==== Front Medicine (Baltimore)Medicine (Baltimore)MEDIMedicine0025-79741536-5964Wolters Kluwer Health 30075521MD-D-17-0814710.1097/MD.0000000000011543115436600Research ArticleObservational StudyAssociations between occupational stress and demographic characteristics in petroleum workers in the Xinjiang arid desert Jiang Ting MasterTao Ning PhDShi Lingyun MasterNing Li PhDLiu Jiwen PhD∗Tarantino. Giovanni Department of Public Health, Xinjiang Medical University, Urumqi, China; Department of Joint surgery, The First Affiliated Hospital of Xinjiang Medical University, Urumqi, China.∗ Correspondence: Jiwen Liu, Division of Occupational and Environmental Health, College of Public Health, Xinjiang Medical University, No. 393 Xinyi Road, Urumqi 830011, Xinjiang, China (e-mail: jtsj83@163.com).8 2018 03 8 2018 97 31 e1154327 12 2017 25 6 2018 Copyright © 2018 the Author(s). Published by Wolters Kluwer Health, Inc.2018This is an open access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License 4.0 (CCBY-NC-ND), where it is permissible to download and share the work provided it is properly cited. The work cannot be changed in any way or used commercially without permission from the journal. http://creativecommons.org/licenses/by-nc-nd/4.0Abstract Owing to the transformation of the biomedical model of health, more and more professionals pay close attention to the occupational social psychological factors, such as occupational stress. Due to the socioeconomic impact of occupational stress and the petroleum workers stationed in the unique environment in Xinjiang, a cross-sectional study was carried out between May and December 2016 to investigate the relationship between occupational stress and demographic characteristics. A total of 1480 workers were selected. Occupational stress was evaluated with the Occupational Stress Inventory-Revised Edition. The findings of the present study revealed that the values of the Occupational Roles Questionnaire results (t = 9.266, P < .001) and Personal Strain Questionnaire results (t = 21.381, P < .001) were found to be higher than the national normal. Personal Resources Questionnaire values (t = −17.575, P < .001) were found to be lower than the national normal in petroleum workers stationed in the arid desert, and suggested a strong correlation between occupational stress and demographic characteristics. These data provide evidence that different demographic characteristics are associated with different occupational stress levels in petroleum workers stationed in the arid desert. Keywords arid desertdemographic characteristicsoccupational stresspetroleum workersOPEN-ACCESSTRUE ==== Body 1 Introduction Stress is defined as an environmental stimulus that affects individuals and can provoke physical and psychological reactions.[1] Stress in the workplace is called occupational stress. It occurs because of objective demand and subjective reaction imbalance in certain professional conditions.[2–4] Due to the transition of focus from traditional biomedical model to biopsychosocial model, occupational stress has become a new harmful occupational factor that influences the health of the body and mind similar to the traditional physical, chemical, and biological occupational harmful factors, and can directly or indirectly threaten the workers’ health and ability to work.[5] It has recently become a persistent global problem and thus of increased interest for researchers.[6–9] Adequate tension in the workplace can stimulate the workers’ enthusiasm. However, chronic stress may inflict damage on all aspects of workers’ physiology and psychology.[10,11] Compared to occupational stress, ordinary occupational hazard factors (physical, chemical, and biological), will not lead to specific occupational diseases, but will inflict damage in the form of nonspecific worker's health issues. In mild cases, occupational stress can result in suboptimal health and cause job burnout[12,13] among other symptoms. Severe cases may lead to depression,[14] death,[15] and other serious diseases.[16–18] In addition, occupational stress can cause absenteeism, high employee turnover, and low productivity.[19–22] These consequences will further lead to low quality of life, job dissatisfaction, impaired judgment,[23] decreased work ability, difficulties in social relationships,[24,25] and even accidents.[26] Petroleum workers’ demographic characteristics include gender, age group, educational level, marital status, monthly family income, length of employment, type of work, professional title, shift, and smoking and drinking status. Although the study of different demographic characteristics in relation to occupational stress has made some progress, it is hampered by similarity of the research studies, small sample numbers, choice of research methods, limitations related to decoupling of other potential influential factors, and inconsistent conclusions put forth by the researchers.[27–32] Petroleum workers working in the Xinjiang Field Petroleum Administration belong to a unique category of professionals. Because their task is very difficult, they work long hours and shift work every 6 months. They work in desert areas far from cities, where the weather is harsh, with windy, dry, hot summers and very cold winters. Some studies have reported that the monotonous lifestyle of arid deserts and other harsh environments can have an impact on people's mental and physical health.[33–37] It is thus necessary to carry out the occupational stress investigation for the desert petroleum workers in order to identify necessary prevention work in different demographic populations, and eventually improve the quality of working conditions in the petroleum industry. In this study, we conducted a cross-sectional study of petroleum workers in Xinjiang to investigate the relationship between occupational stress and demographic characteristics. 2 Methods 2.1 Participants This cross-sectional study was performed between May and December 2016. Study subjects were employed for at least one year of both sexes who worked at the Xinjiang Petroleum Administration Bureau of China National Petroleum Corporation in Karamay City, Xinjiang Province, China. A total of 1480 subjects were recruited using a 3-stage stratified sampling method. Finally, based on the Chinese Standard Industrial Classification of the nature of the companies, 740 participants from large companies and 350 from small companies were selected in operating areas, 240 participants from large companies and 150 from small companies were selected in production factories, 130 participants from large companies and 60 from small companies were selected in exploration and development companies. The type of work the participants engaged in included oil transportation, oil extraction, stoker hot note work, geophysical prospecting, and testing, among others. Written informed consent was obtained from all participants. The general characteristics noted for each participant were gender, age (≤30/>30 years), ethnicity (Han/Minority), educational level (Associate's degree or below/Bachelor's degree or higher), marital status (unmarried/married), monthly family income (≤3000/>3000), and so on. 2.2 Occupational Stress Inventory-Revised Edition (OSI-R) The Occupational Stress Inventory Revised Edition (OSI-R) [38] was translated into Chinese to measure occupational stress. This method has been approved for its reliability and validity, and is widely used in different occupational populations throughout China [39,40]. The OSI-R consists of Occupational Role Questionnaire (ORQ), Personal Strain Questionnaire (PSQ), and Personal Resources Questionnaire (PRQ), they were used to evaluate occupational stress level, personal strain level and coping resources respectively. Subjects responded to each item on a 5-point Likert scale ranging from 1 (never) to 5 (always). Raw scores for ORQ were converted to T scores (mean ± SD, 50 ± 10), based on the general population of China. T scores ≥70, between 60 and 69, and ≤59, indicated high, moderate, and low levels of job strain, respectively.[41] 2.3 Questionnaire quality control Prior to administration of the questionnaires, the purpose of the survey, its content, and significance were thoroughly explained to the researchers conducting the experiment. They were also instructed on how they should administer the questionnaires to obtain executive leadership and related health personnel's cooperation and ensure that the participants cooperated well and completed each questionnaire item truthfully and accurately. All questionnaires were handed out and retrieved in the activity center. The questionnaires were completed anonymously within 15 minutes. 2.4 Statistical analysis The survey results were independently entered into the database by 2 researchers and a consistency test was conducted. SPSS for Windows v.17.0 software (SPSS Inc., Chicago, IL) was used for data processing and statistical analysis. The student's t-test test was used to analyze the distribution of general characteristics among different subscales of occupation stress. The χ2 test was used to analyze the distribution of general characteristics among different occupation stress level. The tests were 2 tailed and the significance level was set at P < .05. 3 Results 3.1 Occupational stress variables in the petroleum workers The total scores obtained from the petroleum workers’ ORQ (t = 9.266, P < .001) and PSQ (t = 21.381, P < .001) were found to be higher than the national normal. PRQ values (t = −17.575, P < .001) were found to be lower than the national normal (Table 1). Table 1 Assessment results for the total score and each component of occupational stress . The comparison of each of the components of occupational stress, including the degree of role insufficiency (t = 5.396, P < .001), role ambiguity (t = 18.267, P < .001), role boundary (t = 12.344, P < .001), physical environment (t = 27.601, P < .001), vocational strain reaction (t = 30.731, P < .001), psychological strain reaction (t = 11.855, P < .001), physical strain reaction (t = 19.234, P < .001), and rational coping (t = 27.62, P < .001), showed values that were significantly higher in the petroleum workers than the national normal (Table 1). The degree of role overload (t = –15.974, P < .034), recreation (t = –5.783, P < .001), self-care (t = –4.987, P < .001), and social support (t = –19.384, P < .001), were all significantly lower in the petroleum workers than the national normal (Table 1). 3.2 Association between subscales of occupational stress and demographic characteristics Comparison of 3 subscales of occupational stress scores in different demographic characteristics that included occupational roles (t = 8.835, P = .003), personal strain (t = 11.135, P = .001), and personal resources (t = 4.829, P = .028), showed that the values were significantly higher in individuals with a bachelor's degree or higher level of education, than in those with an Associate's degree or lower level of education. A statistically significant difference was found between groups of different genders 160 (t = 41.517, P < .001, t = 20.004, P < .001), working age (t = 8.132, P = .004, t = 6.874, 161 P = .009), and alcohol consumption (t = 15.981, P < .001, t = 8.422, P = .004) with regard to occupational roles and personal strain. Male scores were higher than female, individuals with shorter working years scored higher than those with longer working history, and those who drank were more likely to score higher than those who did not. The degree of personal strain (t = 5.661, P = .017) was significantly lower in >30 age group than in the ≤30 age group. With regard to personal resources, a statistically significant difference was found in subjects performing different types of work (t = 4.366, P = .005) and working different shifts (t = 4.459, P = .035). The degree of occupational roles (t = 5.661, P = .017) was significantly higher in the primary and secondary groups, than in the vice-senior and senior groups (t = 5.627, P = .018). The degree of occupational roles (t = 5.661, P = .017) was significantly higher in the smoking group, than the nonsmoking group (t = 22.808, P < .001). There were no statistically significant differences among other variables, which included ethnicity, working years, and marital status (P > .05) (Table 2). Table 2 Association between subscales of occupation stress and demographic characteristics . 3.3 Occupation stress level is associated with demographic characteristics The results of this study show a statistically significant difference in occupational stress levels in terms of gender (χ2 = 12.358, P = .002), education level (χ2 = 14.075, P = .001), working years (χ2 = 6.352, P = .042), type of work (χ2 = 10.000, P = .040), professional title (χ2 = 13.881, P = .001), smoking (χ2 = 7.779, P = .020), and drinking (χ2 = 15.563, P < .001) (Table 3). Table 3 Association between occupational stress level and demographic characteristics. 4 Discussion This study investigated the relationship between occupational stress and demographic characteristics in petroleum workers in the Xinjiang arid desert. With the transformation of traditional biomedical model of health to biopsychosocial model, more and more professionals pay closer attention to the occupational social psychological factors. Occupational stress damages physical and mental health, sometimes in nonspecific manner, and may threaten occupational health and working ability. The current research study found that male occupational role and personal strain scores were higher than female, which is consistent with the results of Ning et al.[42] Males tend to take responsibility for the whole family, while also maintaining their own careers, making their jobs more challenging. In comparison, female workers are more likely to get help and social support from others. Lack of support resources for males is more likely to cause psychological stress. Significant differences were found between the >30 age and ≤30 age groups with regard to personal strain. The lower the age group, the higher is the individual nervous response. This was perhaps due to the novelty of the job and lifestyle for the younger workers, who are still trying to figure out the work-life balance without success. Our results also revealed a statistically significant difference between individuals with an Associate's degree or lower education levels and those with a Bachelor's degree or higher education levels, with regard to occupational roles, personal strain, and personal resources. This is because people with high levels of education have higher self-requirements and higher expectations of society. When their work does not meet the individual expectations, it will lead to a decrease in satisfaction with one's work and increase the pressure associated with their job. Significant differences were found between the groups of subjects who have worked >15 and ≤15 years with regard to occupational roles and personal strain. This finding is consistent with the results of Guan et al.[43] This suggests that workers with long employment history can better adapt to the working environment, as they have good mentality, strong comprehensive ability, strong job satisfaction, allowing them to be able to deal with all kinds of stressful situations. The workers who have worked for a shorter amount of time, lack work experience, and therefore must improve their ability to perform necessary work tasks. Due to their aspirations for achievement, the necessity to perform tedious tasks, and fierce competition, they are more likely to feel the occupational stress. This finding is not consistent with the results of Lian et al,[44] which may be attributed to the differences in study subjects and work type. A statistically significant difference was also observed in the different type of work with regard to personal resources. Oil production workers have better coping abilities than oil extraction and Stoker hot note workers. This is most likely due to the different kinds of work involved, the modes of labor employed, as well as the differences in organizational levels and worker roles. The participants’ shift proved to be a statistically significant variable in the personal resources category. This may be because of a decrease in social policy exchange opportunities, which reduces the ability to adapt to various social roles and the time to communicate with family and friends, thus diminishing the ability to cope with tension. Long-term irregular shift operation not only affects the physical health of workers, but can also reduce work efficiency and cause higher absenteeism, increasing workers’ occupational stress problems. The difference in professional title was statistically significant with regard to occupational roles. The people with primary and secondary professional titles had higher occupational roles scores. This is likely because individuals with primary and secondary professional titles have more burdensome jobs, while vice-senior and senior workers were more familiar with the nature of their long work tenure. This finding is consistent with the results of Sliskovic and Maslic.[45] A number of studies[46,47] have found that stress in the workplace is associated with unhealthy behavior in employees, that smokers are more likely to have occupational stress than nonsmokers, and that occupational stress is associated with an increase in alcohol consumption. The results of this study are consistent with domestic and international studies,[48] which believe that smoking or alcohol-drinking workers score higher on occupational stress. Petroleum workers often work overtime and night shifts in order to complete their performance goals and relieve stress by smoking and drinking alcohol, which is bound to have an impact on health in the long run. The petroleum workers’ scores in occupational roles and personal strain categories were found to be higher than the national normal, while personal resources scores were lower. This finding may be related to poor working environment, such as bad weather, dust, noise, presence of crude oil, and they often work overtime and night shifts, and spend an excessive amount of time and energy completing their performance goals, they also lack the time to find relief from the competitive pressures they face, and the absence of proper monitoring maybe another reason which can easily cause fatigue and burnout, thus increasing occupational stress levels. These factors may also increase the risk of workplace accidents. The differences in degrees of occupational stress in different groups in terms of gender, level of education, working years, type of work, job title, smoking and drinking, were statistically significant, indicating that desert petroleum workers have different job intensity. In particular, they are not only affected by poor human ergonomics, physical and chemical factors, but also by harsh natural conditions, and the monotony of everyday life. It thus appears that the distribution of labor mode, work demand, and coping resources is unbalanced among workers, resulting in different degrees of tension. There were some limitations to the present study. The study only focused on the relationship between demographic characteristics and occupational stress whereas other variables are not considered. Second, the cross-sectional design prevented us to explore other causes of occupational stress. In future, we plan to analyze the relationship between other variables and occupational stress and undertake a cohort study to investigate the casual relationship. This will provide more evidence for the importance of understanding stress in these petroleum workers. 5 Conclusions In conclusion, the results of this study revealed that different demographic characteristics are associated with different occupational stress levels in petroleum workers stationed in the arid desert. Male occupational role and personal strain scores were higher than female. The lower the age group, the higher is the individual nervous response. Associate's degree or lower education levels and those with a Bachelor's degree or higher education levels were different with regard to occupational roles, personal strain, and personal resources. Occupational roles and personal strain are also difference in different working years, different type of work with regard to personal resources are difference. The difference in professional title was statistically significant with regard to occupational roles. This suggested a strong correlation between occupational stress and demographic characteristics. Recommendations were made to strengthen health knowledge propaganda and educational training, increase the humanistic care and psychological counseling, popularize knowledge of mental health issues of the workers, alleviate their mental tension and pressure, and build mental health security. Author contributions Conceptualization: Ning Tao, Jiwen Liu. Data curation: Li Ning. Investigation: Ting Jiang, Lingyun Shi. Writing – review & editing: Ting Jiang. Abbreviations: ORQ = Occupational Role Questionnaire, OSI-R = Occupational Stress Inventory-Revised Edition, PRQ = Personal Resources Questionnaire, PSQ = Personal Strain Questionnaire. TJ, NT, and LS contributed equally to this work. This work was supported by the National Nature Science Foundation of China (Grant No.: 81460489) and the Graduate Student Innovation Project of Xinjiang (Grant No. XJGRI2017087). The authors have no conflicts of interest to disclose. ==== Refs References [1] Lazarus RS Stress and Emotion: A New Synthesis . New York, USA : Springer ; 2006 . [2] Sauter S Murphy L Colligan M Stress at Work (NIOSH) . Cincinnati : DHHS (NIOS-)-CDC ; 2009 . [3] Salavecz G Chandola T Pikhart H Work stress and health in Western European and post-communist countries: an East-West comparison study . J Epidemiol Community Health 2010 ;64 :57–62 .19692735 [4] Nixon AE Mazzola JJ Bauer J Can work make you sick? A meta-analysis of the relationships between job stressors and physical symptoms . Work Stress 2011 ;25 :1–22 . [5] Zhou X Xiao Y Research progress on the relationship between occupational stress and occupational health . J Nanchang Univ (Med Edn) 2013 ;53 :79–81 . 86 . [6] Choy H Wong M Occupational stress and burnout among Hong Kong dentists . Hong Kong Med J 2017 ;23 :480–8 .28839120 [7] Zare R Choobineh A Keshavarzi S Association of amplitude and stability of circadian rhythm, sleep quality, and occupational stress with sickness absence among a gas company employees-a cross sectional study from Iran . Saf Health Work 2017 ;8 :276–81 .28951804 [8] Tripathi A Bagchi S Singh J Lifestyle and occupational stress: a potential risk factor for obstructive sleep apnea in nonobese male subjects . J Prosthodont 2017 ;21 :1–6 . [9] Desouky D Allam H Occupational stress, anxiety and depression among Egyptian teachers . J Epidemiol Glob Health 2017 ;7 :191–8 .28756829 [10] Gartner FR Nieuwenhuijsen K van Dijk FJ The impact of common mental disorders on the work functioning of nurses and allied health professionals: a systematic review . Int J Nurs Stud 2010 ;47 :1047–61 .20444449 [11] Zhang Y Liang D Shi X Investigation of occupational stress and quality of life of medical and nursing staff in Shenyang . Environ Occup Med 2012 ;29 :572–5 . [12] Luo H Yang H Xu X Relationship between occupational stress and job burnout among rural-to-urban migrant workers in Dongguan, China: a cross-sectional study . BMJ Open 2016 ;6 :e012597. [13] Johnstone B Kaiser A Injeyan M The relationship between burnout and occupational stress in genetic counselors . J Genet Couns 2016 ;25 :731–41 .27228983 [14] Wang Y Liu G Zhou X Mediating effect of mental elasticity on occupational stress and depression in female nurses . Zhonghua Lao Dong Wei Sheng Zhi Ye Bing Za Zhi 2017 ;35 :436–9 .28780820 [15] Inoue N Otsui K Yoshioka T A simultaneous evaluation of occupational stress and depression in patients with lifestyle-related diseases . Intern Med 2016 ;55 :1071–5 .27150857 [16] Biglari H Ebrahimi M Salehi M Relationship between occupational stress and cardiovascular diseases risk factors in drivers . Int J Occup Med Environ Health 2016 ;29 :895–901 .27869240 [17] Lazaridis K Jovanović J Jovanović J The impact of occupational stress factors on temporary work disability related to arterial hypertension and its complications . Int J Occup Saf Ergon 2017 ;23 :259–66 .27142122 [18] Jiang Y Cui C Ge H Effect of 5-HT2A receptor polymorphisms and occupational stress on self-reported sleep quality: a cross-sectional study in Xinjiang, China . Sleep Med 2016 ;20 :30–6 .27318223 [19] Andersson N Ones DS Sinangil HK Viswesvaran C Integrated Framework Sage , Handbook of Industrial, Work and Organizational Psychology (Vol 2: Personnal Psychology) . London :2001 . [20] Elfering A Grebner S Gerber H Workplace observation of work stressors, catecholamines and musculoskeletal pain among male employees . Scand J Work Environ Health 2008 ;34 :337–44 .18853065 [21] Australian Academic Press , Winefield HA Boyd C Saebel J Job Stress in University staff: an Australian Research Study . 2008 . [22] Elstad JI Vabo M Job stress, sickness absence and sickness presenteeism in Nordic elderly care . Scand J Public Health 2008 ;36 :467–74 .18635730 [23] Nguyen HT Quandt SA Grzywacz JG Stress and cognitive function in Latino farmworkers . Am J Ind Med 2012 ;55 :707–13 .22431234 [24] Lu H Barriball KL Zhang X Job satisfaction among hospital nurses revisited: a systematic review . Int J Nurs Stud 2012 ;49 :1017–38 .22189097 [25] Valiee S Peyrovi H Nasrabadi AN Critical care nurses’ perception of nursing error and its causes: a qualitative study . Contemp Nurse 2014 ;46 :206–13 .24787254 [26] Park YM Kim SY Impacts of job stress and cognitive failure on patient safety incidents among hospital nurses . Saf Health Work 2013 ;4 :210–5 .24422177 [27] Ma CC Andrew ME Fekedulegn D Shift work and occupational stress in police officers . Saf Health Work 2015 ;6 :25–9 .25830066 [28] Xiong J Li W Survey of occupational stress in shift workers in the main city of Chongqing . Med Chongqing 2014 1608–10 . [29] Caciari T Tomei G De Sio S Evaluation of some cardiovascular risk parameters in health professionals exposed to night work . Ann Ig 2013 ;25 :23–30 .23435777 [30] Sultan-Taïeb H Chastang JF Mansouri M The annual costs of cardiovascular diseases and mental disorders attributable to job strain in France . BMC Public Health 2013 ;13 :748.23941511 [31] Kelly BD O’Callaghan E Waddington JL Schizophrenia and the city: a review of literature and prospective study of psychosis and urban city in Ireland . Schizophr Res 2011 ;116 :75–89 . [32] Dupere V Perkins DD Community types and mental health: a multilevel study of local environment stress and coping . Am J Community Psychol 2007 ;39 :107–18 .17437190 [33] Ljoså CH Tyssen R Lau B Perceived mastery of work among shift workers in the Norwegian offshore petroleum industry . Ind Health 2013 ;51 :145–53 .23095327 [34] Liu XD Li JG Lian YL Research on mental fatigue of soldiers in the arid desert . Hosp Adm J Chin People's Lib Army 2011 ;19 :124–6 . [35] Tao N Zhang J Song Z Relationship between job burnout and neuroendocrine indicators in soldiers in the Xinjiang Arid desert: a cross-sectional study . Int J Environ Res Public Health 2015 ;12 :15154–61 .26633442 [36] Jiang T Ge H Sun J Relationship between occupational stress, 5-HT2A receptor polymorphisms and mental health in petroleum workers in the Xinjiang Arid desert: a cross-sectional study . Int J Environ Res Public Health 2017 ;14 :1–1 . [37] Jiang Y Tang J Li R Effect of 5-HT2A receptor polymorphisms, work stressors, and social support on job strain among petroleum workers in Xinjiang, China . Int J Environ Res Public Health 2016 ;13 :1–0 . [38] Osipow SH Occupational Stress Inventory; Revised Edition (OSI-R) . Odessa, FL, USA : Psychological Assessment Resources ; 1998 . [39] Wu H Zhao Y Wang J Factors associated with occupational stress among Chinese doctors: a cross-sectional survey . Int Arch Occup Environ Health 2010 ;83 :155–64 .19701645 [40] Yang X Wang L Ge C Factors associated with occupational strain among Chinese teachers: a cross-sectional study . Public Health 2011 ;125 :106–13 .21288545 [41] Yang XW Wang ZM Jin TY Study on the occupational stress norm and its application for the marketing group, public service/safety group and production laborer group . Wei Sheng Yan Jiu 2006 ;35 :594–608 .17086713 [42] Ning L Li F Yang X Study on the occupational stress and job burnout in petroleum workers in the Xinjiang Arid desert . Wei Sheng Yan Jiu 2014 245–9 .24868977 [43] Guan S Zhao J Wang L The relationship between mental health and job burnout among different working years professional people . J North Sichuan Med Coll 2014 ;29 :16–9 . [44] Lian Y Liu J Zhang C A comparative study on the level of stressful responses of mental workers with different individual characteristics . J Xinjiang Med Univ 2008 ;31 :8–12 . [45] Sliskovic A Maslic SD Work stress among university teachers . Arh Hig Rada Toksikol 2011 ;62 :299–307 .22202463 [46] Heikkilä K Nyberg ST Fransson EI Job strain and tobacco smoking: an individual-participant data meta-analysis of 166,130 adults in 15 European studies . PLoS One 2012 ;7 :e35463.22792154 [47] Heikkilä K Fransson EI Nyberg ST Job strain and health-related lifestyle: findings from an individual-participant meta-analysis of 118,000 working adults . Am J Public Health 2013 ;103 :2090–7 .23678931 [48] Vidal J Abreu A Portela L Psychosocial stress at work and alcohol consumption patterns in offshore oil workers . Cad Saude Publica 2017 ;33 :417.