Sleep paralysis in African Americans with panic disorder

Prevalence and Clinical Characteristics of Sleeping Paralysis: A Systematic Review and Meta-Analysis

Sleep paralysis (SP) is a mixed state of consciousness and sleep, combining features of rapid eye movement (REM) sleep with those of wakefulness. The exact cause of SP is unknown, and its prevalence varies among the studies. We aim to identify SP's global prevalence, the affected population's characteristics, and the SP's clinical picture. We searched three databases (PubMed, Scopus, and Web of Science (WoS)) using a unique search strategy to identify eligible studies. All observational studies identifying the prevalence or frequency of sleeping paralysis were included. No exclusions are made based on country, race, or questionnaire. The analysis was performed using the latest version of R software (R Core Team, Vienna, Austria). The analysis included 76 studies from 25 countries with 167,133 participants. The global prevalence of SP was 30% (95% CI (22%, 39%)). There were similar frequencies of isolated SP and SP (33%, 95% CI (26%, 42%), I2 = 97%, P <0.01; 31%, 95% CI (21%, 43%), I2 = 100%, P = 0, respectively). A subgroup analysis showed that the majority of those who experienced SP were psychiatric patients (35%, 95% CI (20%, 55%), I2 = 96%, P <0.01). The prevalence among non-psychiatric patients was among students (34%, 95% CI (23%, 47%), I2 = 100%, P = 0). Auditory and visual hallucinations were reported in 24.25% of patients. Around 4% had only visual hallucinations. Meta-regression showed no association between the frequency of SP and sex. Publication bias was detected among the included studies through visual inspection of funnel plot asymmetry. Our findings revealed that 30% of the population suffered from SP, especially psychiatric patients and students. The majority of SP cases lacked associated hallucinations, while a noteworthy proportion experienced combined visual and auditory hallucinations.

Beliefs about sleep paralysis in Turkey: Karabasan attack

The present study examined explanations of sleep paralysis (SP) in Turkey. The participants were 59 college students recruited in İstanbul, Turkey, who had experienced SP at least once in their lifetime. Participants were administered the Sleep Paralysis Experiences and Phenomenology Questionnaire (SP-EPQ) in an interview. When asked whether they had heard of a name for SP, the vast majority (88%) mentioned the "Karabasan"-a spirit-like creature rooted in Turkish folk tradition. Seventeen percent of the participants believed that their SP might have been caused by this supernatural creature. Thirty-seven percent of participants applied various supernatural and religious methods to prevent future SP attacks such as dua (supplicating to God), reciting the Quran, and wearing a musqa (a type of talisman inscribed with Quranic verses). Case studies are presented to illustrate these findings. The Karabasan constitutes a culturally specific, supernatural interpretation of the phenomenology of SP in Turkey.

Sleep paralysis in Italy: Frequency, hallucinatory experiences, and other features

Previous research has found supernatural beliefs about sleep paralysis (SP) to be very prevalent in Italy, with over one third of SP sufferers believing that their SP might have been caused by a supernatural creature known locally as the Pandafeche. The current study further examined features of SP in Italy. All participants had experienced SP at least once in their lifetime. Participants were recruited from the general population (N =  67) in the region of Abruzzo. The Sleep Paralysis Experiences and Phenomenology Questionnaire (SP-EPQ) was orally administered to participants. As hypothesized, we found that Italians from the general population reported high lifetime rates of SP, prolonged duration of immobility during the event, and great fear of the experience (with as many as 42% of SP sufferers fearing that they could die from the experience), all of which were particularly elevated as compared to cultures where there are no such elaborate traditions of SP (e.g., Denmark). In addition, 78% of participants experienced some type of hallucination during their SP. The results we present here suggest that cultural beliefs about SP in Italy (e.g., as being caused by the Pandafeche, as reported elsewhere) potentially can profoundly shape certain aspects of the experience - a type of mind-body interaction.

Sleepwalking and Sleep Paralysis: Prevalence in Colombian Families With Genetic Generalized Epilepsy

BACKGROUND

Sleep deprivation commonly increases seizure frequency in patients with genetic generalized epilepsy, though it is unknown whether there is an increased prevalence of sleepwalking or sleep paralysis in genetic generalized epilepsy patients. Establishing this could provide insights into the bio-mechanisms or genetic architecture of both disorders. The aim of this study was to determine the prevalence of sleepwalking and sleep paralysis in a cohort of patients with genetic generalized epilepsy and their relatives in extended families.

METHODS

A structured interview based on International League Against Epilepsy (ILAE) and International Classification of Sleep Disorders (ICSD-3) criteria was applied to 67 index cases and their relatives to determine genetic generalized epilepsy subtypes and assess the occurrence of sleepwalking or sleep paralysis. Bivariate analysis was performed using chi-square and Fisher exact tests.

RESULTS

The prevalence of sleepwalking and sleep paralysis was 15.3% (95% confidence interval 12.1-18.9) and 11.7% (95% confidence interval 8.7-15.3), respectively. Unusually, no sleepwalkers were found among individuals displaying epilepsy with generalized tonic-clonic seizures. Approximately a quarter of the patients had either parasomnia or genetic generalized epilepsy. Over half the genetic generalized epilepsy families had at least 1 individual with sleepwalking, and more than 40% of the families had one individual with sleep paralysis.

CONCLUSION

The prevalence of sleepwalking or sleep paralysis is reported for individuals with genetic generalized epilepsy and their relatives. The co-existence of either parasomnia in the genetic generalized epilepsy patients and the co-aggregation within their families let suggest that shared heritability and pathophysiological mechanisms exist between these disorders. We hypothesize that sleepwalking/sleep paralysis and genetic generalized epilepsy could be variable expression of genes in shared pathways.

Sleep Paralysis Among Egyptian College Students: Association With Anxiety Symptoms (PTSD, Trait Anxiety, Pathological Worry)

Among Egyptian college students in Cairo (n = 100), this study examined the relationship between sleep paralysis (SP) and anxiety symptoms, viz., posttraumatic stress disorder (PTSD), trait anxiety, and pathological worry. SP rates were high; 43% of participants reported at least one lifetime episode of SP, and 24% of those who reported at least one lifetime episode had experienced four or more episodes during the previous year. Fourteen percent of men had experienced SP as compared to 86% of women. As hypothesized, relative to non-SP experiencers, participants who had SP reported higher symptoms of PTSD, trait anxiety, and pathological worry. Also, as hypothesized, the experiencing of hypnogogic/hypnopompic hallucinations during SP, even after controlling for negative affect, was highly correlated with symptoms of PTSD and trait anxiety. The study also investigated possible mechanisms by examining the relationship of hallucinations to anxiety variables.

Isolated sleep paralysis and hypnic hallucinations in schizophrenia

BACKGROUND

Usually remembered in the context of Narcolepsy-Cataplexy syndrome, isolated sleep paralysis (SP) and hypnic hallucination are widely prevalent and because of the overlap of symptoms with schizophrenia, their identification is important but unrecognized.

AIMS

To determine the presence of SP and hypnic hallucinations (HH) in people with schizophrenia and schizoaffective disorder.

STUDY DESIGN

Cross-sectional survey.

METHODS

Participants were patients receiving follow-up care for schizophrenia from Assertive Community Treatment Team. A screening questionnaire was administered during their routine follow-up visits.

RESULTS

Of 71 respondents (49 males, 22 females) only 11 (10 males and 1 female), that is, 15% reported SP, and 12 (7 males and 5 females), that is, 16.9% reported HH, a considerably low prevalence.

CONCLUSION

It is difficult to study the presence of SP and HH in patients with active or residual symptoms of schizophrenia, and more refined studies and appropriate questionnaires are required. The possibility of SP and HH confounding or being misdiagnosed as psychotic symptoms needs to be borne in mind.

Rates and characteristics of sleep paralysis in the general population of Denmark and Egypt

In the current research we report data from two studies that examined rates and characteristics of sleep paralysis (SP) in the general population of Denmark and Egypt. In Study I, individuals from Denmark and Egypt did not differ in age whereas there were more males in the Egyptian sample (47 vs. 64 %); in Study II, individuals from Denmark and Egypt were comparable in terms of age and gender distribution. In Study I we found that significantly fewer individuals had experienced SP in Denmark [25 % (56/223)] than in Egypt [44 % (207/470)] p < .001. In Study II we found that individuals who had experienced at least one lifetime episode of SP from Denmark (n = 58) as compared to those from Egypt (n = 143) reported significantly fewer SP episodes in a lifetime relative to SP experiencers from Egypt (M = 6.0 vs. M = 19.4, p < .001). SP in the Egyptian sample was characterized by high rates of SP (as compared to in Denmark), frequent occurrences (three times that in the Denmark sample), prolonged immobility during SP, and great fear of dying from the experience. In addition, in Egypt, believing SP to be precipitated by the supernatural was associated with fear of the experience and longer SP immobility. Findings are discussed in the context of cultural elaboration and salience theories of SP.

Minority inclusion in randomized clinical trials of panic disorder

In 1993, the National Institutes of Health issued a mandate that funded research must include participation by racial and ethnic minority groups, and researchers were required to include in their proposals strategies by which they would achieve diversity in their samples. A methodological search for randomized clinical trials of panic disorder was conducted to evaluate ethnoracial differences in panic disorder symptoms, rates of minority inclusion in North American studies, and effective methods of minority recruitment. Less than half of the studies identified reported ethnic and racial data for their sample. Of the 21 studies that did report this information (n=2687), 82.7% were European American/non-Hispanic White, 4.9% were African American/Black, 3.4% were Hispanic, 1.1% were Asian American, and 1.4% were another ethnicity. The remaining 6.5% was simply classified as other/non-White. The primary recruitment techniques utilized were clinical referral and advertising, but neither of these methods were correlated with improved minority participation, nor was the number of recruitment sites. As minorities are greatly underrepresented in panic disorder studies, reported treatment outcomes may not generalize to all ethnic and cultural groups. Researchers have not followed NIH guidelines regarding inclusion of special populations. Inclusion of minorities in future studies is needed to fully understand issues related to the treatment of panic disorder in non-White populations. Suggestions for improved recruitment of ethnoracial minorities are discussed.

The Manifestation of Anxiety among Sesotho Speakers

Mental health research in black communities in South Africa has been neglected to an alarming degree. Consequently the health system is in a precarious situation owing to a lack of accurate data to facilitate proper planning. This study investigates the way in which anxiety is clinically manifested among Sesotho speakers. For this exploratory descriptive study, the participants consisted of 101 Sesotho speakers diagnosed with anxiety disorders. They were drawn from the population of patients visiting various health establishments in the Mangaung area, South Africa. A semi-structured interview based on the Psychiatric Interview Questionnaire was used to evaluate the participants. It consisted of two types of data collection: the open-ended interview and clinical observation. The results show that there were marked differences in the presentation of anxiety symptoms among Sesotho speakers in comparison with what has been reported in western literature. Anxiety among Sesotho speakers is characterized by the prevalence of hallucinations, and there are also overlapping symptoms of anxiety and depression.

The assessment of the phenomenology of sleep paralysis: the Unusual Sleep Experiences Questionnaire (USEQ)

Previous research has found a relationship between sleep paralysis (SP) and anxiety states and higher rates have been reported among certain ethnic groups. To advance the cross-cultural study of SP, we developed a brief assessment instrument (which can be self-administered), the Unusual Sleep Experiences Questionnaire (USEQ). In this article, we report on a pilot study with the USEQ in a sample of 208 college students. The instrument was easily understood by the participants, with one quarter reporting at least one lifetime episode of SP. As in previous studies, SP was associated with anxiety (in particular, panic attacks).

Biological variations in depression and anxiety between East and West

Ethnicity and culture represent important factors in shaping psychopathology as well as pharmacotherapeutic responses in psychiatric patients. A large body of literature, accumulated over the past several decades, demonstrates that these factors not only determine the metabolism and disposition of medications (pharmacokinetics), but also their interactions with therapeutic targets (pharmacodynamics). This article focuses on the impact of such variations on the diagnosis and treatment of depression and anxiety disorders between East and West. Genes controlling the expression of drug metabolizing enzymes as well as the function of the brain are highly polymorphic, and the patterns and distribution of these polymorphisms are typically divergent across ethnic groups. To the extent that these genetic patterns determine drug response, ethnic variations in these genetic dispositions will lead to differential responses in clinical settings. In addition, the expression of these genes is significantly influenced by environmental factors including diet as well as exposure to other natural products. Superimposed on these biological influences, culturally determined beliefs and behavioral patterns also profoundly influence patients' expectations of treatment response, adherence, and interactions with clinicians. In addition to pharmacotherapeutic responses, emerging data also indicate that significant ethnic variations exist in genetic polymorphisms and neurobiologic correlates (biomarkers) that may be associated with the vulnerability to psychiatric disorders. These considerations argue for the importance of examining biological variations across ethnic groups, especially in the clinical context, in terms of the assessment and treatment of psychiatric patients, and in our understanding of psychiatric phenomenology and nosology.

Lifetime prevalence and incidence of parasomnias in a population of young adult Nigerians

Lifetime prevalence, incidence, and risk factors for parasomnias were determined. Past experiences of non-REM, REM, and sleep-transition parasomnias were recorded. Diaries of night sleep duration, parasomnias, perception of aliens, levels of physical activity, headaches and intake of all substances, drugs, and tobacco were kept for 14 consecutive days. A total of 276 subjects were studied. Lifetime prevalences (95% CI) were 725 (668-776) for occurrence of any parasomnia, 43 (25-74) for sleepwalking, 112 (80-155) for sleep terror, 475 (416-533) for nightmares, 225 (179-277) for sleep paralysis, 43 (25-74) for sleep starts, 322 (270-380) for sleep talking, and 344 (291-402) for enuresis. Incidences (95% CI) were 210 (166-262) for occurrence of any parasomnia, 14 (6-37) for sleepwalking, 11 (4-31) for sleep terror, 170 (131-219) for confusional arousal, 18 (8-42) for nightmares, 14 (6-37) for sleep paralysis, 33 (17-61) for sleep starts, and 4 (1-20) for sleep enuresis. Multivariate analysis showed associations of increase occurrence of parasomnias and duration of sleep >7 h (p < 0.05) and intake of alcohol (p < 0.001), but heavy workload before sleep was associated with decreased occurrence of parasomnias (p < 0.01). Gender, smoking, caffeinated drinks, hypnotics, and headaches were not associated with parasomnias. Incidence of presence of aliens (95% CI) in the room was 25(0/infinity) (12-51). This study shows that more than 70% of the population have experienced parasomnias at any time in the past. Nightmares, enuresis, sleep paralysis and night terrors are the commonest parasomnias experienced in the past, while confusional arousal, sleep starts, and nightmares are the commonest parasomnias currently experienced. Incidence estimates show that all parasomnias persist into adulthood at reduced rates, but reduction of occurrence was greatest for enuresis. Long duration of night sleep and intake of alcohol predisposed subjects to higher occurrence of parasomnias.

The nightmares of Puerto Ricans: an embodied 'altered states of consciousness' perspective

This article examines nightmare narratives collected as part of a person-centered ethnographic study of altered states of consciousness (ASCs) and supernaturalism in a mainland Puerto Rican community in the late 1990s. Utilizing a descriptive backdrop informed by cross-cultural studies of ASCs and highlighting the relevance of recent insights from the cognitive sciences of religion and from the anthropology of embodiment or cultural phenomenology, I examine the lived experience and psychocultural elaboration of diverse Puerto Rican nightmare events. Taking the nightmare to be a trauma in its waking-nightmare sense (i.e., through the extreme fright caused by sleep paralysis) as well as an intrusive, traumatic memory in its posttraumatic sense (i.e., a reliving of trauma themes in dreams), I show how the perceptual and interpretive processes evoked by intensely affective ASCs both inform and are informed by Puerto Rican religious and spiritualistic orientations and values.

Sleep paralysis and trauma, psychiatric symptoms and disorders in an adult African American population attending primary medical care

The occurrence of sleep paralysis (SP) absent narcolepsy appears to not be uncommon in African Americans and probably other non-European groups. Prior research has linked SP to trauma and psychiatric disorders and suggested a specific relationship to panic disorder in African Americans. The objective of our study was to evaluate relationships of SP with trauma, concurrent psychiatric symptoms and lifetime psychiatric diagnoses in an adult African American population recruited from primary care. Cross sectional study with surveys and diagnostic interviews; Patients attending primary care clinics filled out a survey that determined the 6 month prevalence and associated features of SP, a panic disorder screen, the self-rated Hamilton Depression Scale, and an inventory of trauma exposure. A subset of trauma-exposed participants (N = 142) received comprehensive diagnostic interviews that incorporated the Structured Clinical Interview for DSM-IV and the Clinician Assessed PTSD Scale. Four hundred and forty-one adults participated (mean age-40.0 SD = 13.3, 68% female, 95% African American). Fourteen percent endorsed recent SP. In approximately 1/3 of those with SP, episodes also featured panic symptoms. SP was strongly associated with trauma history, and concurrent anxiety and mood symptoms. SP was not associated with specific psychiatric disorders other than lifetime (but not current) alcohol or substance use disorders. Our findings suggest that SP is not uncommon in adult African Americans and is associated with trauma and concurrent distress but not with a specific psychiatric diagnosis.

Sensed presence as a correlate of sleep paralysis distress, social anxiety and waking state social imagery

Isolated sleep paralysis (ISP) is a common parasomnia characterized by an inability to move or speak and often accompanied by hallucinations of a sensed presence nearby. Recent research has linked ISP, and sensed presence more particularly, with social anxiety and other psychopathologies. The present study used a large sample of respondents to an internet questionnaire (N=193) to test whether these associations are due to a general personality factor, affect distress, which is implicated in nightmare suffering and hypothesized to involve dysfunctional social imagery processes. A new measure, ISP distress, was examined in relation to features of ISP experiences, to self-reported psychopathological diagnosis, to scores on the Leibowitz Social Anxiety Scale and to scores on a new questionnaire subscale assessing social imagery in a variety of waking states. Three main results were found: (1) ISP experiences are only weakly associated with a prior diagnosis of mental disorder, (2) sensed presence during ISP is associated preferentially with ISP distress, and (3) ISP distress is associated with dysfunctional social imagery. A general predisposition to affective distress may influence the distress associated with ISP experiences; overly passive social imagery may, in turn, be implicated in this affect distress influence.

Sleep and psychiatry

Psychiatric disorders constitute 15.4% of the disease burden in established market economies. Many psychiatric disorders are associated with sleep disturbances, and the relationship is often bidirectional. This paper reviews the prevalence of various psychiatric disorders, their clinical presentation, and their association with sleep disorders. Among the psychiatric disorders reviewed are affective disorders, psychosis, anxiety disorders (including posttraumatic stress disorder), substance abuse disorders, eating disorders, and attention deficit/hyperactivity disorders. The spectrum of associated sleep disorders includes insomnia, hypersomnia, nocturnal panic, sleep paralysis, hypnagogic hallucinations, restless legs/periodic limb movements of sleep, obstructive sleep apnea, and parasomnias. The effects on sleep of various psychotropic medications utilized to treat the above psychiatric disorders are summarized.

Sleep paralysis episode frequency and number, types, and structure of associated hallucinations

Sleep paralysis (SP) episodes are often accompanied by vivid hallucinoid experiences that have been found to fall into three major categories thought to be organized according to intrinsic rapid eye movement (REM) processes. Prior research has, however, combined data for individuals with varying degrees of experience with SP episodes, rendering interpretations of the source of this structure ambiguous. The present study of 5799 current SP experients compares the nature and structure of the hallucinations of novice SP experients with those reporting varying numbers of episodes. Both qualitative and quantitative differences were found in reported hallucinations as a function of episode frequency, although the underlying three-factor structure of the hallucinoid experiences was highly similar for all groups. Novice experients' reports were, however, characterized by clearer differentiation of factors, likely because of a tendency of experienced SP experients to conflate experiences across episodes. Age and age of onset of SP episodes were associated with differences in the variety and types of hallucinations but not their underlying structure. Earlier onset of SP episodes was also associated with more frequent episodes. The results are consistent with the hypothesis that the basic form and patterning of hallucinatory experiences is a result of intrinsic processes, independent of prior experience, likely associated with underlying REM neurophysiology.

Prevalence and illness beliefs of sleep paralysis among Chinese psychiatric patients in China and the United States

To investigate the prevalence and illness beliefs of sleep paralysis (SP) among Chinese patients in a psychiatric out-patient clinic, consecutive Chinese/Chinese-American patients who attended psychiatric out-patient clinics in Boston and Shanghai were asked about their lifetime prevalence, personal experience and perceptions regarding the causes, precipitating factors, consequences, and help-seeking of SP. During the 4-month study period, 42 non-psychotic psychiatric out-patients from the Boston site and 150 patients from the Shanghai site were interviewed. The prevalence of SP was found to be 26.2% in Boston and 23.3% in Shanghai. Patients with post-traumatic stress disorder (PTSD) or panic disorder reported a higher prevalence of SP than did patients without these disorders. Patients attributed SP to fatigue, stress, and other psychosocial factors. Although the experience has traditionally been labeled 'ghost oppression' among the Chinese, only two patients, one from each site, endorsed supernatural causes of their SP. Sleep paralysis is common among Chinese psychiatric out-patients. The endorsement of supernatural explanations for SP is rare among contemporary Chinese patients.