Sleep paralysis (SP) is a psychobiological phenomenon caused by temporary desynchrony in the architecture of rapid eye movement (REM) sleep. It affects approximately 7.6% of the general population during their lifetime. The aim of this study was to assess (1) the prevalence of SP among Polish students in Lublin (n = 439) using self-reported online surveys, (2) the frequency of SP-related somatic and psychopathologic symptoms, and (3) the factors potentially affecting the occurrence of symptoms among people experiencing SP. We found that the incidence of SP in the Polish student population was slightly higher (32%) than the average prevalence found in other student populations (28.3%). The SP clinical picture was dominated by somatic symptomatology: 94% of respondents reported somatic symptoms (most commonly tachycardia, 76%), 93% reported fear (most commonly fear of death, 46%), and 66% reported hallucinations (most commonly visual hallucinations, 37%). The number of SP episodes was related to sleep duration and supine position during sleep. The severity of somatic symptoms correlated with lifestyle variables and anxiety symptomatology. Our study shows that a significant proportion of students experience recurrent SP and that this phenomenon is associated with fear and physical discomfort. The scale of the phenomenon requires a deeper analysis.

Summary Introduction: Sleep paralysis (SP) is a condition that widely occurs among people all over the world. It has been known for thousands of years and is rooted in the culture of many countries. It arouses strong emotions, though still little is known about it. The clinical picture of the disorder can be very diverse. It is often accompanied by hypnopompic and hypnagogic hallucinations, somatic complaints and the feeling of intense anxiety. A feeling of paralysis in the body with inhibited consciousness is always observed with the experience. SP pathophysiology is not fully understood, however, most theories explaining this phenomenon are based on the assumption that it results from dysfunctional overlap of REM sleep and wakefulness. It is experienced by healthy people, but it is more often associated with somatic and mental disorders, which is why it is becoming an object of interest for researchers. Aim: The aim of this work is to present the most important information about the disorder known as sleep paralysis - its history, cultural context, pathophysiology, prevalence, symptomatology, coexistence with other somatic and mental disorders as well as diagnostics and available forms of prevention and treatment. Materials and methodology: The available literature was reviewed using the Google Scholar bibliographic databases searching the following keywords: sleep paralysis, REM sleep parasomnias, sleep disorder, night terrors and time descriptors: 1980-2018. Results 1. Sleep paralysis has already been described in antiquity, and interpretations related to its occurrence are largely dependent on culture and beliefs. 2. Symptomatology of the disorder is very diverse: both mental and somatic symptoms are present. 3. The pathophysiology of the disorder has not been fully explained. The basis of most theories regarding sleep paralysis is the assumption that it results from the dysfunctional overlap of REM sleep and wakefulness. 4. The prevalence of SP at least once in a lifetime is 7.6% in the general population, although it is estimated that it is much more frequent in people with various mental and somatic disorders. 5. Treatment of SP is associated with a change in lifestyle and the use of pharmacotherapy and psychotherapy.

Background: Sleep paralysis (SP) is a transit dissociative state associated with the REM sleep phase that affects approximately 28.3% of the student population during their lifetime. The reasons for the high prevalence of SP in the student population are not entirely clear. Research indicates possible influencing factors such as the intensification of anxiety symptoms, a tendency to worry, the presence of PTSD symptoms, and behavioral factors such as the consumption of psychoactive substances (caffeine, alcohol, nicotine) and poor sleep hygiene. The study aimed to assess the prevalence of SP and its risk factors in the Polish student population. Methods: The study used a battery online consisting of a set of questionnaires (a personal questionnaire, 2) the SP-EPQ, 3) the PCL -5, 4) the STAI-T, 5) the PSWQ). The questionnaire was sent via Facebook to 4500 randomly selected students from different universities in Poland. The questionnaire was completed by 2598 students. To unify the participant sample, people over 35 were excluded from the study (45 students). Ultimately, data from 2553 students were analyzed. Results: A total of 33.14% of individuals experienced at least one episode of SP in their lives. The highest odds ratio for SP was associated with: the presence of three or more health problems (OR: 2.3; p = 0.002), the presence of any mental disorder (OR: 1.77; p = 0.002), including mood disorders (OR: 2.07 ; p = 0.002), suffering from at least one somatic disorder (OR: 1.34; p = 0.002), a high level of anxiety as a constant personality trait (OR: 1.20; p = 0.035) and smoking (OR: 1.48; p = 0.0002), alcohol consumption (OR: 1.52; p <0.0001), physical activity (OR: 1.31; p = 0.001). Conclusions: The results of our research indicate that a large proportion of students experienced isolated sleep paralysis. Mental and somatic health problems and lifestyle factors were found to predispose to this disorder. Due to the numerous risk factors for SP, it is necessary to conduct additional research to confirm the impact of these factors and to investigate the mechanisms of their influence on SP.

Sleep paralysis (SP) is a hypnagogic or hypnopompic state associated with the inability to move while conscious. Recurrent isolated sleep paralysis (RISP) is a type of REM parasomnia. Individuals experiencing anxiety disorders, PTSD, exposure to chronic stress, or shift work are at risk of developing this sleep disorder. This study aimed to assess: (1) the prevalence, frequency, and symptomatology of SP, and (2) the impact of the severity of anxiety symptoms, perceived stress, and lifestyle mode variables on the frequency and severity of SP in four professional groups at high risk of SP (n = 844): nurses and midwives (n = 172), policemen (n = 174), teachers (n = 107), and a group of mixed professions—“other professions” (n = 391). The study used a battery of online questionnaires: the Sociodemographic and Health Status Questionnaire, the SP-EPQ, the PCL -5, the STAI-T, the PSWQ and the PSS-10. The prevalence of SP was the lowest among policemen (15.5%) and the highest in the group of “other professions” (39.4%). The association of SP with symptoms of PTSD and anxiety was confirmed in the group of nurses and “other professions”. Among other factors modulating the incidence and severity of SP were: age, BMI, smoking, alcohol consumption, sleep duration, and perceived stress. This study indicates that there exist links between SP and psychological and lifestyle factors, suggesting a complex etiology for this sleep disorder. Due to the high prevalence of SP in the studied groups of occupations, further research is necessary to develop preventive and therapeutic methods for SP.

Background Sleep paralysis (SP) is a transitional dissociative state associated with the REM sleep phase that affects approximately 28.3% of the student population during their lifetime. The reasons for the high prevalence of SP in the student population are not entirely clear. Research indicates possible influencing factors such as the intensification of anxiety symptoms, a tendency to worry, the presence of PTSD symptoms, and behavioral factors such as the consumption of psychoactive substances (caffeine, alcohol, nicotine), sleep deprivations and poor sleep hygiene. The study aimed to assess the prevalence of SP and determine the risk factors for the occurrence of SP in the population of Polish students. Methods The study used a battery online consisting of a set of questionnaires 1) a personal questionnaire, 2) the SP-EPQ, 3) the PCL −5, 4) the STAI-T, 5) the PSWQ. The questionnaire was sent via Facebook to 4500 randomly selected students from different universities in Poland. The questionnaire was completed by 2598 students. To unify the participant sample, people over 35 were excluded from the study (45 students). Ultimately, data from 2553 students were analyzed. Results A total of 33.14% of individuals experienced at least one episode of SP in their lives. The highest odds ratio for SP was associated with: the presence of three or more health problems (OR: 2.3; p = 0.002), the presence of any mental disorder (OR: 1.77; p = 0.002), including mood disorders (OR: 2.07; p = 0.002), suffering from at least one somatic disease (OR: 1.34; p = 0.002), a high level of anxiety as a constant personality trait (OR: 1.20; p = 0.035) and smoking (OR: 1.48; p = 0.0002), alcohol consumption (OR: 1.52; p < 0.0001), physical activity (OR: 1.31; p = 0.001). Conclusions The results of our research indicate that a large proportion of students experienced isolated sleep paralysis. Mental and somatic health problems and lifestyle factors were found to predispose individuals to this disorder. Due to the numerous risk factors for SP, it is necessary to conduct additional research to confirm the impact of these factors and to investigate the mechanisms of their influence on SP.