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Does Emotional Labor Increase the Risk of Suicidal Ideation among Firefighters?

Purpose To investigate whether emotional labor is associated with suicidal ideation in Korean firefighters. Materials and Methods Data were obtained from the Firefighter Research: Enhancement of Safety & Health (FRESH) Study, which was designed to investigate the effects of job characteristics on mental and physical health among Korean firefighters. A total of 18101 firefighters were chosen from a nationwide sample. The Korean Emotional Labor Scale (K-ELS) was used to evaluate exposure to emotional labor, which consisted of five sub-factors: emotional demand and regulation, overload and conflict in customer service, emotional disharmony and hurt, organizational surveillance and monitoring, and lack of a supportive and protective system in the organization. Results Firefighters who were in the risk group were more likely to experience suicidal ideation than those in the normal group for each of the five sub-scales of emotional labor. The estimated mean values for suicidal ideation in the risk group were significantly higher than those in the normal group: 1.667 (95% CI: 1.344–2.069) for emotional demand and regulation, 1.590 (95% CI: 1.243–2.033) for overload and conflict in customer service, 2.409 (95% CI: 1.954–2.969) for emotional disharmony and hurt, 2.214 (95% CI: 1.832–2.676) for organizational surveillance and monitoring, and 1.665 (95% CI: 1.387–1.999) for lack of a supportive and protective system in the organization. Conclusion These results suggest that experience and exposure to chronic and excessive emotional labor might play a crucial role in the development of suicidal ideation among firefighters.


INTRODUCTION
When interacting with customers, service workers may be required to manage the expression of their own feelings in carrying out their job. These emotional interactions with customers may occur directly or indirectly. Emotional labor occurs when emotion work is required in exchange for something, such as wages or some other type of valued compensation. Wharton 1 proposed that these actions are not only performed for a wage, but they may also be under the control of others.
Emotional laborers are more likely to hide their real emotions because their emotional expressions while performing workrelated duties should be displayed according to organizational goals and guidelines. However, these chronic interactions involving restricted emotional expression with customers may lead to both physical and mental depletion. Indeed, emotional labor has been shown to be associated with physical and mental health problems 2 due to surface acting (the act of suppressing or hiding one's own feelings that occur during work to express positive emotions) and deep acting (where individuals try to consciously change their feelings to truly express positive emotions, rather than give a superficial appearance of changed feelings). 3 Mental health problems resulting from emotional labor among service workers have been widely reported. In Korea, recent studies have documented that emotional laborers, such as nurses, dental hygienists, call center workers, sales workers, bankers, and hoteliers, are at high risk for depressive symptoms and burnout. 4,5 Emotional expression appearing as surface acting in reflection of organizational goals, rather than individual spontaneity, can affect depressive symptoms and burnouts, 6,7 and depressive symptoms and burnout have been found to be strongly associated with suicide attempts. 8,9 Further, about 60% of suicide deaths have been shown to be associated with major depressive disorder or a mood disorder. 10 Suicide-related deaths are steadily increasing. Currently, more than 800000 people worldwide die each year from suicide. 11 Suicide is reported to be the second cause of death among workers aged 15 to 29 years. 12 From 2012 to 2016, the occupations with the highest number of suicides were service and sales associates. 13 This is especially concerning as the service industry continues to expand and strengthen, making the risk of suicide for service workers an important issue.
As the duties of firefighters have expanded from fire prevention and suppression to related tasks, such as rescue and emergency service, the proportion of interpersonal tasks has been increasing. In addition, firefighters may face civilians who are exposed to feelings of loss, exposure of death, mental trauma, and anger in fire, rescue, and emergency situations. Even if firefighters are trained in the appropriate procedures for each situation, they may not be emotionally prepared for nervous or stressful situations or interactions involving customer service. In this way, firefighters experiencing confrontations with civilians are exposed to emotional labor. According to the occupational status survey of emotional labor, the emotional labor score of fire officials was 3.74 out of 5 points, and they were classified as a high risk occupational group for emotional labor. 14 Firefighters were more likely to experience emotional labor than other occupational groups (e.g., manufacturing workers).
Although there has been a significant change in the psychological health of firefighters, there are few studies on the relationship between emotional labor and suicide in firefighters. Therefore, the present study aimed to examine the relationship between emotional labor and suicidal ideation for firefighters.

Study participants
The participants in this study included individuals who completed the online survey "Job Contents And Health Survey of Firefighters" conducted for the FRESH (Firefighter Research: Enhancement of Safety & Health) Study entitled "The Study on Physical and Mental Health Promotion of Firefighters through Lifetime Health Risk Management System in Korean Firefighters. " Of 19203 total respondents who participated, 18101 firefighters were included for the final analysis of this study. We excluded 1102 individuals who did not have complete responses (Fig. 1). This study was approved by the Institutional Review Board of Yonsei University Wonju College of Medicine (Approval No. CR316014).

Measures
The data for this study were collected using an online-based, self-report questionnaire. All participants were asked about general characteristics, occupational characteristics, characteristics of past work, job stress, emotional labor, working violence, health behavior, and health status.

Emotional labor
Emotional labor was measured using the Korean Emotional Labor Scale (K-ELS), which was designed to evaluate the work environment and factors related with emotional labor. The emotional labor questionnaires consist of 24 questions in five areas including, 1) emotional demands and regulation (5 items), 2) overload and conflict of customer service (3 items), 3) emotional disharmony and hurt (6 items), 4) organizational surveillance and monitoring (3 items), and 5) lack of a supportive and protective system in the organization (7 items). Each item on emotional labor was rated on a 4-point Likert scale (1=disagree completely, 2=disagree, 3=agree, 4=agree completely). The five subfactors were converted into a score from 0-100. Higher scores represented a higher intensity of emotional labor. Results of reliability analysis for the five sub-factors in the original study showed Cronbach's α values ranging from 0.761 to 0.904. 15 Cronbach's α for the five sub-factors in this study ranged from 0.772 to 0.928. In this study, the five sub-factors were further divided into a normal and risk group by using cut points determined according to gender.

Suicidal ideation
Suicidal ideation was measured by asking, "(In the past 12 months) Have you thought about committing suicide?" There was a dichotomous response category (yes vs. no).

Statistical analysis
To compare suicidal ideation according to general characteristics, occupational characteristics, health behavior, health status, trauma exposure, and emotional labor, we conducted independent two-sample t-tests and chi-square tests. A multivariate Poisson regression model was used to evaluate the independent association of emotional labor with suicidal ideation. All analyses adjusted for several covariates, such as age, gender, education, marital status, main duty, shift work, smoking, drinking alcohol, participant health status, and trauma exposure. A few firefighters reported that they have thoughts of "committing suicide. " When facing such rare events in data analysis, Poisson analysis is very useful. 16 The results are expressed as relative risks (RRs) with 95% confidence intervals (CI). p<0.05 was considered statistically significant, and all statistical analysis were performed using SPSS (version 23.0; IBM Corp., Armonk, NY, USA).

Intensity of emotional labor in firefighters
The distributions of participants in the risk group for each of the five sub-factors of emotional work were 11.7% for emotional demands and regulation, 8.5% for overload and conflict of customer service, 9.7% for emotional disharmony and hurt, 17.9% for organizational surveillance and monitoring, and 36.2% for lack of a supportive and protective system in the organization.

Differences in suicidal ideation according to general characteristics of the study participants
Of the 18101 firefighters, 489 (2.7%) reported that they have thoughts of committing suicide. Suicidal ideation was more common among firefighters who were divorced, bereaved, and separated (5.1%), compared to those who were unmarried (2.1%) and married (2.9%) (p<0.001). The proportion of participants with suicidal ideation by main duty was higher for administrative or education (3.3%) than for firefighting (2.9%), rescue (2.4%), and emergency medical aid (2.2%) (p=0.030). Participants who were smoking (3.3%) and drinking more than three times a week (5.1%) showed a higher proportion of suicidal ideation than their counterparts (p<0.001). For the five sub-factors of emotional labor, all of the risk groups had significantly more suicidal ideation than the normal groups: emotional demands and regulation, 5.4% (p<0.001); overload and conflict in customer service, 5.3% (p<0.001); emotional disharmony and hurt, 7.7% (p<0.001); organizational surveillance and monitoring, 5.8% (p<0.001); and lack of a supportive and protective system in the organization, 4.2% (p<0.001) ( Table 1).

DISCUSSION
The present study aimed to examine the relationships between emotional labor and suicidal ideation for firefighters. Our findings indicated that participants in the risk groups for each of the five sub-factors of emotional work comprised 11.7% for emotional demands and regulation, 8.5% for overload and conflict of customer service, 9.7% for emotional disharmony and hurt, 17.9% for organizational surveillance and monitoring, and 36.2% for lack of a supportive and protective system in the organization. Previous studies have documented that a lower degree of organizational commitment 17 and higher frequency of emotional expression and emotional dissonance are associated with lower job satisfaction. 18 Among firefighters at the Seoul Emergency Operations Center, social support had a mediating effect on the relationship between emotional labor and job performance. 19 The emotional labor of firefighters has also been found to have a major risk factor affecting mental health 20 and to have a negative effect on turnover intentions. 21 In addition, emotional labor was a major predictor of reduced work efficiency and increased work disability for firefighters. Because firefighters must meet various demands from civilians, job stress and posttraumatic stress can result in severe adverse consequences, such as de- pression, burnout, and suicide. [22][23][24] In 2015, 12 Korean firefighters died due to apparent suicide, which is six times higher than the number of firefighters who died due to accidents while working. The number of firefighters who committed suicide during the past 5 years was 41, which was higher than the number of firefighters who died while performing their duties.
Multivariate Poisson analysis showed that the five sub-scales of emotional labor affected suicidal ideation in this study. The RRs for suicidal ideation were more than approximately two times higher in the risk group than in the normal group for the sub-scales of overload and conflict in customer service and organizational surveillance and monitoring. Emotional disharmony and hurt are the items that measured the emotional disharmony caused by the clash between the actual emotions of the worker and the emotional expression norms required by the workplace, and the degree of damage to the various types of minds during customer interactions. Emotional dissonance is well known to have a negative impact on emotional workers. 25 The organizational culture of firefighters reflects an army-like class structure, and they have a strict sub-culture, compared to other occupational groups. The higher proportions of risk groups associated with the emotional demands on firefighters may be due to the hierarchical organizational climate of the firefighters. Among the sub-factors of emotional labor, organizational surveillance and monitoring, a sub-factor related to the organization, was a measure of the degree to which workers felt that it was hard to monitor how well they responded to customers and applied it unilaterally to performance appraisal and evaluation. 15 An expansion in the monitoring system has resulted in workers with increasing emotional stress in the workplace 26 and increased fatigue during their working hours. 27 In addition, lack of a supportive and protective system in the organization is a measure of the workplace support system that can be used to alleviate problems and can facilitate progress for organizational management plans or actions when a problem occurs for the customer. 15 Studies have shown a positive effect on emotional labor when the supportive culture of an organization is high. 28 In particular, officials of government organizations tend to underestimate emotional labor. 29 In Korea, it has been reported that emotional expression of officials is suppressed and that evaluation thereof is unnecessary. 30 Possible mechanisms for the link between emotional labor and suicidal ideation have been documented. Suppressing emotions while performing emotional service can result in the loss of personal resources. 31 According to the Conservation of Resources theory, 32 the loss or threat of personal resources increases physiological arousal and health problems. Suppressing emotions requires more energy resources, as exhibited by increased physiological arousal and higher levels of glucose. 33 As a result, persistent exposure to stress due to excessive and chronic emotional demands might activate the stress system, including the hypothalamic pituitary adrenal axis and the sympathetic nervous system. Furthermore, if the demand for emotion regulation is excessive and persistent, it can lead to depression. 34 Another mechanisms can be discussed in that surface acting results in emotional burnout due to efforts to fake or suppress negative emotions, 35 which can contribute to health deterioration. 36 Surface acting can lead to energy deficits from persistent internal tension due to emotional dissonance resulting from a collision between the behavior of suppressing one's feelings and the emotions. The continuing experience of emotional dissonance can play a crucial impact on the loss or threat of resources and eventually to exhaustion. 37 Depression and burnout caused by emotional labor are closely related to suicide and suicide attempts and are known to be important risk factors. 38 Of the total study participants, 489 (2.7%) answered that they considered attempting suicide in the past year.
This study has several strengths. First, the relationship between individual sub-factors and suicidal ideation was examined using the Korean Emotional Labor Scale standardized with consideration for the socio-cultural context and the qualitative aspect of emotion in Korea. Second, the relationship between emotional labor and suicidal ideation in firefighters, which is a recent issue, was confirmed through a Poisson regression analysis. Third, this study was analyzed using a nationwide survey that was completed by 50% of all firefighters in Korea. Fourth, findings from this study can be used as a basis for the necessity of an intervention program with which to examine and reduce suicidal ideation in firefighters to prevent suicidal behavior.
There are some potential limitations to this study. First, survey completion methods may have varied because it was completed online. Second, because the design of this study was crosssectional, no causal relationship between emotional labor and suicidal ideation can be specified. Further, it is necessary to conduct prospective studies to confirm the association between emotional labor and suicide. Additionally, it is not clear whether suicidal ideations were caused by emotional labor during work because questionnaire items of suicidal ideation concerned the past 12 months. However, a recent study showed that long lasting exposure to emotional labor in the short term cannot be ignored, although in general, negative emotions, such as emotional dissonance, can be generated by accumulated emotional labor. 39 In conclusion, our findings suggest that emotional labor is associated with suicidal ideation in Korean firefighters. Emotional labor is not limited to the service industry and extends to all sectors of industry. Therefore, additional research is required to examine emotional workers from several service industries, including face-to-face service businesses. This study confirmed the relationship between emotional labor and suicidal ideation found in previous studies on firefighters who are emotional workers in the public service sector. This result suggests that continuous exposure and experience of emotional labor in the work of a firefighters play a role in increasing suicidal ideation. The results of this study can contribute to suicide prevention for firefighters by informing mental health promotion management programs to reduce the negative influence of emotional labor on firefighters.