Abstract
Objectives: To assess prevalence and perception of sleep paralysis and its relationship with socioeconomic determinants, and risk factors in a cross-sectional sample of Saudi general population from Al-Ahsa city.
Methods: A cross-sectional sampling survey was conducted during 2020 to 2021. The targets were aged above 18 and belonged to Al-Ahsa. Patients were sent self-reported anonymous questionnaires to complete.
Results: A total of 524 participants, whose ages ranged from 18 to 60 years, were analyzed. Among 85.7% of participants aged 55 years and over, compared to 65.8% of those who were aged under 35, 379 (72.3%) respondents were females. Moreover, 438 (83.6%) participants were university graduates, 271 (51.7%) were students and 40.8% had psychological disorders including anxiety (25.2%) and depression (5.7%). Family history of sleep paralysis was reported by 369 (70.4%) participants. A total of 97.5% study participants were aware of sleep paralysis.
Conclusion: Sleep paralysis is a common occurrence in people residing in Al-Ahsa, Saudi Arabia. A considerable number of the society held wrong beliefs regarding sleep paralysis. Therefore, raising public of identity of sleep paralysis is crucial. We recommend applying the study in other cities within Saudi Arabia to identify common risk factors and perceptions among the society.
Sleep paralysis (SP) is a common conflict phenomenon currently under research with unknown causes. Sleep paralysis is characterized as a transient period during which voluntary muscle movement is inhibited, yet respiratory and ocular movement remain intact.1 These episodes can occur at the onset of sleep or upon awakening in the morning or during the night. Commonly, women suffer from SP, which is more likely to occur when individuals sleep in the supine position.2 It is a type of rapid eye movement (REM) parasomnia that causes an increase in the blood pressure, breathing rate and heart rate.3 Only under 8% of the general population are affected by SP during their lifetime, and is known as isolated SP if it occurs in healthy individuals.4 A study held in Japan shows that SP was prevalent in more than 2% of the Japanese population.5,6 Sleep paralysis is more ubiquitous in people with Chinese background with prevalence of 41% and African American background with prevalence of 37%.7,8 With respect to Saudi Arabia, a study by Wali et al9 shows that 16% of Saudi healthcare workers suffered from SP symptoms. Even though only 7.6% of the general population are affected by SP, students and patients who have psychiatric manifestations, such as trauma history, posttraumatic stress disorders, anxiety sensitivity, and panic disorders, are the majority suffering from SP at 28.3% and 31.4%, respectively.10,11 In addition, sleep-related factors, such as sleep deprivation, shift work, jet lag, and a few medical conditions, such as hypertension,seem to have a connection with SP.12-14 The presence of nightmares play a core role factor for more frequent episodes of SP.10 Nevertheless, people’s perceptions of SP as a supernatural power can be a risk factor of SP.15-17 In Saudi Arabia, SP is described as Al-Jathoum, and a case study in which a Saudi patient, who at first complained of sleep disruption due to driving long distances and nightmares, described it as a type of alien power, likely to be jin that squeezed his chest for a period of time.18
There is an ultimate need to conduct this study due to the significance of the prevalence of SP worldwide, and the importance of identifying SP as a medical condition rather than cultural misconceptions. Despite the progress of studies regarding SP in Saudi Arabia, no study has reported the attitudes of Saudi people with respect to SP. Therefore, this present study is designed to assess the perception of SP and its relationship with socioeconomic determinants, risk factors associated with SP and its prevalence in a cross-sectional sample of Saudi general population from Al-Ahsa city, the most populated city in the eastern province of Saudi Arabia.
Methods
A cross-sectional-study was conducted in Al-Ahsa, Saudi Arabia during 2020 to 2021. Qualitative analysis was conducted to investigate the various perceptions regarding SP, risk factors related to SP, the phenomenon of SP and the relationship between SP and psychiatric disorders, depending on the participants’ answers. The sample size, which was calculated by the Raosoft sample size calculator according to the total number of the population in Al-Ahsa, was around 385 participants. However, the actual sample collected during the distribution of questionnaires was 536 participants due to high responses from people. The sample was randomly selected by distributing an electronic questionnaire through 2 social media platforms, WhatsApp and Twitter. It was the most appropriate way to reach participants from different areas within the Al-Ahsa region. This questionnaire was designed by the research authors and validated by 3 neurological consultants. The target population comprised of adults aged 18 and above and included both male and female subjects. Participants below the age of 18, or those who did not live within the Al-Ahsa region, were excluded from the study. Likewise, questionnaires, which were not fully filled out were eliminated.
Data was collected with the help of a self-administered questionnaire using Google form survey, which comprised of 26 multiple choice questions (Appendix 1). An Arabic version of this questionnaire was also produced and distributed amongst the participants (Appendix 2). The questionnaire contained 6 sections: personal data, SP phenomenon, perception regarding SP, risk factors, sleep quality, and SP relationship with different psychiatric disorders. Ethical research approval was obtain from the Deanship of Scientific Research from Imam Abdulrahman Bin Faisal University. The questionnaire was used for research purposes, and thus, the information was not used for any other goals. Participant privacy was a top priority in this research, and therefore, any questions that might lead to the discovery of the participants identity were not included. An informed consent was obtained and was an essential condition to participate in study (Appendix 3).
Statistical analysis
Data was modified, coded, and entered into the statistical software SPSS version 22 (IBMCorp, Armonk, NY, USA). All statistical analyses were carried out by employing 2 tailed tests. A p-value of less than 0.05 was statistically significant. In addition, a descriptive analysis based on frequency and percent distribution was done for all variables. A Pearson Chi-square test was also used to test for relations’ significance.
Results
The study included 524 participants, whose ages ranged from 18 to 60 years, with a mean age of 21.6 ± 11.8 years old. There were 379 (72.3%) female respondents, of which 300 (57.3%) were single, 438 (83.6%) were university graduates, 271 (51.7%) were students, and 40.8% had psychological disorders, namely anxiety (25.2%) and depression (5.7%). Family history of SP was reported by 369 (70.4%) participants (Table 1).
Table 2 & Figure 1 demonstrate the prevalence and pattern of SP among the population in Al-Ahsa. A total of 360 (68.7%) participants reported that they had SP attacks; however, only 8 (2.2%) asked for medical consultation. Attacks repeated for up to 3 times among 181 (50.3%) participants and for more than 6 times among 115 (31.9%) respondents. Majority of the participants experienced their first attacks between the age of 18-35 (95%) years.
Considering the perceived awareness of the general population towards the SP phenomenon and its related risk factors (Table 3), 97.5% of the study participants were aware of SP. 3.8% of the participants reported that during SP attacks, they felt pressure on their chest or body, and 34.4% were told that SP is a medical condition. Furthermore, visiting specialized physicians and being aware of the risk factors to avoid frequent SP phenomena was mentioned by 24.8% of the participants. Regarding perceived awareness of SP risk factors, 63% of the participants thought that psychological disorders are related to SP phenomena. Similarly, 59.5% thought that the sleeping position is related to the occurrence of SP phenomena, especially lying on your back (74.5%), and on your abdomen (18.2%). Nearly 88% of the participants did not hold the opinion that medications are risk factors of SP. Furthermore, 45.8% of the participants believed that sleep disorders are associated with SP phenomena, while 34.5% reported that weak faith is related to SP phenomena. Additionally, 28.4% were convinced that there is a link between watching horror movies and SP phenomena.
Table 4 illustrates the relation between public sleep patterns and SP phenomena. 18.3% of the participants with SP sleep for less than 5 hours a day, in comparison to 10.4% of those without the condition, with a recorded statistical significance (p=0.038). Moreover, 33.3% of the participants with SP reported waking up early in the morning and had difficulty in going back to sleep, compared to 23.8% of those with no SP history (p=0.048). 23.6% of the participants with SP felt excessive sleepiness during the daytime in comparison to 23.8% of those without SP, with a borderline statistical significance (p=0.060). Sleep-related hygiene was insignificantly associated with SP phenomena.
Table 5 shows determinants of SP phenomena among the general population. Sleep paralysis was detected among 85.7% of participants aged 55 years and over, compared to 65.8% of those who were aged under 35, with a recorded statistical significance (p=0.010). Likewise, 76.3% of the married participants had experienced SP, compared to 63% of the single participants (p=0.001). Sleep paralysis was detected among 94.7% of retired respondents in comparison to 63.1% of students (p=0.007). Furthermore, 73.2% of the respondents, who had psychological disorders also experienced SP, relative to 65.3% of those whose health status were normal (p=0.029). In similar fashion, SP was detected among 77.5% of those with family history of SP, compared to 47.7% of others without a family history of SP (p=0.001).
Discussion
The aim of this study was to investigate the SP phenomenon among people in Al-Ahsa. The results obtained from this study revealed that the prevalence of SP in Al-Ahsais 68.7%. On the other hand, a study published in Japan shows that prevalence of SP reached 40% of the whole sample.19 Similarly, a cross sectional study held in Bremen, Germany, demonstrates an increase in SP cases by 35%.20 However, variable measures of SP have been reported in adults in several countries, but the difference in prevalence between adolescents and adults is still unknown and thus, additional studies are required to further explore the subject. As stated in this study, females have a higher prevalence of sleep disorder than males. Likewise, a study by Shengli et al21 displays predominance of females on SP by 7.4%, whereas other studies observe higher rates in men.22,23 However, most of the studies do not show any significant differences with respect to gender.24,25
Based on outcomes, age is an important factor regarding the occurrence of SP.26 According to our study, 2 adult groups experience SP, ranging in age from 18 to 35 and 36 to 55 years old, with prevalence percentages of 65.8% and 80.7%, sequentially. This increase may be due to mental and physical pressures, such as educational expectations, irregular life rhythms, delayed sleep, or interpersonal stressors.27
Moreover, 77.5% have a family history of sleep paralysis. Identically, in a study of a single-family, it was noticed that within the 64 members studied, 33 of them reported at least one episode of SP experience.7 Moreover, a study held in UK revealed that 19 out of the 22 individuals in the same family had at least one attack of SP in their lives.17 This indicates that family studies can illustrate such characteristics within families, but they are not able to differentiate if the similarity within family members emerges from genetic or environmental factors.28
The present study indicates that SP was correlated with psychological disorders. Similarly, patients with a diagnosis of post-traumatic disorder (PTSD) in Cambodian, Chinese, and American samples showed higher prevalence of SP (65-100%) compared to healthy controls (20-25%).1 Furthermore, in a study focusing on fearful isolated SP in outpatients with panic attacks disorder, participants who confirmed diagnosis with panic attacks only were significantly less likely to experience frequent fearful isolated SP compared to patients diagnosed with both PTSD and pain attacks.29 Nevertheless, there is less evidence for an association between SP and depression, and in patients with anxiety disorder, a comorbid depression diagnosis was not linked to an increased prevalence in SP, compared to patients without comorbid depression.14
This study has shown that the supine position was the most common sleeping position for participants when SP occurred. Among the few studies on the association between SP and sleeping position, a study by Cheyne et al12 found that a greater number of individuals reported SP in the supine position than all other positions combined.
This study indicates a few differences in the factors associated with SP. The first factor is association with medication. Our study suggests that there is no association between SP and mediation. Specifically, a study by Otto et al14 found that the study results did not support an independent association between antidepressant/anxiolytic use and SP. In contrast, a study by Ohayon et al28 reported that SP was frequently observed in the users of anxiolytic medication. The second factor includes the association with anxiety. The present study found that there is a significant association between anxiety disorder and SP. However, most studies have not assessed a link of direct association between anxiety disorders as a significant predictor of SP.30 The third aspect is the association with sleep disorder. In our study, only 45.8% of the participants thought that sleep disorders are related to SP phenomena. Likewise, a large population-study held in Pennsylvania showed that insomnia was not associated with an increase in the prevalence of SP.28 However, nonrestorative sleep, one of the common symptoms of insomnia, was linked with increased SP rates.1 In a further study published in USA, disrupted sleep (waking up repeatedly during the night) was a significant predictor of SP. Five nights of sleep disruptions per month is 3 times more likely to result in SP phenomena compared to those reporting less than 5 nights per month.29
Study limitations
This study includes collection of data with the help of social media, which may not show accurate result as a hand-to-hand survey. Moreover, people were asked if they had psychiatric disorders; however, not many patients with psychiatric disorders are aware of their condition. A considerable number of patients who believed that there is a relationship between medications and SP did not name the medications that can be related to SP. As a result, this study was not able to specify the medications used for SP.
In conclusion, the SP phenomenon is a common condition in Al-Ahsa, Saudi Arabia. However, it is still under-researched. A higher percentage of the society holds wrong beliefs regarding SP, deeming of it as merely a nightmare rather than a medical condition. Moreover, many thought that the right way to prevent such events from happening is to do religious rituals. Therefore, it is important to raise public awareness on SP and how it should be approached. This condition is significantly associated with people who are married, retired, more than 55 years old, have a psychological disorder or a family history of SP. Most of the participants believed that psychiatric disorders and sleeping positions, especially being on the back, are the common risk factors of SP.
Furthermore, we recommend applying the study in other cities within Saudi Arabia to identify common risk factors and perceptions among the society and to correct the wrong beliefs held as well as limit risk factors.
APPENDIX 1 - Sleep paralysis questionnaires (English version).
APPENDIX 2 - Sleep paralysis questionnaires (Arabic version).
Acknowledgment
The completion of this research could not have been possible without the participation and assistance of Dr. Danah Aljaafari, Dr. Anas Aldehailan, Dr. Abdulla Alsuilman, Dr. Mohammed Almuaigel, and Ms. Fatimah Alhumud. Their contributions are sincerely appreciated and gratefully acknowledged.
Footnotes
Disclosure. Authors have no conflict of interests, and the research was not supported or funded by any drug company.
- Received August 6, 2021.
- Accepted October 4, 2021.
- Copyright: © Saudi Medical Journal
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