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ORIGINAL ARTICLE
Year : 2022  |  Volume : 26  |  Issue : 1  |  Page : 3-8
 

Evaluation of the relationship between occupational accidents and obstructive sleep apnea risk among employees of a university hospital


1 Department of Occupational Health and Safety, Eskisehir Osmangazi University, Medical Faculty, Eskişehir, Turkey
2 Department of Emergency Medicine, Eskisehir Osmangazi University, Medical Faculty, Eskişehir, Turkey
3 Department of Public Health, Eskisehir Osmangazi University, Medical Faculty, Eskişehir, Turkey

Date of Submission29-Dec-2021
Date of Decision17-Jan-2022
Date of Acceptance05-Feb-2022
Date of Web Publication7-Apr-2022

Correspondence Address:
Dr. Halime Kucuk
Department of Occupational Health and Safety, Eskisehir Osmangazi University, Medical Faculty, 26040 Eskisehir
Turkey
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ijoem.ijoem_361_21

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  Abstract 


Context: Occupational accidents are still one of the important causes of morbidity and mortality. Sleep apnea is a significant risk factor for occupational accidents in hospitals. Aims: To determine the frequency of occupational accidents and their relationship with the risk of obstructive sleep apnea (OSAS). Settings and Design: Cross-sectional study in a hospital setting. Methods and Material: This study was conducted on 331 hospital workers between 2019-2020. Accidents from the Social Security Institution records were used. The risk of OSAS was evaluated with Berlin Survey, daytime sleepiness with Epworth Sleepiness Scale, sleep quality with Pittsburg Sleep Quality Scale. Statistical Analysis: The Chi-square test was used for analysis; P < 0.05 was accepted as a statistical significance value. Results: Of the participants, 231 (69.8%) were female. Their ages ranged between 19 and 55; the mean age was 33.8 ± 8.0 years. The frequency of occupational accidents was 8.8%, 51.4% had a high risk of OSAS, 80.4% had high daytime sleepiness, and 53.5% had poor sleep quality. Conclusion: The study group had a high risk of sleep disorders. No relationship was found between sleep disorders and occupational accidents. More comprehensive studies are needed to clarify this relationship.


Keywords: Hospital workers, occupational accident, sleep apnea, sleep disorders, sleep quality


How to cite this article:
Kucuk H, Acar N, Ünsal A, Kılınç A. Evaluation of the relationship between occupational accidents and obstructive sleep apnea risk among employees of a university hospital. Indian J Occup Environ Med 2022;26:3-8

How to cite this URL:
Kucuk H, Acar N, Ünsal A, Kılınç A. Evaluation of the relationship between occupational accidents and obstructive sleep apnea risk among employees of a university hospital. Indian J Occup Environ Med [serial online] 2022 [cited 2022 Aug 8];26:3-8. Available from: https://www.ijoem.com/text.asp?2022/26/1/3/342675





  Introduction Top


Occupational accidents are fundamental problems of working life in the world including Turkey. Although various definitions have been formed about work accidents, the exact meaning is expressed in different sentences in the definitions. International Labor Organization describes an occupational accident as “an unexpected and unplanned event that causes specific damage or injury”.[1] While in Turkey, the Work Accident Occupational Disease Notification System of the Social Security Institution defines an occupational accident as the cases specified in the 13th Article of the Social Insurance and General Health Insurance Law No. 5510. According to the law, events occurring: a) while the insured is at the workplace, b) due to the work carried by the employer, c) when the insured working under an employer is sent to another place outside the workplace without performing their primary job, d) during the time allotted for the insured woman to breastfeed her child, e) during the insured's travel to and from the place where the work is carried out with a vehicle provided by the employer, and f) while the insured is working independently on their behalf are considered as occupational accidents.[2]

An essential portion of workplace accidents has been attributed to sleep disorders.[3] It is known that there are about 85 types of sleep disorders.[4] One of these sleep orders, called Obstructive Sleep Apnea Syndrome (OSAS), causes a severe decrease in daytime alertness, impaired concentration, loss of motor coordination, and decreased reflexes. OSAS is a condition that occurs as a result of complete (apnea) or partial (hypopnea) obstruction of the upper respiratory tract during sleep and is characterized by nighttime desaturation and excessive daytime sleepiness.[5] The most prominent clinical features of OSAS are snoring, witnessed apnea, and excessive daytime sleepiness and cardiopulmonary findings such as insomnia, morning headaches, restlessness, restless legs syndrome, chest pain, palpitations, and also rhythm disturbances can also be observed.[6] It has been reported that the prevalence of respiratory-related sleep disorders is 13.7% in Turkey.[7] It is estimated that 82% of men and 93% of women with probable OSAS are not yet diagnosed because individuals with sleep disorders are not aware of their condition.[8] A large-scale study has been conducted by Azagra-Calero et al.[9] to determine the prevalence of the disease, where it is was found to be more common in middle-aged individuals, and its frequency was observed as 2% in women and 4% in men.

In order to prevent occupational accidents, it is necessary to determine the leading causes of accidents. In a study, in which the European Major Accident Reporting System records were analyzed, it was reported that 70-96% of accidents belonging to different sectors were caused by unsafe human behaviors.[10] It has been reported that 70% of occupational accidents occurring in more than 1,000 hospitals are due to the human factor.[11] In order to prevent accidents, it is imperative to investigate the root causes of these dangerous human movements. In a study by Uehli et al.,[3] it was reported that 13% of occupational accidents were related to sleep problems.

This study aimed to determine the frequency of occupational accidents and its relationship with the risk of obstructive sleep apnea among the employees of a university hospital.


  Materials and Methods Top


This cross-sectional study was conducted on permanent workers (4D) at Eskişehir Osmangazi University Medical Faculty Hospital between 18.12.2019 and 20.09.2020.

In order to conduct the study, approval was obtained from the Non-Invasive Clinical Research Ethics Committee of Eskişehir Osmangazi University, dated 11.12.2018 and numbered 20. In order to collect data in the study, necessary permissions were obtained from the hospital management.

A questionnaire form was prepared in the study using the literature as a data collection tool. The questionnaire consists of some sociodemographic characteristics of the employees, work accident history, Berlin questionnaire, Epworth Sleepiness Scale, and Pittsburg Sleep Quality Scale questions.

The research universe is a total of 623 employees working in the permanent worker staff group in Eskişehir Osmangazi University Medical Faculty Hospital. In the study, it was aimed to reach the whole universe, not taking a sample. The study was conducted on an entirely voluntary basis, and those who did not accept to participate in the study, who used drugs due to sleep disorders and who answered the survey questions incompletely were not included in the study.

Those who formed the study group were visited in the units they worked in the hospital and were informed about the subject and purpose of the study. Written informed consent was obtained from those who agreed to participate in the study. Afterwards, the prepared questionnaire forms were filled by the participants under observation. A total of 331 people (53.1%) who agreed to participate constituted the study group.

In this study, the cases reported through the “Work Accident Occupational Disease Notification System” of the Social Security Institution (The cases specified in the 13th Article of the Social Insurance and General Health Insurance Law No. 5510) are accepted as occupational accidents. The most common type of occupational accident recorded in our study was needle stick injuries. Other notable accidents were falling, cuts in hand, and chemical contamination.

The gold standard method in diagnosing OSASis polysomnography. Apart from the questionnaires developed by sleep centers, there are also internationally valid questionnaires. One of them is the Berlin Survey. This study evaluated the risk of OSAS using the Berlin questionnaire. The Berlin questionnaire, which is a simple and valuable tool for screening the risk of OSAS in the general population, was developed by Sharma et al. in 2006,[12] and its validity and reliability study in Turkey was performed by Yüceege et al.[13] The Berlin questionnaire consists of 10 questions belonging to three categories questioning the presence of snoring, daytime sleepiness, obesity, or hypertension. Each category is evaluated within itself, and two or more categories supporting the existence of symptoms questioned are considered high risk for OSAS.

In this study, Epworth Sleepiness Scale was used to evaluate the daytime sleepiness of individuals. The Epworth Sleepiness Scale, the most common method used to rate sleepiness in sleep disorders research, was developed by Johns.[14] in 1991, and its validity and reliability study in Turkey was carried out by Izci et al. in 2008.[15] The scale consists of 8 questions, and each question is scored between 0-3. The scoring method of all questions is the same, 0 if there is no probability of falling asleep, 1 if there is a low probability of falling asleep, 2 if it is a medium probability, and 3 if it is a high probability. The scores that can be obtained from the scale range from 0-24, and 10 points and above are considered to have high daytime sleepiness.

The employees' sleep quality was evaluated with the Pittsburg Sleep Quality Scale (PSQS). PSQS is a scale that considers the individual's status in the last four weeks. The scale was developed by Buysse et al. in 1989,[16] and its validity and reliability study in Turkey was conducted in 1996 by Ağargün et al.[17] The scale consists of 24 questions. The total score obtained from the scale varies between 0-21, and as the score increases, sleep quality decreases. If the total score obtained from PSQS is 5 and above, the sleep quality is evaluated as bad.

The obtained data were evaluated in SPSS (version 15.0) Statistical Package Program. The Chi-square test was used for analysis. P < 0.05 was accepted as the statistical significance value.


  Results Top


About 100 (30.2%) of the study group were male, and 231 (69.8%) were female. Participants' ages ranged from 19 to 55, with a mean of 33.8 ± 8.0 years. In this study, the frequency of occupational accidents was 8.8% (n = 29). The distribution of those with and without a work accident history in the study group according to some sociodemographic characteristics is presented in [Table 1].
Table 1: Distribution of those with and without occupational accident history in the study group according to some sociodemographic characteristics

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In this study, the number of those with a high risk of Obstructive Sleep Apnea was 170 (51.4%), the number of those with high Daytime Sleepiness was 266 (80.4%), and the number of those with poor Sleep Quality was 177 (53.5%). [Table 2] presents the distribution of those with and without a history of occupational accidents in the study group according to the results of some non-Polysomnography (PSG) diagnostic methods.
Table 2: Distribution of the study group with and without an occupational accident history according to the results of some non-PSG diagnostic methods

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The study determined that the sleep quality of those with a high risk of Obstructive Sleep Apnea and those with a high level of Daytime Sleepiness were worse (P < 0.05 for each). The distribution of those with poor and good sleep quality according to the risk of Obstructive Sleep Apnea and Daytime Sleepiness is presented in [Table 3].
Table 3: Distribution of patients with poor and good Sleep Quality in the study group according to the risk of Obstructive Sleep Apnea and Daytime Sleepiness

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  Discussion Top


It is a known fact that many psychosocial, chemical, physical, mechanical and biological risk factors in hospitals have a significant share in occupational accidents.[18] Workforce loss and economic losses occur due to permanent damage, disability and the development of some mental disorders in health workers who are exposed to work accidents. In addition, there are setbacks in patient care.[19] In this context, in this study examining the occupational accidents seen in hospital workers, the occupational accident frequency rate was determined as 8.8%. In 2017 records to the United States Department of Labor's Occupational Safety and Health Administration (OSHA), the frequency of non-fatal occupational accidents in hospitals is 5.1%.[20] In a study examining occupational accidents among hospital workers in Turkey, the frequency of occupational accidents with sharp objects was reported as 18.2%.[21] The different results reported in studies on the frequency of occupational accidents may be because occupational accidents are based on self-report, and the memory factor is influential.

Sharp-piercing objects and chemicals are among the important risk factors for occupational accidents in hospitals. It is known that nurses and cleaning staff who constantly use such materials due to their work are more frequently exposed to work accidents. This study observed that nurses and cleaning staff were exposed to occupational accidents more frequently than office workers and technicians. In a study by Martins et al.[22] on healthcare workers, it was reported that the frequency of occupational accidents was higher among nurses. In a study by Çiçek-Şentürk et al.,[23] it was reported that trainee nurses and cleaning staff had the most work accidents. In a study conducted among health workers in Ankara, it was reported that there was no difference between occupational groups in terms of occupational accident frequency.[24] These different results reported in various studies may be due to the difference in the inclusiveness of the training programs organized by the hospitals' occupational health and safety units.

This study found that the occupational accident frequency rate among the office staff was lower than that of the emergency room-operating room-intensive care, surgical service, and internal service-polyclinic employees. Similarly, in a study by Camacho-Ortiz et al.,[25] examining occupational accidents occurring in a hospital in Mexico for five years, the most frequent accidents were reported in the emergency department, internal medicine service, surgical service, and operating rooms. Emergency services, internal and surgical services, and operating rooms, which have many risks such as needle prick, scalpel cut, slip and fall, etc., are riskier in terms of occupational accidents than offices where office work is done.

It is known that shift work, which causes circadian rhythm disorders, is an important risk factor for occupational accidents for all healthcare professionals, especially in hospitals.[26] In our study, as expected, the frequency of occupational accidents was higher among hospital personnel working in shifts. Similar results have been reported in the literature.[27],[28] In a systematic review by Zhao et al.[29] on the effects of shift work among healthcare workers, it was reported that shift work increased occupational accidents, but a causal relationship could not be established due to methodological limitations.

One of the important causes of Daytime Sleepiness is Obstructive Sleep Apnea. Although obstructive sleep apnea is preventable, it is a significant risk factor for workplace accidents because it is common in the community and cannot be adequately diagnosed.[30] However, in this study, no relationship was found between Obstructive Sleep Apnea and Daytime Sleepiness and the frequency of occupational accidents. In a similar study by Jurado-Gámez et al.,[31] it was reported that there was no difference in the incidence of occupational accidents between those with and without Obstructive Sleep Apnea. The differences between the methods used to detect the presence of Obstructive Sleep Apnea may explain this result. Those with a high risk of Obstructive Sleep Apnea and Daytime Sleepiness can have severe occupational accidents that can cause death. The absence of the expected relationship between obstructive sleep apnea and daytime sleepiness and the frequency of accidents in our study can be explained by the fact that most of the occupational accidents are needle sticks, that is, the accidents are very mild.

There is a very complex relationship between work done and sleep quality. Working conditions at workplaces and especially the stress caused by psychosocial risk factors lead to deterioration of sleep quality. As a result of deteriorated sleep quality, productivity at work decreases and work accidents become more common.[32] In this study, the relationship between sleep quality and the frequency of occupational accidents was examined, but no relationship was found. In addition, it was found that sleep quality was better in those with low risk of Obstructive Sleep Apnea, and Daytime Sleepiness was higher in those with poor sleep quality. In a study by Chien et al.[33] on female nurses, it was reported that sleep quality was found to be lower in patients with sleep apnea frequency over 15 per hour. It has been reported that there is no relationship between sleepiness and sleep quality and that there is no difference in sleep quality and daytime sleepiness between those with normal and high hourly sleep apnea frequency.[34] This different result may have been reported because only those with Obstructive Sleep Apnea were included in the study and it was conducted in a small study group.

Limitations

Due to the study's cross-sectional nature, a causal relationship could not be established from the findings. Since the study was conducted during the early stages of the pandemic, voluntary participation has suffered; thus, we were able to reach only 53% of the research universe. Using a questionnaire form to determine the presence of occupational accidents may have resulted in a memory bias.


  Conclusion and Recommendations Top


Occupational accidents are an important occupational health and safety problem among hospital workers. It was determined that those in the study group had a high risk of sleep disorders. Sleep quality has been observed to be poor in those with sleep disorders. A proactive approach is essential in the prevention of occupational accidents. Within the scope of determining the risks, possible sleep problems should be considered as a danger for occupational accidents, especially in shift-working sectors. Evaluating all employees in terms of sleep problems through screenings within the scope of periodic health examinations and/or risk assessments of employees and directing suspicious cases to treatment will effectively reduce occupational accidents. More comprehensive studies are needed to reveal the relationship between sleep disorders and occupational accidents.

Acknowledgments

We appreciate the cooperation of the directorate of Eskişehir Osmangazi University Medical Faculty Hospital.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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    Tables

  [Table 1], [Table 2], [Table 3]



 

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