Sleep Paralysis among Professional Firefighters and a Possible Association with PTSD—Online Survey-Based Study
Abstract
:1. Introduction
2. Materials and Methods
2.1. Study Participants and Procedure
2.2. Materials
2.2.1. Personal Questionnaire
- I.
- Personal data, i.e., gender, age, height, weight.
- II.
- Lifestyle data, i.e., smoking (number of cigarettes smoked during the day, lifetime use of cigarettes measured in pack-year), use of energizing substances (number of cups of coffee during the day), alcohol consumption (frequency of alcohol consumption during the month), the average number of hours of sleep during the day, physical activity (number of hours per week devoted to physical activity).
- III.
- Health data, i.e., the presence of chronic diseases and medications taken.
2.2.2. The Sleep Paralysis Experience and Phenomenology Questionnaire (SP-EPQ)
2.2.3. PTSD Checklist (PCL-5)
2.2.4. The Perceived Stress Scale (PSS-10)
2.2.5. The State-Trait Anxiety Inventory (STAI-T)
2.2.6. The Penn State Worry Questionnaire (PSWQ)
2.2.7. Statistical Analysis/Data Analysis
3. Results
3.1. Demographic Characteristics and Health Status of Respondents
3.2. SP Incidence
3.3. The Relationship between SP and PTSD
3.3.1. SP and Severity of Symptoms of Post-Traumatic Stress Disorder (PTSD)
3.3.2. Prevalence of SP in Officers with a High Probability of PTSD (PCL-5 ≥ 33 points)
3.3.3. Chance of Occurrence of SP in Officers with a High Probability of PTSD (PCL-5 ≥ 33 Points)
3.4. SP and the Intensity of Perceived Stress (PSS-10)
3.5. The Relationship between SP and the Individual Tendency to Feel Anxious and Worried
3.5.1. SP and Individual Tendency to Feel Anxiety
3.5.2. SP and a Tendency to Worry
3.6. Lifestyle and SP Occurrence
3.7. Predictors of Sleep Paralysis in Multiple Stepwise Regression Model
4. Discussion
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Sample Type | SP + | SP − | |
---|---|---|---|
N | 72 | 759 | |
Female N | 4 | 23 | |
Male N | 68 | 736 | |
Age | M (SD) | 34.5 (6.82) | 36 (7.64) |
RNG | 23–51 | 18–50 | |
BMI (kg/m2) Z = 4.06 *** | M (SD) | 25.14 (2.58) | 26.66 (3.15) |
Me | 24.97 | 26.29 | |
RNG | 19.38–33.51 | 17.93–50.04 | |
Psychiatric Disorder N | All | 1 | 5 |
Depression | 1 | 2 | |
PTSD | - | 1 | |
Alcohol addiction | - | 1 | |
Insomnia | - | 1 | |
Somatic disorder n | All | 7 | 58 |
Endocrine Disorders | 1 | 7 | |
Hypertension | 3 | 25 | |
Allergic and Atopic Disorders | 1 | 6 | |
Gastrointestinal Disorders | 1 | 5 | |
Musculoskeletal disease | 1 | 7 | |
Others (n) | - | Sarcoidosis (1), Myopia (1), Deafness (1), Lyme disease (1), Glaucoma (1), chronic sinusitis (1), Psoriasis (1), Anemia (1) | |
Medicines taken (medications taken on a permanent basis) n | All | 7 | 54 |
Psychiatric/hypnotic medications (n) | Sertraline (1) | sertraline + lithium (1), opipramol and escitalopram (1), mianserin (1), trazodone + citalopram (1) |
SP+ | SP− | ||||||
---|---|---|---|---|---|---|---|
Self-Report Measures | Me | M | (SD) | Me | M | (SD) | Z |
PCL overall score | 19.0 | 21.35 | (19.39) | 12.0 | 15.40 | (14.62) | 2.29 * |
PTSD—Re-experiencing | 3.0 | 5.01 | (5.19) | 2.0 | 3.43 | (3.91) | 2.39 * |
PTSD—Increased arousal and reactivity | 7.0 | 7.54 | (6.19) | 5.9 | 5.57 | (4.98) | 2.48 * |
Number of Points in the PCL-5 Scale and Four Subscales | PTSD—Overall Score | PTSD—Re-experiencing | PTSD—Avoidance | PTSD—Negative Alterations in Cognition and Mood | PTSD—Increased Arousal and Reactivity |
---|---|---|---|---|---|
Number of SP episodes in the past month | 0.35 | 0.34 | 0.28 | 0.37 | 0.28 |
Number of SP episodes in the past year | 0.52 | 0.53 | 0.44 | 0.46 | 0.49 |
Number of SP episodes in one’s lifetime | 0.33 | 0.26 | 0.27 | 0.31 | 0.37 |
PTSD+ (n = 17) | PTSD− (n = 55) | ||||||
---|---|---|---|---|---|---|---|
Number of SP Episodes: | Me | M | (SD) | Me | M | (SD) | Z |
In the past month | 0 | 0.59 | (0.87) | 0 | 0.18 | (0.58) | 2.71 ** |
In the past year | 3.0 | 4.24 | (4.84) | 0 | 1.29 | (3.06) | 3.67 *** |
In one’s lifetime | 10.0 | 15.18 | (22.99) | 4.0 | 7.84 | (10.22) | 1.98 * |
Professional Firefighters | |||||||
---|---|---|---|---|---|---|---|
SP+ | SP− | ||||||
Me | M | (SD) | Me | M | (SD) | Z | |
BMI (kg/m2) | 24.97 | 25.14 | (2.58) | 26.29 | 26.66 | (3.15) | 4.06 *** |
Cigarette smoking (number of cigarettes smoked during the day) | 0 | 1.81 | (4.99) | 0 | 2.26 | (6.20) | −0.16 |
Lifetime use of cigarettes (pack-years) | 0 | 0.16 | (0.36) | 0 | 0.15 | (0.36) | −0.13 |
Coffee consumption (number of cubs during the day) | 2.0 | 1.93 | (1.40) | 2.0 | 1.61 | (1.34) | −2.04 * |
Alcohol consumption (frequency within a month) | 3 | 2.58 | (1.28) | 3.0 | 2.25 | (1.38) | −2.17 * |
Average sleep time during the night (hours) | 7.0 | 6.61 | (1.08) | 7.0 | 7.14 | (1.12) | 3.99 *** |
Physical activity (number of hours per week devoted to physical activity) | 3.0 | 3.22 | (2.49) | 3.0 | 2.83 | (2.54) | −1.49 |
OR | 95% CI | Wald Test | p-Value | |
---|---|---|---|---|
STAI * PSWQ | 1.00 | 1.00–1.01 | 11.14 | 0.001 |
BMI | 0.80 | 0.73–0.89 | 18.93 | <0.001 |
Average sleep time during the night | 0.69 | 0.56–0.86 | 11.50 | 0.001 |
Frequency of alcohol consumption | 1.30 | 1.08–1.58 | 7.37 | 0.007 |
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Wróbel-Knybel, P.; Rog, J.; Jalal, B.; Szewczyk, P.; Karakuła-Juchnowicz, H. Sleep Paralysis among Professional Firefighters and a Possible Association with PTSD—Online Survey-Based Study. Int. J. Environ. Res. Public Health 2021, 18, 9442. https://doi.org/10.3390/ijerph18189442
Wróbel-Knybel P, Rog J, Jalal B, Szewczyk P, Karakuła-Juchnowicz H. Sleep Paralysis among Professional Firefighters and a Possible Association with PTSD—Online Survey-Based Study. International Journal of Environmental Research and Public Health. 2021; 18(18):9442. https://doi.org/10.3390/ijerph18189442
Chicago/Turabian StyleWróbel-Knybel, Paulina, Joanna Rog, Baland Jalal, Paweł Szewczyk, and Hanna Karakuła-Juchnowicz. 2021. "Sleep Paralysis among Professional Firefighters and a Possible Association with PTSD—Online Survey-Based Study" International Journal of Environmental Research and Public Health 18, no. 18: 9442. https://doi.org/10.3390/ijerph18189442