnias, it is the most rigorously studied parasomnia such as RBD is strongly and clearly associated with concomitant or future developing neurodegenerative disease. This review contains 1 figure, 4 tables, and 18 references. Key Words: confusional arousals, dream enactment, pseudo-RBD, REM sleep behavior disorder, sleep-related eating, sleep terror, sleepwalking

Video polysomnographic findings in non-rapid eye movement parasomnia.

Although video polysomnography (vPSG) is not routinely recommended for the evaluation of typical cases of non‐rapid eye movement (NREM) parasomnias, it can aid diagnosis of unusual cases, other sleep disorders and complicated cases with REM behaviour disorder (RBD), and in differentiating parasomnias from epilepsy. In this study, we aimed to assess vPSG findings in consecutive patients with a clinical diagnosis of NREM‐parasomnia covering the whole phenotypic spectrum. Five hundred and twelve patients with a final diagnosis of NREM parasomnia who had undergone vPSG were retrospectively identified. vPSGs were analysed for features of NREM parasomnia and for the presence of other sleep disorders. Two hundred and six (40.0%) patients were clinically diagnosed with sleepwalking, 72 (14.1%) with sleep terrors, 39 (7.6%) with confusional arousals, 15 (2.9%) with sexsomnia, seven (1.4%) with sleep‐related eating disorder, 122 (23.8%) with mixed phenotype, and 51 (10.0%) with parasomnia overlap disorder (POD). The vPSG supported the diagnosis of NREM parasomnia in 64.4% of the patients and of POD in 98%. In 28.9% of the patients, obstructive sleep apnea (OSA) or/and periodic limb movements during sleep (PLMS) were identified, most commonly in older, male, sleepy and obese patients. vPSG has a high diagnostic yield in patients with NREM parasomnia and should be routinely performed when there is diagnostic doubt, or in patients where there is a suspicion of OSA and PLMS.

Parasomnia versus epilepsy: An affair of the heart?

Differential diagnosis between sleep-related epileptic seizures and NREM parasomnia remains challenging. Pathophysiological markers to differentiate both conditions are needed. Activation of autonomic system is present in arousal reactions and epileptic seizures. Our study investigated whether cardiac reactivity differed between arousal disorders and sleep-related seizures. Nocturnal recordings of 50 patients (10 in each group: frontal lobe epilepsy [FLE], temporal lobe epilepsy [TLE], nocturnal terror [NT], confusional arousal [CA], normal arousals [NA]) were retrospectively selected. Timing of the first motor sign and description of behaviours were assessed. Beat-to-beat RR intervals (RRI) as well as heart rate variability were analysed over a period of 60 heartbeats before and after first motor manifestation. The slope and area under the curve (AUC) of RRI were calculated. A significant decrease in RRI was observed at the onset of all events. Statistical analysis revealed: lower RRI in TLE than in other groups; higher slope of RRI in FLE than in NA and TLE, and higher AUC in NT and FLE than in TLE, and in NT than in NA. Sleep stage, episode duration, vocalization characteristics, lateralized or abnormal posture, exploratory behaviour differed between epileptic and parasomnia groups. Analysis of cardiac reactivity seems to be a useful objective tool, together with clinical features, for diagnosing abnormal behaviour during sleep. Cardiac reactivity in TLE could reflect epileptic discharge propagation to brain areas involved in autonomic control, while FLE and NT might involve a strong non-specific activation of the sympathetic system.

The Co-Occurrence of Sexsomnia, Sleep Bruxism and Other Sleep Disorders.

Background: Sleep sex also known as sexsomnia or somnambulistic sexual behavior is proposed to be classified as NREM (non-rapid eye movement) parasomnia (as a clinical subtype of disorders of arousal from NREM sleep—primarily confusional arousals or less commonly sleepwalking), but it has also been described in relation to REM (rapid eye movement) parasomnias. Methods: The authors searched the PubMed database to identify relevant publications and present the co-occurrence of sexsomnia and other sleep disorders as a non-systematic review with case series. Results: In the available literature the comorbidity of sexsomnia and other sleep disorders were reported mainly in case reports and less in case series. Sexsomnia was reported both with one and with multiple sleep-related disorders, with NREM parasomnias and obstructive sleep apnea (OSA) being the most commonly reported. Furthermore, the authors enrich the article with new findings concerning two novel cases of sleep bruxism triggering recurrent sexsomnia episodes. Conclusions: Sexsomnia has still not been reported in the literature as often as other parasomnias. The coexistence of sexsomnia and other sleep-related disorders should be more thoroughly examined. This could help both in sexsomnia as well as other sleep-related disorders management.

Confusional arousals during non-rapid eye movement sleep: evidence from intracerebral recordings.

Confusional arousals (CA) are characterized by the association of behavioral awakening with persistent slow-wave electroencephalographic (EEG) activity during non-rapid eye movement (NREM) sleep-suggesting that sensorimotor areas are "awake" while non-sensorimotor areas are still "asleep." In the present work, we aimed to study the precise temporo-spatial dynamics of EEG changes in cortical areas during CA using intracerebral recordings. Nineteen episodes of CA were selected in five drug-resistant epileptic patients suffering incidentally from arousal disorders. Spectral power of EEG signal recorded in 30 non-lesioned, non-epileptogenic cortical areas and thalamus was compared between CA and baseline slow-wave sleep. Clear sequential modifications in EEG activity were observed in almost all studied areas. In the last few seconds before behavior onset, an increase in delta activity occurred predominantly in frontal regions. Behavioral arousal was associated with an increase of signal power in the whole studied frequency band in the frontal lobes, cingulate cortex, insular cortex, and precuneus. Afterwards, a diffuse cessation of very low frequencies (<1 Hz) occurred. Simultaneously, a hypersynchronous delta activity (HSDA) (1-1.5 Hz) arose in a broad network involving medial and lateral frontoparietal cortices, whereas higher frequency activities increased in sensorimotor, orbitofrontal, and temporal lateral cortices. This HSDA was predominantly observed in the inferior frontal gyrus. During CA, the level of activity changed in almost all the studied areas. The embedding of a broad frontoparietal network, especially the inferior frontal gyrus, in an HSDA might explain the participants' altered state of consciousness.

NREM sleep parasomnias as disorders of sleep-state dissociation.

Non-rapid eye movement (NREM) sleep parasomnias (or NREM parasomnias) are fascinating disorders with mysterious neurobiological substrates. These conditions are common and often severe, with social, personal and forensic implications. The NREM parasomnias include sleepwalking, sleep terrors and confusional arousals - collectively termed disorders of arousal (DOAs) - as well as less well-known entities such as sleep-related sexual behaviours and eating disorders. Affected patients can exhibit waking behaviours arising abruptly out of NREM sleep. Although the individual remains largely unresponsive to the external environment, their EEG shows both typical sleep-like and wake-like features, and they occasionally report dreaming afterwards. Therefore, these disorders offer a unique natural model to explore the abnormal coexistence of local sleep and wake brain activity and the dissociation between behaviour and various aspects of consciousness. In this article, we critically review major findings and updates on DOAs, focusing on neurophysiological studies, and offer an overview of new clinical frontiers and promising future research areas. We advocate a joint effort to inform clinicians and the general public about the management and follow-up of these conditions. We also strongly encourage collaborative multicentre studies to add more objective polysomnographic criteria to the current official diagnostic definitions and to develop clinical practice guidelines, multidisciplinary research approaches and evidence-based medical care.

Demographic, Clinical and Polysomnographic Characteristics of Childhood- and Adult-Onset Sleepwalking in Adults

Background: Sleepwalking (SW) is found to affect children predominantly, but it can persist or appear de novo even among adults. In this study, we assessed the demographic, clinical and polysomnographic profile, trigger factors and associated comorbidities of adult-onset (AO-SW) and childhood-onset (CO-SW) adult sleepwalkers. Methods: In adult sleepwalkers, a structured clinical interview, a battery of questionnaires, video-polysomnography (v-PSG) and standard electroencephalography (EEG) were performed. Results: Among 63 sleepwalkers, 45% had ≥1 episodes/month, 54% had partial recall of the episodes and 36% reported trigger factors for SW. Almost all subjects reported co-occurring parasomnias. In v-PSG, 4% exhibited episodes of SW, 17% confusional arousals, 21% had an increased apnea-hypopnea-index and 6% exhibited features of an overlap parasomnia disorder. In our cohort, 73% reported CO-SW and 27% AO-SW. In subjects with AO-SW, positive family history for parasomnias was found in 33% (vs. 49% in CO-SW), neurological comorbidities in 44% (vs. 14%), psychiatric comorbidities in 25% (vs. 33%), EEG abnormalities in 50% (vs. 29%). Violence during SW episodes was more frequent in males and in subjects with CO-SW (45% for self-injury and 44% for violent behaviour vs. 33 and 29% respectively in the AO-SW group). Conclusions: Adult SW represents a complex and potentially dangerous condition. The characteristics of AO-SW often differ from those of CO-SW.

Non-Rapid Eye Movement Arousal Parasomnias in Children.

Parasomnia is a common pediatric sleep disorder that can cause parents or caregivers distress when experienced by their children. Based on the International Classification of Sleep Disorders, parasomnias can be divided into two subgroups: non-rapid eye movement (NREM) parasomnias and rapid eye movement (REM) parasomnias. REM sleep parasomnias include nightmares, REM behavior disorder, and sleep paralysis, whereas NREM sleep parasomnias include disorders of arousal such as confusional arousals, sleepwalking, sleep talking, night terrors, and sleep-related eating disorder. This review focuses on the epidemiology, clinical presentation, diagnosis, and treatment of the most common form of parasomnias-NREM arousal parasomnias. Additionally, this review aims to help clinicians distinguish NREM parasomnias from nocturnal frontal lobe seizures, as this distinction is important to avoid diagnostic delays and inappropriate medication exposure. [Pediatr Ann. 2017;46(9):e327-e331.].

Non-Rapid Eye Movement Sleep and Overlap Parasomnias.

This article reviews the spectrum of non-rapid eye movement (non-REM) sleep parasomnias, including sleepwalking, confusional arousals, and sleep terrors, which represent the range of phenotypic disorders of arousal from non-REM sleep that occurs in children and adults. The International Classification of Sleep Disorders, Third Edition (ICSD-3) classifies parasomnias according to the sleep stage they emerge from: REM, non-REM, or other. Demographics, clinical features, and diagnosis of non-REM parasomnias are reviewed in this article, and an up-to-date synopsis of guidelines for management strategies to assist in the treatment of these sleep disorders is provided. The non-REM parasomnias are most common in children and adolescents but may persist into adulthood. They can be distinguishable from REM parasomnias and nocturnal epilepsies, and, importantly, may lead to injury. Additionally, other parasomnias in this spectrum include sleep-related eating disorder and sexsomnia. Overlap parasomnia disorder includes one or more manifestations of a non-REM parasomnia seen in combination with REM sleep behavior disorder, representing an apparent erosion of the normally distinct stages of non-REM and REM sleep. A similar yet much more extreme dissociation of states underlies agrypnia excitata and status dissociatus, which represent rare, severe dissociations between non-REM, REM, and wake states resulting clinically in oneiric behaviors and severe derangement of normal polysomnographic wake and sleep stage characteristics. Management of non-REM and overlap parasomnias and state dissociation disorders include ensuring bedroom safety and prescription of clonazepam or hypnosis, in select cases, although in children and adolescents with noninjurious behaviors, non-REM parasomnias are often age-limited developmental disorders, which may ultimately remit by adulthood, and, in these cases, counseling and education alone may suffice. Timely and accurate recognition of the non-REM and overlap parasomnias is crucial to limiting potential patient injury.

Sleep-Wake Disorders of Childhood.

Sleep-wake disorders occur in 10% to 28% of children and differ somewhat in pathophysiology and management from sleep-wake disorders in adults. This article discusses the diagnosis and management of key childhood sleep disorders. The role of sleep in memory consolidation and in the facilitation of learning has been increasingly recognized, even at the toddler stage. Cataplexy, a key feature of narcolepsy type 1, may be subtle in childhood and characterized by transient muscle weakness isolated to the face. Children with obstructive sleep apnea and restless legs syndrome display prominent neurobehavioral symptoms such as daytime inattentiveness and hyperactivity, so it is important to elicit a sleep history when these symptoms are encountered. Systemic iron deficiency occurs in about two-thirds of children with restless legs syndrome and is easily treatable. Parasomnias arising out of non-rapid eye movement (REM) sleep, such as confusional arousals and sleepwalking, may be difficult to distinguish from nocturnal seizures, and, in many cases, video-EEG polysomnography is required to differentiate between causes. Clinicians should routinely integrate the assessment of sleep-wake function into their practices of neurology and child neurology because of the opportunity to improve the quality of life of their patients.

Arousal in Nocturnal Consciousness: How Dream- and Sleep-Experiences May Inform Us of Poor Sleep Quality, Stress, and Psychopathology.

The term “sleep experiences,” coined by Watson (2001), denotes an array of unusual nocturnal consciousness phenomena; for example, nightmares, vivid or recurrent dreams, hypnagogic hallucinations, dreams of falling or flying, confusional arousals, and lucid dreams. Excluding the latter, these experiences reflect a single factor of atypical oneiric cognitions (“general sleep experiences”). The current study is an opinionated mini-review on the associations of this factor—measured with the Iowa sleep experiences survey (ISES, Watson, 2001)—with psychopathological symptoms and stress. Findings support a strong relation between psychological distress and general sleep experiences. It is suggested that that they should be viewed as a sleep disturbance; they seem to represent involuntary intrusions of wakefulness into sleep, resulting in aroused sleep. These intrusions may stem from excessively thin boundaries between consciousness states (e.g., “transliminality”), or, conversely, they may follow an attempt at disconnecting mental elements (e.g., dissociation), which paradoxically results in a “rebound effect.” The extent to which unusual dreaming is experienced as intrusive, rather than controlled, may explain why general sleep experiences are related to psychopathology, whereas lucid dreams are related to psychological resilience. In conclusion, the exploration of the interplay between psychopathology and sleep should be expanded from focusing almost exclusively on quantitative aspects (e.g., sleep efficiency, latency) to including qualitative conscious experiences which may reflect poor sleep quality. Taking into account nocturnal consciousness—including unusual dreaming and permeable sleep-wake boundaries—may unveil rich information on night-time emotional states and broaden our definition of poor sleep quality.

Parasomnia Overlap Disorder with Sexual Behaviors during Sleep in a Patient with Obstructive Sleep Apnea

Sleep-related abnormal sexual behaviors (sexsomnia) are classified as a subtype of NREM sleep parasomnias. Sexsomnia has been reported as part of parasomnia overlap disorder (POD) in two other patients. We present the case of a 42-year-old male patient with video-polysomnography (vPSG) documented POD. The patient had sleepwalking, sleep-related eating, confusional arousals, sexsomnia, sleeptalking, and REM sleep behavior disorder (RBD). Confusional arousals and RBD were documented during the vPSG. This case had the added complexity of obstructive sleep apnea (OSA) playing a role in sleepwalking and sleep related eating, with good response to nasal continuous positive airway pressure (nCPAP). The sexsomnia did not respond to nCPAP but responded substantially to bedtime clonazepam therapy.

Behavioral Treatments for Non-Rapid Eye Movement Parasomnias in Children

Non-rapid eye movement (NREM) parasomnias are common in childhood and include a range of clinical presentations including confusional arousals, sleepwalking, sleep terrors, and sleep-related eating disorder. While parasomnia episodes can be dramatic and elicit concern from parents, parasomnias are predominantly benign and self-limited. A comprehensive clinical evaluation is necessary for appropriate diagnosis and ruling out underlying medical disorders. For youth with parasomnia episodes that are infrequent or limited in severity, standard treatment recommendations, including safety measures and minimizing triggering factors, are highlighted. Scheduled awakening is an evidence-based behavioral treatment that can be effective at decreasing or resolving frequent and severe NREM parasomnias but may be burdensome for parents to implement.

Behavioral Interventions for Parasomnias

Parasomnias are phenomena which may arise from NREM sleep (confusional arousals, sleep terrors, and sleepwalking) or REM sleep (nightmares). All are more common in children. While generally benign and outgrown with age, they may come to clinical attention when sufficiently disruptive to the patient or the patient’s family and in some cases may pose significant safety concerns. In addition to proper preventative measures, behavioral techniques—such as alteration of sleep timings, implementation of scheduled awakenings, and psychotherapy—are important tools in the clinician’s armamentarium. Research into the effectiveness of these interventions primarily consists of case series. However, particularly in the treatment of nightmare disorder, several randomized controlled studies also support their use and in fact suggest they may equally if not more effective as pharmacotherapy for treatment of these common sleep disorders.

Disorders of Arousal

Sleepwalking, sleep terrors, and confusional arousals are non-REM sleep parasomnias grouped under the specific category of disorders of arousal (DOA). These conditions are characterized by incomplete arousals from deep sleep that lead to a broad variety of emotional and motor behaviors. The advent of electroencephalography (EEG) and the discovery of rapid eye movement (REM) sleep as opposed to non-REM sleep allowed researchers to consider these phenomena from a neurophysiological rather than a purely psychopathological perspective. The utilization of new neurophysiologic techniques such as high-density scalp EEG, stereo-EEG, and advanced signal analysis methods shed further light on the mechanisms underpinning DOA and supported the notion that they should be viewed within the frame of the so-called dissociate state of being as intermediate state between wake and NREM sleep. Furthermore, other important issues like the boundaries between motor-behavioral manifestations in DOA and NFLE, neurocognitive functions, the occurrence of mentation/dream imagery during episodes in DOA and DOA daytime consequences, and treatment are still matters of debate.

Not Only Sleepwalking But NREM Parasomnia Irrespective of the Type Is Associated with HLA DQB1*05:01.

Despite the high prevalence and clinical relevance of NREM parasomnias, data on supportive genetic markers are scarce, and mainly refer to sleepwalking only. We retrospectively analyzed clinical, polysomnographic, and HLA findings of 74 adults (37 men) with NREM parasomnia gathered from four neurological sleep centers. Parasomniac events were classified according to ICSD-2 criteria. HLA DQB1 genotyping was compared to regional-matched reference allele-frequencies. Fifty-six patients had more than 2 different parasomnia type: 11 sleepwalking, 4 sleep terrors, 3 confusional arousals only. Parasomniac events were documented during video-polysomnography (V-PSG) in 70% (49/70) of subjects (71.4% confusional arousals, 8.2% sleep terrors, 4.1% sleepwalking, 16.3% ≥ 2 NREM parasomnia types). Violent behavior during V-PSG occurred in 8.5% (6/71). NREM parasomnia onset was reported after the age of 30 years in 6.8% (5/74). The HLA DQB1*05:01 allele was present in 41% (29/71) compared to 24.2% in the regional-matched reference allele group (p < 0.05). This haplotype prevalence did not differ within the NREM parasomnia type. Epworth Sleepiness Score was 10 or higher in 28.6%. This is a large polysomnography-based case series of patients with NREM parasomnia. In patients with suspected sleepwalking or sleep terrors, polysomnography is highly useful in detecting arousals from NREM sleep as a marker of NREM parasomnia. We confirmed previous findings by demonstrating a high prevalence of the HLA DQB1*05:01 genotype for different types of NREM parasomnias. Our findings therefore support a common genetic background, and corroborate the importance of video-polysomnography in the work-up of parasomnia.

Forensic Implications of Sleep-Associated Behavior Disorders

Parasomnias represent a category of disorders that involve complex behaviors or emotional experiences, arising from or occurring during sleep, which might be also associated with (incomplete) awakening. These phenomena are classified as REM- or Non-REM-parasomnias. In particular the latter, including confusional arousal, sleepwalking and sleep terrors but also REM-sleep behavior disorder might result in criminal consequences. Using polysomnography, the pathophysiological mechanisms of these disorders have been investigated thoroughly. Nevertheless, in German literature, forensic implications of complex behaviors arising from sleep disorders have only been described insufficiently. Here we describe the most relevant parasomnias and also how to proceed in the context of forensic assessments.

Update on Sexsomnia, Sleep Related Sexual Seizures, and Forensic Implications

The first classification of sleep-related disorders and abnormal sexual behaviors and experiences was published in 2007. Parasomnias (abnormal sleep-related behaviors and experiences) and sleep-related epileptic seizures were the most frequently reported disorders, apart from Kleine-Levin syndrome (periodic hypersomnia with abnormal wakeful sexual behaviors). The first set of conditions were named sexsomnia (sleepsex) and epileptic (ictal) sexsomnia, respectively. Sexsomnia usually emerges during confusional arousals (CAs) from delta non-REM sleep (N3 sleep), either associated or unassociated with obstructive sleep apnea (OSA). We now report an additional 16 cases of sexsomnia and 2 cases of ictal sexsomnia (temporal lobe epilepsy; bupropion-induced seizures) published from 2007-2014, based on a literature search in PubMed and Embase. The demographics of the second group of 16 sexsomnia cases were similar to those of the first group of 31 cases, in regards to male gender predominance (75% vs. 81%); age at presentation (39 yrs vs. 32 yrs); age of onset (33 yrs vs. 26 yrs); and duration of sexsomnia in males (5.6 yrs vs. 8.3 yrs). The female groups were too small to compare. The distribution of sexual behaviors across the groups was generally comparable in regards to sexual vocalizations, masturbation, fondling, and intercourse/attempted intercourse. Amnesia for the sexsomnia by the affected person was 100% in both groups. Video-polysomnographic studies were conducted in nearly all patients in both groups, and provided important diagnostic findings in almost all patients. The mean number of parasomnias per patient was 1.9+1.4 vs. 2.2+1.0, respectively, with the range extending up to 5 parasomnias per patient. In both groups, a non-REM sleep parasomnia (disorder of arousal [DOA]) was the main cause of the sexsomnia (75% vs. 90%), including a comparable percentage in each group having obstructive sleep apnea (OSA) as the presumed trigger for a DOA with sexsomnia (18.7% vs. 12.9%), which was strongly supported by the control of both sexsomnia and OSA with therapy of OSA with nasal CPAP in 100% (4/4) of treated cases. Overall treatment efficacy was very high in the combined groups (82% [18/22]). Eight novel findings on sexsomnia and ictal sexsomnia were identified. The forensic implications of sexsomnia are discussed.

Distinctive features of NREM parasomnia behaviors in parkinson's disease and multiple system atrophy.

ObjectiveTo characterize parasomnia behaviors on arousal from NREM sleep in Parkinson’s Disease (PD) and Multiple System Atrophy (MSA).MethodsFrom 30 patients with PD, Dementia with Lewy Bodies/Dementia associated with PD, or MSA undergoing nocturnal video-polysomnography for presumed dream enactment behavior, we were able to select 2 PD and 2 MSA patients featuring NREM Parasomnia Behviors (NPBs). We identified episodes during which the subjects seemed to enact dreams or presumed dream-like mentation (NPB arousals) versus episodes with physiological movements (no-NPB arousals). A time-frequency analysis (Morlet Wavelet Transform) of the scalp EEG signals around each NPB and no- NPB arousal onset was performed, and the amplitudes of the spectral frequencies were compared between NPB and no-NPB arousals.Results19 NPBs were identified, 12 of which consisting of ‘elementary’ NPBs while 7 resembling confusional arousals. With quantitative EEG analysis, we found an amplitude reduction in the 5-6 Hz band 40 seconds before NPBs arousal as compared to no-NPB arousals at F4 and C4 derivations (p<0.01).ConclusionsMany PD and MSA patients feature various NREM sleep-related behaviors, with clinical and electrophysiological differences and similarities with arousal parasomnias in the general population.SignificanceThis study help bring to attention an overlooked phenomenon in neurodegenerative diseases.

Are confusional arousals pathological?

The objective of this study was to determine the extent that confusional arousals (CAs) are associated with mental disorders and psychotropic medications. Cross-sectional study conducted with a representative sample of 19,136 noninstitutionalized individuals of the US general population aged 18 years or older. The study was performed using the Sleep-EVAL expert system and investigated sleeping habits; health; and sleep, mental, and medical conditions (DSM-IV-TR, ICSD-II, ICD-10). A total of 15.2% (95% confidence interval 14.6%-15.8%) (n=2,421) of the sample reported episodes of CAs in the previous year; 8.6% had complete or partial amnesia of the episodes and 14.8% had CAs and nocturnal wandering episodes. Eighty-four percent of CAs were associated with sleep/mental disorders or psychotropic drugs. Sleep disorders were present for 70.8% of CAs. Individuals with a circadian rhythm sleep disorder or a long sleep duration (≥9 hours) were at higher risk of CAs. Mental disorders were observed in 37.4% of CAs. The highest odds were observed in individuals with bipolar disorders or panic disorder. Use of psychotropic medication was reported by 31.3% of CAs: mainly antidepressant medications. After eliminating possible causes and associated conditions, only 0.9% of the sample had CA disorder. CAs are highly prevalent in the general population. They are often reported allegedly as a consequence of the treatment of sleep disorders. For the majority of subjects experiencing CAs, no medications were used, but among those who were using medications, antidepressants were most common. Sleep and/or mental disorders were important factors for CAs independent of the use of any medication.