Qom University of Medical Sciences Journal

Introduction
Occupational stress is the second work-related disease after skeletal diseases. It occurs when the demands of a profession are more than people’s abilities. Nurses are the part of largest profession in the healthcare system. There are more than 19 million nurses worldwide, which make up about 70% of the healthcare team. The emergence of new unknown diseases such as the novel coronavirus disease (COVID-19) caused serious threats to the safety of nurses and created physical health problems, social isolation, and psychological problems such as depression, anxiety and stress. Psychological problems of nurses due to increased workload, being away from family during the quarantine period, seeing many patient deaths, decreasing social interactions, sexual needs, changes in work life style, and occupational stress make them vulnerable. In different studies, different factors have been reported that predict nurses’ occupational stress. For example, Barzegar (2021) and Amiri (2021) suggested demographic and occupational factors, and in Dehghani’s study, occupational stress was related to nurses’ psychological health. The studies conducted during the COVID-19 pandemic on occupational stress and its related factors are mostly descriptive studies. Conducting a review study in this field can help clarify and integrate the results of these studies. Therefore, the present study aims to review the existing studies on nurses’ occupational stress and its related factors during the COVID-19 pandemic.
Methods
This is a systematic review. A search was conducted in national and international databases such as Web of Science, Magiran, IranDoc, IranMedex, SID, Scopus, Cochran, Google Scholar, and PubMed for the related studies using keywords job stress, nurse, occupational stress, COVID-19 in Persian and English using the AND operator without time limit. The titles and abstracts of the found articles were first examined. After the approval based on the inclusion criteria, their full texts were read by one of the researchers. Descriptive, analytical and interventional articles that were conducted on nurses were selected. Initial search yielded 3860 articles. By removing duplicates, articles with no available full texts, letters to the editor, and short reports, 15 eligible articles were selected for the review. The critical appraisal skills programme checklist was used to check their quality. In order to extract the data, a data extraction form was used, which included sections such as the authors’ names, year of publication, study objectives, type of study, sample size, data collection method, and results. After completing this form, they were analyzed, summarized and finally reported.
Results
In most of the studies, the occupational stress of nurses during the COVID-19 pandemic was at a high level. The highest area was related to the demand area and the lowest was related to changes. Occupational stress had a significant positive relationship with age, gender, work experience, physical activity, employment status, position, workload, mental health, fear of COVID-19, working with short rest interval, psychological detachment, neuroticism, extroversion, job burnout, desire to quit servicing, managerial, individual, physical, patient care and interpersonal related factors and had a significant negative relationship with work engagement, low rest, job-related affective well-being, organizational commitment, productivity, organizational climate, and knowledge.
Discussion
Based on the findings of the present study, the occupational stress of nurses during the COVID-19 pandemic was at a high level. This is consistent with the results of Qeshlaghi’s study (2017) and Aoki’s study (2013) in Northern Ireland. A high level of occupational stress is expected due to the nature of nursing profession and facing an unknown new disease. During the pandemic, conflicts with doctors, insufficient supplies, lack of effective communication with colleagues and managers, discrimination, high workload, worry about treatment, facing the death of patients, and the stress of facing the patient’s family are among the common occupational stressors in nurses.
Demographic, occupational, and mental factors and quitting job have a significant positive relationship with occupational stress of nurses, while low rest, job-related affective well-being, organizational commitment, productivity, organizational climate have a significant negative relationship with their occupational stress. One of the weaknesses of this study is the removal of qualitative and experimental studies from the review; therefore, researchers are recommended to include qualitative and experimental studies in their review studies. It is also recommended to form committees to monitor nurses’ occupational stress in hospitals.

Ethical Considerations
Compliance with ethical guidelines
This a review study. No experiments on human or animal samples were conducted. Hence, there was no need for ethical considerations.
Funding
This research did not receive any grant from funding agencies in the public, commercial, or non-profit sectors.
Authors contributions
The authors equally contributed to preparing this article.
Conflicts of interest
The authors declare no conflict of interest.