Journal of Research in Medical and Dental Science
eISSN No. 2347-2367 pISSN No. 2347-2545

Research - (2019) Volume 7, Issue 2

Prevalence of Sleep Disorders and Sleep Deprivation Symptoms in Nurses and Paramedics: A Cross-sectional Analytic-descriptive Study

Nasrin Galehdar1, Abouzar Mohammadi2*, Shirin Hasanvand1, Fatemeh Goudarzi1 and Mohammad Gholami3

*Correspondence: Abouzar Mohammadi, Kashan University of Medical Sciences, Iran, Email:

Author info »


Background: The shift works cause sleep disorders and sleeps deprivation symptoms and noticeably affects human function. This study was designed to evaluate the prevalence of sleep disorders and sleep deprivation symptoms in nurses and paramedics (N & Ps).

Methods: In this descriptive-analytical study, 850 nurses and paramedical staff on shift work of Lorestan University of Medical Sciences were studied by simple sampling. The inclusion criteria were willingness to engage and work at the time of study. Data collection tools were demographic data and Pittsburgh Sleep Quality Index. After obtaining consent and completing the questionnaire, the data were analyzed by descriptive and analytic statistics using SPSS software version 16 via Kruskal-Wallis. Moreover, correlations were assessed using Spearman correlation.

Results: Current findings demonstrated that subjects with different shifts had sleep disorders in 98.8% of cases, while remains had 1 to 29 items of sleep ones. Disorders of initiating sleep and fatigue and weakness after waking up were observed in 67.5% and 64.9% of N & Ps, respectively. Subjects in 72.8% of cases preferred to stay at the bed in the morning and 28.9% had night terrors and Rapid Eye Movement behavior disorder. In terms of physical symptoms, fatigue and weakness had the maximum frequency (29.9%). Physical, mental, and emotional symptoms were observed in 96.7%, 94.8%, and 95.5%, respectively. The maximum frequency (38.4%) was correlated to inhibition of study.

Conclusion: Present findings demonstrated that subjects have sleep disorders and sleep deprivation symptoms in different severities. As for N & Ps are key individuals in the healthcare system and on the other hand are as potential patients in the future, paying special attention to them is necessary.


Nurses, Paramedics, Shifts, Sleep deprivation, Sleep disorders, Sleep


In the United States of America, at least 40 million people annually suffer from chronic, long-term sleep disorders, and an additional 20 million experience occasional sleeping problems. These disorders and the resulting sleep deprivation symptoms interfere with daily and social activities. Also, they account for an estimated $16 billion in medical costs annually, while the indirect costs due to lost productivity and other factors are probably much greater [1].

A sleep-restricted state called sleep deprivation can cause fatigue, daytime sleepiness, clumsiness, and weight loss or weight gain [2]; it adversely affects the brain and cognitive function [3-5]. However, in a subset of cases sleep deprivation can paradoxically lead to increased energy and alertness and enhanced mood; it has even been used to synchronize and consolidate circadian rhythms and as a treatment of depression [6-8]. Sleep deprivation noticeably affects human function, also the mood is more influenced by sleep deprivation than either cognitive or motor performance and that partial sleep deprivation has a more profound effect on functioning than either longterm or short-term sleep deprivation [9].

The negative effects of sleep deprivation on alertness and cognitive performance demonstrate declinations in the activity and function of the brain [10,11]. Also, sleep and circadian problems represent common non-motor features of Parkinson and Huntington diseases, and attention-deficit hyperactivity disorder [11,12].

Undesirable and night shift schedule results in sleepwake disturbances, alterations of sleep duration, chronic sleep restriction and excessive sleepiness, alterations in sleep architecture, sleep fragmentation, circadian rhythm disorders, and disruption and obstructive sleep apnea causing sleepiness during night shifts and reducing sleep length and quality in daytime sleep after the night shift. In its serious form, it is also called shift work sleep disorder [13,14].

Sleep disorders, physical and mental problems, job dissatisfaction, diminished performance at work and social isolation have been reported in some 88% of the American and Canadian shift-workers [15]. More recent studies; nevertheless, have demonstrated that the 12- hour shifts favored by many nurses and frequent overtime are associated with difficulties staying awake on duty, reduced sleep times, and nearly triple the risk of making an error [16-18].

Based on the 2006 Survey of Labour and Income Dynamics conducted by Statistics Canada, about 11% of employed Canadians work rotating shifts, while 6% work regular evenings and 2% work regular night shifts. The prevalence of both rotating and evening work is much higher among people under 30 than at elder ages. The number of women working evening, night, and especially, rotating shifts has dramatically increased over the last 10 years [19].

Poor sleep quality; misalignment of circadian rhythms, and subsequent sleepiness and sleep-related performance deficits among nurses and especially nightshift workers is a critical issue for the healthcare system. It not only leads to health problems of the nurses but also associates with lower work performance and a higher risk of medical errors, which may jeopardize the patient’s safety [20,21].

Hence, the present research was designed to evaluate the prevalence of sleep disorders and sleep deprivation symptoms in nurses and paramedics occupying in Khorramabad city training hospitals, Lorestan province, Iran in 2014.

Materials and Methods

A cross-sectional analytic-descriptive study was conducted from March 1st, 2014 to September 1st, 2014. The research population was all nurses and paramedical staff (n=1586) working in educational hospitals in Khorramabad.

The research sample included 936 people who were enrolled in current study by means of simple sampling method. Of the 936 subjects, 850 ones returned filled questionnaires (Its response rate is more than 90%).

After obtaining nurses’ and paramedics’ agreement to participate, the researchers introduced themselves to them, explained the trial’s objectives and assured the participants that their information would confidentially be kept, without mentioning their names. Then, necessary explanations were provided concerning the questionnaires. Afterward, consent forms were signed by the subjects.

Demographics (gender, age, marital status, degree, experience, and hours of time, occupational status, and wards) were collected and questionnaires were distributed among them (Table 1).

Demographics Number of subjects
Gender -
Male 248 (29.2%)
Female 602 (70.8%)
Age (years) -
21-30 376 (44.5%)
30-41 362 (42.6%)
41-50 100 (11.7%)
50-65 10 (1.2%)
Over 65 0 (0%)
Marital status  -
Single 262 (30.8%)
Married 588 (69.2%)
Groups  -
Nurse 532 (62.6%)
Nurse’s aide 110 (12.9%)
Surgical technologist 58 (6.8%)
Anaesthesiology technologist 40 (4.7%)
Midwife 66 (7.8%)
Radiology technologist 8 (1%)
Laboratory technologist 36 (4.2%)
Degree  -
Associate Degree 298 (35.1%)
Bachelor of Science 360 (42.4%)
Master of Science 192 (22.5%)
Experience (year)  -
1-10 538 (63.3%)
10-21 248 (29.2%)
21-30 64 (7.5%)
Hours of overtime (hours)  -
None 282 (32.3%)
1-50 166 (19.5%)
50-100 266 (31.3%)
100-150 110 (12.9%)
150-200 26 (3.1%)
Occupational status  -
Employed 486 (57.2%)
Contractual 192 (22.6%)
Subjects with overtime shifting 88 (10.4%)
Staffing plan 84 (9.8%)
Wards  -
Operating theatre 110 (12.9%)
Surgery 158 (18.6%)
ICU 45 (5.3%)
CCU 30 (3.5%)
NICU 41 (4.8%)
Medicine 215 (25.3%)
Internal 207 (24.4%)
Radiology 8 (1%)
Laboratory 36 (4.2%)

Table 1: Demographics of the subjects

Sleep disorders and sleep deprivation symptoms were measured by the Pittsburgh Sleep Quality Index (PSQI). The PSQI is a self-report basis on a 5-point Likert scale assessing sleep quality and disturbances over a 1-month time interval. It differentiates “poor” from “good” sleep by measuring 7 areas: subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medication, and daytime dysfunction over the last month. Scoring of answers is based on a 0 to 4 scale; whereby “3”, reflects the negative extreme on the Likert Scale. It ranges 0 to 21 scores. A global sum of “6” or greater indicates a “poor” sleeper. It has internal consistency and a reliability coefficient (Cronbach’s alpha) of 0.83 for its 7 components [22].

The validity and reliability of the PSQI was previously confirmed by several studies [23-25]. Inclusion criteria were willingness to engage, not-taking anxiolytic and narcotic medications, not-taking alcohol and caffeine, having no apparent physical and mental disorder(s), occupying in a current shift for at least 1 month, and absence of a critical condition in recent 1 month.

The aforementioned questionnaires were distributed among selected samples and filled out with the help of researchers. Then, documented data were extracted. The findings obtained were finally analyzed by descriptive and analytic statistics using SPSS software version 16 via Kruskal-Wallis and Spearman correlation.

Ethical considerations

The protocol was designed in accordance with the ethical principles of the Helsinki Declaration [26]. Lorestan University of Medical Sciences and Health Services’ Ethics Committee considered the project to fall outside its mandate. The nurses and paramedics were given a verbal lecture and written information about the goals and approach of the project, and then they declared to help the researchers to perform the study.



Table 1 shows the demographic data of the subjects studied.

Sleep disorders

Based on current findings, only 20.9% of subjects did not have a disorder in initiating sleep. The maximum disorder in initiating sleep after half an hour was observed in 67.5% of the subjects (Table 2). The frequency of subjects with 1, 2, and 3 disorder(s) was 28.9%, 42.4%, and 7.8%, respectively. The maximum frequency (87.1%) of sleep maintenance disorder was concerned fatigue during the day. Totally, only 2.4% of the subjects did not have any problem in terms of sleep maintenance.

Sleep disorders Questions Positive reply Negative reply
Disorder in initiating sleep Does it take more than half an hour to sleep? 574 (67.5%) 276 (32.5%)
Do aggressive thoughts come to your mind when you are trying to sleep? 476 (56%) 374 (44%)
Do you sleep better when you are out of your bed? 118 (13.9%) 732 (86.1%)
Disorder in maintaining sleep Do you frequently wake up in the middle of the night or early morning? 434 (51.1%) 416 (48.9%)
Do you lately go to bed after waking up at the night? 498 (58.6%) 352 (41.4%)
Do you feel fatigue during the day? 740 (87.1%) 110 (12.9%)
Do you feel apnoea when you are asleep? 144 (16.9%) 706 (83.1%)
Do you wake up with mild noises? 600 (70.6%) 250 (29.4%)
Do you snore when you are asleep? 170 (20.0%) 680 (80%)
Do you wake up by muscular twitching? 386 (45.4%) 464 (54.6%)
Disorder in waking up Do you wake up 2 to 3 hours earlier than normal time? 320 (37.6%) 530 (62.4%)
Do you feel fatigue and weakness after waking up? 552 (64.9%) 298 (35.1%)
Do you feel provocation and absence of concentration during the day? 478 (55.5%) 372 (44.5%)
Excessive sleepiness Are you attacked by sleep irresistible attacks during the day? 320 (37.6%) 530 (62.4%)
Do you nap during the day? 384 (45.2%) 466 (54.8%)
Do you feel episodes of disorientation or confusion and movement disorder? 218 (25.6%) 632 (74.4%)
Do you want to stay in bed more than normal time in the morning? 618 (72.7%) 232 (27.3%)
Do you feel drowsiness/sleepiness during the day? 496 (58.4%) 354 (41.6%)
Parasomnia Do you have night terrors and rapid eye movement behavior disorder? 246 (28.9%) 604 (71.1%)
Do you feel restless leg syndrome before and after waking up? 180 (21.2%) 670 (78.8%)
Do you gnash when you are asleep? 82 (9.6%) 768 (90.4%)
Do you walk when you are asleep? 24 (2.8%) 826 (97.2%)
Do you talk when you are asleep? 156 (18.4%) 694 (81.6%)

Table 2: Absolute and relative frequency distribution of sleep disorders in N & Ps

The maximum frequency (64.9%) was for weakness and fatigue after waking up. The frequency of subjects with 1, 2, and 3 disorder(s) in waking up stage was 25.2%, 36%, and 20.7%, respectively. The excessive sleepiness was observed in 72.8% of N & Ps with 5 disorders. Moreover, the most parasomnia (28.9%) was indicated as night terrors and Rapid Eye Movement behavior disorder. In 98.8% of the subjects, 1 to 29 items of sleep disorders were observed. In this between, the maximum frequency was concerning who recorded 9 scores (of 21) of sleep disorders (Table 3).

Sleep disorders score Number of subjects with sleep disorders
None (without problem) 10 (1.2%)
Mild (scores between 1-7) 286 (33.6%)
Moderate (scores between 7-14) 418 (49.2%)
Severe (scores between 14-21) 136 (16%)

Table 3: Absolute and relative frequency distribution in N & Ps according to a total score of sleep disorders

Sleep deprivation symptoms

Sleep deprivation symptoms are presented in Table 4. In terms of physical symptoms, the maximum frequency belonged to weakness and fatigue, and headache with the values of 29.9% and 24.5%, respectively. In total, 96.7% of subjects with noticeable problems recorded scores in the range of 1 to 40. Generally, the score 26 was the mode for sleep deprivation symptoms. The maximum mental symptoms were related to indisposition feeling, and aggression and irritability with the frequency of 24.7% and 23.8%, respectively. Totally, 24 scores were allocated to mental symptoms; it showed that 94.8% of subjects recorded scores in the range of 1 to 24. Moreover, 95.5% of them with emotional symptoms recorded scores in the range of 1 to 36. The maximum frequency was related to inhibition of study and fun with the amounts of 38.4% and 36.2%, respectively. There were sleep deprivation symptoms in 97.9% with the scores from 2 to 99.

Symptoms Problems  Level
Too much Much Low Very low I did not have Total
Physical symptoms Sleep disorder 23.5 27.3 22.1 11.8 15.3 100
Malnutrition 22.6 27.8 21.4 12.5 15.8 100
Impaired vision 10.6 13.6 21.9 15.1 38.8 100
Decreased libido 11.1 10.1 13.9 8.5 56.5 100
Tachycardia 8 23.5 23.8 10.1 34.6 100
Shivering 4.9 10.6 20.7 14.6 49.2 100
Headache 24.5 30.8 21.2 10.6 12.9 100
Decreased vigilance 13.2 22.8 29.4 16.2 18.4 100
Frequent naps during the day 16.5 18.1 25.6 14.6 25.2 100
Frequent yawning during the day 19.1 25.2 21.9 16 17.9 100
Mental and emotional symptoms Aggression and irritability 23.8 24 25.2 12.9 14.1 100
Loss of affection and love 14.8 20 28.2 12.9 24 100
Loss of confidence 11.8 15.8 26.6 14.6 31.3 100
Reduced tolerance to problems 18.6 26.8 22.4 12.2 20 100
Impaired memory and concentration 15.8 24.7 23.5 15.8 20.2 100
Impairment of tasks to the spouse and/or family 15.7 24.2 18.4 12.9 28.7 100
Impairment of tasks to the children and/or relatives 16.9 21.6 20 13.5 28.9 100
Inhibition of fun 36.2 31.8 12.9 6.8 12.2 100
Inhibition of study 38.4 33.9 12 6.1 9.6 100
Social isolation 13.6 19.3 19.3 13.4 34.4 100

Table 4: Relative frequency distribution of sleep deprivation symptoms in N & Ps

Findings analyzed based on Spearman correlation

Correlations based on Spearman ratio (r) among demographics and sleep deprivation symptoms are presented in Table 5. Correlations between experience with sleep maintenance disorder and physical symptoms were positive and significant (0. 20 and 0.12, respectively). The positive and significant correlation was obtained between hours of overtime with excessive sleepiness and total sleep disorders (0.11 and 0.10, respectively).

Variables Experience Age (years) Hours of overtime Disorder in initiating sleep Disorder in maintaining sleep Disorder in waking up Excessive sleepiness Parasomnia Total sleep disorders Physical symptoms Mental symptoms Emotional symptoms
Experience 1 0.93 ns ns 0.2 ns ns ns 0.1 0.12 ns ns
Age (years) 0.93 1 ns ns 0.2 ns ns ns ns ns ns ns
Hours of overtime ns ns 1 ns ns ns 0.1 ns 0.1 ns ns ns
Disorder in initiating sleep ns ns ns 1 0.39 0.32 0.3 0.28 0.58 0.38 0.28 0.35
Disorder in maintaining sleep 0.2 0.2 ns 0.39 1 0.54 0.38 0.41 0.79 0.48 0.37 0.4
Disorder in waking up ns ns ns 0.32 0.54 1 0.44 0.37 0.72 0.47 0.44 0.42
Excessive sleepiness ns ns 0.11 0.3 0.38 0.44 1 0.42 0.73 0.44 0.45 0.47
Parasomnia ns ns ns 0.28 0.41 0.37 0.42 1 0.64 0.5 0.47 0.44
Total sleep disorders 0.1 ns 0.1 0.58 0.79 0.72 0.73 0.64 1 0.62 0.56 0.57
Physical symptoms 0.12 ns ns 0.38 0.48 0.47 0.44 0.5 0.62 1 0.77 0.73
Mental symptoms ns ns ns 0.28 0.37 0.44 0.45 0.47 0.56 0.77 1 0.79
Emotional symptoms ns ns ns 0.35 0.4 0.42 0.47 0.44 0.57 0.73 0.79 1

Table 5: Spearman correlations between demographics and sleep deprivation symptoms

Findings analyzed based on the Kruskal-Wallis test

Cora relations based on the Kruskal-Wallis test (λ2) among demographics and sleep deprivation symptoms are shown in Table 6. Correlation between degree of study and sleep deprivation symptoms were ranged from 7 to 26.1 for total sleep disorders and emotional symptoms, respectively. A significant correlation was obtained between occupational status with initiating sleep, excessive sleepiness, and mental, emotional, physical, and total symptoms of sleep deprivation being 19.4, 13, 16.2, 26.6, 16.4, and 21.8, respectively. Concerning wards wherein subjects occupied, correlations were ranged from 23.3 to 62.3 for initiating sleep and emotional symptoms of sleep deprivation.

Variables Disorder in initiating sleep Excessive sleepiness Total Sleep disorders Physical symptoms Mental symptoms Emotional symptoms Total sleep deprivation symptoms Parasomnia Disorder in maintaining sleep
Degree 0.017 0.025 0.03 0.004 0.001 0.001 0.001 ns ns
Shift 0.02 0.009 ns ns 0.029 0.019 0.04 ns ns
Occupational status 0.001 0.023 ns 0.006 0.006 0.001 0.001 ns ns
Wards 0.016 0.004 0.013 0.001 0.001 0.001 0.001 0.001 ns
Employing conditions ns ns 0.05 0.007 ns ns ns 0.014 0.01

Table 6: Correlations between demographics with sleep deprivation symptoms based on Kruskal-Wallis test

Study Limitations

Study limitation includes cultural characteristics of research sample, voluntary entry to study and selfdeclaration.


Based on current findings, misalignment between shift schedule and hours of sleep caused disorders in sleep initiation and maintenance of 67.5% and 87.1% of the shift-workers. Present findings were consistent with the study of Gamaldo et al., Jensen et al., and Shiffer et al. They reported that being of misalignment between the sleep pattern and the desired sleep schedule causing difficulty in initiating sleep, maintaining sleep, and/or experiencing poor quality sleep predisposing people to insomnia or excessive sleepiness [27-29]. Current statistics of the subjects with the disorder in sleep maintenance was noticeably significant. Vallieres et al. reported that difficulties in falling and maintaining sleep experienced by shift workers exacerbates certain physical and mental problems and impairs their life quality. The report was compatible with current findings [30].

Present findings showed that some two-thirds of the subjects with circadian sleep disorders suffered from fatigue. Saleh et al. reported similar findings [31]. Other studies indicated that sleep disorders and sleep deprivation in night-shift workers might cause high levels of fatigue [28,29]. Ferreira et al. In their study showed that Subjects with excessive sleepiness in 72.8% of cases showed disorders such as sleep irresistible attacks, naps during the day, episodes of disorientation or confusion and movement disorder, staying at bed more than normal time, and drowsiness [32]. Inconsistency, Boivin et al. reported that vigilance, performance, health, and safety of shift-workers are significantly influenced by excessive sleepiness [15]. Findings obtained showed that undesirable shift schedule of N & Ps contributes to sleep disorders and following work impairment. Congruently, Swanson et al. reported that sleep disorders considerably increases the possibility of negative outcomes of shiftworkers [33]. In the current study, the frequency of physical, mental, and emotional symptoms of sleep deprivation was remarkably significant being 96.7%, 94.8%, and 95.5%, respectively. Inconsistent with the several reports, obtained findings demonstrated that undesirable shift schedule affect circadian rhythms [34] causing mentioned symptoms, which may lead to occupational error [35], leave them at higher risk of daily and social aspects [36], and have a negative effect on attention [37], daily performance [38], and working memory [39].

Furthermore, several reports demonstrated that sleep deprivation, alteration, and disruption of the circadian rhythms influence physical, mental and emotional aspects and have a deleterious effect on fine motor coordination in healthcare providers and may differentially impair processing of more-detailed visual information [40-44]. Conversely, Scherer et al. indicated that sleep deprivation does not affect dynamic visual acuity [45]. Also, no significant decrease was shown in the performance of sleep-deprived healthcare providers in the study of O’Brien et al. [46].

Current findings showed a direct association between hours of overtime with excessive sleepiness. In the agreement, Pikovsky et al. and van Leeuwen et al. reported that hours of overtime among healthcare providers are associated with increased sleepiness significantly leads to excessive sleepiness [47,48]. Scott et al. reported a direct correlation between hours of overtime with decreased vigilance and increased risk of errors in nurses [18]. Moreover, over time shifting adversely influences the health and safety of shiftworkers [49].

In the current study, the correlation between excessive sleepiness and gender was significant. Similarly, Fatani et al. reported a significant correlation between excessive sleepiness and gender in shift-workers with the undesirable sleep-wake schedule [50]. In contrast to the present study, they reported that being married in sleepdeprived shift-workers is a protective factor against excessive sleepiness. In the current findings, the correlation was significant between occupational status with sleep disorders and symptoms of sleep deprivation.

There were no reports, to our knowledge, to compare with current findings in terms of the degree of study and occupational status with sleep deprivation symptoms. Only verified report was available from the Centres for Disease Control and Prevention in terms of sleep duration among shift-workers indicated a high prevalence of short sleep duration in healthcare providers with night shifts [51]. In conclusion, decreased performance and vigilance in nurses and paramedics with sleep deprivation symptoms may result in decreased safety and health of the patients.


Current findings indicated that nurses and paramedics have disorders in initiating and maintaining sleep and physical, mental, and emotional symptoms of sleep deprivation in differently impressive severities. Also, there were significant correlations between gender, marital status, experience, and hours of overtime with sleep disorders and symptoms of sleep deprivation. As for nurses and paramedics are key individuals in the healthcare system, and unfortunately as potential patients in the future mainly owing to undesirable and heavy shifts, paying special attention to them is necessary.


As for heavy shifts of nurses and paramedics, we suggest favorable and desirable shift schedule for them also investigating their sleep quality in regular intervals, arranging favorable shift schedule as they can do their daily activities and do meditation and exercises to get more comfortability and more energy.


This research project (No: 948) was sponsored by Deputy of Research and Technology of Lorestan University of Medical Sciences. Authors appreciate nurses and paramedics of teaching hospitals affiliated to Lorestan University of Medical Sciences who contributed to the research project.

Authors Contributions

NG: designed, collected and analyzed data; AM: written the manuscript; FG: data collection; MG: data collection; SH: data analysis

Conflict of Interest

The authors declare that there is no conflict of interest regarding the publication of this article.


Author Info

Nasrin Galehdar1, Abouzar Mohammadi2*, Shirin Hasanvand1, Fatemeh Goudarzi1 and Mohammad Gholami3

1Social Determinants of Health Research Center, Lorestan University of Medical Sciences, Khorramabad, Iran
2Kashan University of Medical Sciences, Kashan, Iran
3School of Nursing and Midwifery, Lorestan University of Medical Sciences, Khorramabad, Iran

Citation: Nasrin Galehdar, Abouzar Mohammadi, Shirin Hasanvand, Fateme Goudarzi, Mohammad Gholami, Prevalence of sleep disorders and sleep deprivation symptoms in nurses and paramedics: A cross-sectional analytic-descriptive study, J Res Med Dent Sci, 2019, 7(2): 11-19.

Received Date: Jan 07, 2019 / Accepted Date: Mar 01, 2019 /