Global Incidence and Clinical Characteristics of Sleeping Paralysis: A Systematic Review and Meta-analysis
Mahmoud Tarek Hefnawy1, Basma Ehab Amer2, Samar Ahmed Amer3, Yehya Khlidj4, Bahaa Elfakharany5, Khaled Moghib6, Adel Mouffokes7, Nishant Parag Soni 8, Zainab Jamal Alazzeh9, Mohamed Elsayed10, Ahmed Negida11
1Faculty of Medicine Zagazig University, Egypt; Negida Academy, Arlington, MA, 2Faculty of medicine Banha University, Egypt, 3Zagazig University Faculty of Human Medicine Department of Community and Human Medicine, 4Faculty of Medicine, University of Algiers 1, Algiers, Algeria, 5Faculty of Allied Medical Sciences, Pharos University, Alexandria, Egypt. Medical Research Group of Egypt, Negida Academy, Arlington, MA, 6Kasralainy Faculty of Medicine, Cairo University., 7Faculty of Medicine, University of Oran, Algeria, 8GMERS Medical College and Hospital, Ahmedabad, India., 9Jordanian University of Science and Technology, Jordan, 10Department of Psychiatry and Psychotherapy III, University of Ulm, Leimgrubenweg 12-14, 89075, Ulm, Germany, 11Virginia Commonwealth University
Objective:
Our objectives are to identify SP's global prevalence, the affected population's characteristics, and the SP's clinical picture.
Background:
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.
Design/Methods:
We searched Three databases ( Pubmed, Scopus & WOS) to identify eligible studies using a unique search strategy. 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.
Results:
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 nonisolated SP (33%, 95% CI [26%, 42%], I2 = 97%, P <0.01; 31%, 95% CI [21%, 43%], I2 = 100%, P = 0, respectively). Subgroup analysis showed that the majority of those who experienced SP were psychiatric patients (35%, 95% CI [20%, 55%], I2 = 96%, P <0.01), particularly in patients with post-traumatic stress disorder (PTSD) and panic disorders (60%, 95% CI [13%, 94%], I2 = 97%, P <0.01, respectively). 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. 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.
Conclusions:
Our findings revealed that 30% of the population suffered from SP, especially among psychiatric patients and students. Patients with PTSD and panic disorder were the majority to be affected by SP.