A literature review of the health effects of workers responding to the Great East Japan Earthquake

Abstract

Objectives: In the event of a disaster, both victims and first responders are exposed to health risks. The purpose of this study was to investigate the health effects of workers responding to disasters following the Great East Japan Earthquake (GEJE). Methods: We reviewed the literature on the health effects of workers responding to disasters at GEJE. PubMed and Ichu-Shi Web (an online search database for Japanese medical literature) were utilized. After the screening, we excluded papers that did not meet our inclusion criteria. Results: We identified 25 papers matching our criteria. Papers on the health of workers who responded to disasters was primarily focused on medical professionals, public servants, and emergency professionals. Although many papers focused on the mental effects of health effects of health consequences, suggesting that many occupations increase the risk of depression and PTSD, some also reported on positive factors, such as improving work engagement by overcoming difficulties. Emergency professionals were also at risk for PTSD and depression, however, some reported that the risk was relatively low compared to other occupations. Conclusions: In the event of a disaster such as GEJE, many first responders were traumatized. Attention should be paid to the support of survivors during a disaster, but the health effects of workers involved in disaster response should also be addressed. In the future, it is necessary to establish a system to monitor and support the health of first responders.

Introduction

Various types of disaster events occur all over the world, and they include natural disasters, such as earthquakes, tsunamis, and typhoons; industrial disasters, such as fires, explosions, and building collapses; and man-made disasters, such as terrorism and crimes. Some workers who are engaged in response work and recovery work after the disasters not only suffer directly from the disaster, but also witness tragic situations or are exposed to hazardous factors¹⁾. Occupational health professionals, who are in charge of the organization to which the workers belong, are required to minimize these health effects when a disaster event occurs. Therefore, they have to participate in disaster planning and disaster drills within in the organization in order to effectively accomplish their goal of minimizing adverse health effects. As one occupational health professional does not have a lot of disaster response experience, it is considered effective to learn from past experiences and multiple perspectives from previous disaster events. However, the papers on occupational health activities at the time of disaster events are limited compared to the number of events.

The Great East Japan Earthquake (GEJE) of March 2011 is considered a multi-disaster, as damage was caused by the earthquake, large tsunami, and the nuclear power plant accident¹⁾. Many first responders fulfilled their duties in various ways, including evacuation and rescue of residents, searching for missing persons, managing shelters, and decontamination of radioactive materials, amongst others, for recovery.

In order to accumulate knowledge from previous experiences on occupational health activities at a disaster event, we reviewed papers describing the health issues of workers related to the nuclear accident, which were classified into workers engaged in work at the Fukushima nuclear power plant²⁾, workers engaged in local decontamination work³⁾, and other workers.

In this study, we reviewed the papers related to health effects of workers who responded to the GEJE, excluding those related to the nuclear accident. Papers related to workers working at the nuclear power plant were excluded from this study because they have been studied in the past⁴⁾, and the purpose of this review is not to examine the health effects of radiation.

Materials and Methods

PubMed and Ichu-Shi Web (an online search database for Japanese medical literature) were used for our literature search in November 2019. The searched keywords utilized in PubMed were as follows: Great East Japan Earthquake AND disaster worker (MeSH Terms or All Fields); Great East Japan Earthquake AND workplace (MeSH Terms or All Fields); Great East Japan Earthquake AND occupational health (MeSH Terms or All Fields); and Great East Japan Earthquake AND worker (MeSH Terms or All Fields). We utilized the corresponding formula on Ichu-Shi Web.

A total of 144 papers were selected for primary screening: 80 papers form PubMed, 60 papers from Ichu-Shi Web, and 4 referenced within those papers. After screening, we extracted papers that met our inclusion criteria. In this case, the exclusion criteria were: a paper targeting nuclear-related workers, a paper in which health indicators were not quantitative, a non-original paper, and a review paper. The inclusion criteria were, in principle: an original paper, a paper that was not about a nuclear worker, and a paper describing health effects on workers. We finally excluded 119 papers and identified 25 papers that met our objectives (Fig. 1).

Fig. 1.

Paper selection flow in our review

Results

The subjects in the 25 papers were classified into three categories according to occupation. The first category is healthcare professionals (10 papers), including Disaster Medical Assistance Team (DMAT), nurses, various medical staff, general hospital workers, and dental staff. The second category comprised public servants (10 papers), and the third category included emergency professionals (7 papers): relief workers, rescue workers, defense force workers, and firefighters. Studies with multiple objects were counted independently, allowing duplication.

Medical professionals

Papers on medical professionals are summarized in Table 1. Matsuoka et al.⁵⁾ studied dentists and suggested that mental status before dispatch might be related to the Impact of Event Scale-Revised (IES-R) after dispatch. Matsuoka et al.⁶⁾ focused on concerns regarding exposure to radiation. Matsuoka, in this study on DMAT, evaluated radiation concerns using a questionnaire and noted its association with mental stress. Sakuma et al.⁷⁾ indicated that the likelihood of Post Traumatic Stress Disorder (PTSD) and depression was increasing. The authors also noted that lack of rest and lack of communication in the workplace could be factors that increased the risk of PTSD. In addition to healthcare professionals, public servants and firefighters were evaluated in Sakuma dissertation. Yokoyama et al.⁸⁾ published a paper observing public nurses. In this paper, they pointed out that the timing of the disaster dispatch and the number of working hours per day may affect the mental health of nurses after dispatch. Nishi et al.⁹⁾ pointed out that the Peritraumatic Distress Inventory (PDI) score may function as a predictor of PTSD symptoms. The paper also noted that watching news about the earthquake for more than 4 hours a day may be a predictor of PTSD symptoms. Saigo et al.¹⁰⁾ evaluated the posttraumatic stress symptoms (PTSS) of DMAT and showed that high controllability for intrusion might be a factor in reducing PTSS. Tsutsui et al.¹¹⁾ evaluated Prolonged Grief Disorder (PGD) among public hospital workers after GEJE. The paper suggested that PGD might be qualitatively independent of PTSD and major depressive disorder (MDD), even in non-Western disasters. Kawashima et al.¹²⁾ pointed out that PDI score was associated with PTSD symptoms, and suggested evaluating PDI scores in support of DMAT during disasters. Sato et al.¹³⁾ conducted qualitative analysis with interview data to nurses who were working at a hospital in the area in Fukushima Prefecture that was affected by the complex disaster, and reported that they experienced some positive impacts, such as an increase in occupational satisfaction, becoming much more appreciative of their lives and even small things; however, 39% of the participants were categorized as at high risk for PTSD. Nishi et al.¹⁴⁾ observed that resilience at baseline and post-traumatic growth after rescue activities were predictors of high work engagement after 4 years among disaster medical assistance team members who were engaged in rescue activities.

Table 1. Summary of papers on the health effects of medical professionals after the Great East Japan Earthquake

Auther	Subject	Follow-up after GEJE	Measurements	Major findings
Related to depression and PTSD
Matsuoka H, et al.5)	Dental care staff	1 and 2 months after the disaster	IES-R, POMS	Depression and anxiety symptoms before dispatch may be related to IES-R after dispatch.
Matsuoka Y, et al.6)	DMAT	1 month after the disaster	Self-report questionnaire, K6, CES-D, PDI, and IES-R	Radiation concerns have been linked to mental stress indicators.
Sakuma A, et al.7)	public employees, health care professionals, Firefighters	2 months after the disaster	PCL-S, PHQ-9, K6	Healthcare workers are exposed to PTSD and the risk of depression, and these risks can be exacerbated by lack of rest. Poor workplace communication was a risk of PTSD and depression.
Yokoyama Y, et al.8)	public health nurses	1 year and 9 to 10 months after the disaster	Self-report questionnaire	The phase of the disaster dispatch afterwards affected the mental state of nurses, and it was found that the initial dispatch was heavy.
Nishi D, et al.9)	DMAT	1 and 4 months after the disaster	PDI, IES-R	The total PDI scores may be useful as predictors of PTSD symptoms.
Saigo T, et al.10)	DMAT	1.5 months after the disaster	Questionnaire, IES-R-J, PDI, CES-D, CARS	None of the study participants developed PTSD, but high controllability for intrusion may be a risk mitigation factor for PTSS.
Tsutsui T, et al.11)	employees of a public general hospital	7 months after the disaster	ICG, IES-R, CES-D	PGD was found to be qualitatively different from PTSD and MDD.
Kawashima Y, et al.12)	DMAT	4 years after GEJE	IES-R, MBI, PDI	The PDI score served as a measure of PTSD symptoms and burnout.
Focused on positive aspects
Sato H, et al.13)	Nurses of a general private hospital	1 year and 4 to 7 months after the disaster	Preinterview questionnaire, IES-R Formal in-depth interviews and focus group discussions	Some experienced some positive impacts although 39% of the participants were categorized as at high risk for PTSD.
Nishi D, et al.14)	DMAT	1 year and 9 months to 2 years after the disaster	RS-14, Peri-traumatic distress (PDI), SF-PTGI, UWES-9, IES-R	Resilience at baseline and post-traumatic growth after rescue activities were predictors of high work engagement after GEJE.

CARS, Cognitive Appraisal Rating Scale; CES-D, Center for Epidemiologic Studies Depression Scale; DMAT, Disaster Medical Assistance Team; ICG, Inventory of Complicated Grief; IES-R, Impact of Event Scale-Revised; K6, Kessler 6 scale; MBI, Maslach Burnout Inventory; PCL-S, PTSD check list (specific); PDI, Peritraumatic Distress Inventory; PHQ-9, Patient Health Questionnaire-9; POMS, Profile of Mood States; PTSD, post-traumatic stress disorder; RS-14, the short version of the Resilience Scale; SF-PTGI, Posttraumatic Growth Inventory short form; UWES-9, Utrecht Work Engagement Scale 9.

Public servants

Papers on public servants are summarized in Table 2. Suzuki et al.¹⁵⁾ focused on public servant burnout. This study of public servants in Miyagi Prefecture found that one of the risk factors for burnout was severe damage to their house. It was also shown that not taking a rest day once a week was a risk increasing factor for mental health distress in another paper from Suzuki et al.¹⁶⁾ According to Fukuzawa et al.’s paper¹⁷⁾, to reduce mental health distress, it was effective to reduce overtime hours or reduce contact with residents depending on the situation of workers’ damage. Good workplace communication was effective regardless of the situation. Aoki’s paper¹⁸⁾ demonstrated that differences in working hours, affiliations, and appointment periods affected depression at the scene of a disaster. Ueda et al.¹⁹⁾ also suggested that criticism from local people may be a factor in PTSD’s risk and psychological distress, as well as poor workplace communication. Sakuma et al.⁸⁾ noted that public servants were also at risk for PTSD and depression, and lack of workplace communication and lack of breaks were found to be risk factors. Maeda et al.²⁰⁾ indicated that public servants working in the disaster-stricken area were at increased risk of depression, and that strong complaints from local residents increased the risk. Monma et al.²¹⁾ showed that leg extension power was associated with the Japanese-language version of the Impact of Event Scale-Revised (IES-R-J) in men. Tsuno et al.²²⁾ reported on a study on PTSS and resilience of civil servants: the study suggested that resilience and PTSS might be negatively correlated. Konno et al.²³⁾ compared the changes in blood pressure after a disaster with civil servants and the general public, and noted that civil servants tend to have higher systolic and diastolic blood pressure.

Table 2. Summary of papers on the health effects of public servants after the Great East Japan Earthquake

Author	Subject	Follow-up after GEJE	Measurements	Major findings
Related to depression and PTSD
Suzuki Y, et al.13)	public servants of Miyagi prefecture	2 months and 1 year and 4 months after the disaster	MBI-GS, exhausting plus1	Severe damage to the house is a risk factor for burnout.
Suzuki Y, et al.16)	public servants in the Miyagi prefectural government	7 months after the disaster	K6	Not taking holidays once a week is a risk factor for mental distress.
Fukasawa M, et al.17)	public servants in the Miyagi prefectural government	2 months after the disaster	K6	Workers with less disaster-related damage: reducing overtime hours decreases mental health distress Workers with severe disaster-related damage: avoiding contact with residents reduces mental health distress Factors reducing mental health distress in both groups: good workplace communication
Aoki S18)	employees of Iwate prefecture	The same year and 1 year after the disaster	Evaluation of depression: The Brief Job Stress Questionnaire	Differences in the number of overtime hours, departments, and appointment hours affect the depression of local government officials in the affected areas.
Ueda I, et al.19)	workers of local SHAKYOs	1 year and 8 to 11 months after the disaster	PTSD: PCL-S, PHQ-9, K6	Criticism from local people and lack of communication in the workplace contributed to PTSD’s risk and psychological distress.
Sakuma A, et al.8)	public employees, health care professionals, Firefighters	1 year and 2 months after the disaster	PCL-S, PHQ-9, K6	Municipalities are also exposed to PTSD and the risk of depression, and these risks can be exacerbated by lack of rest. Poor workplace communication was a risk of depression.
Maeda M, et al.20)	municipality employee of two towns located within 30km of the NPP	2 years to 2 years and 6 months after the disaster	IESR-J, MINI Interviews performed by pairs of a psychiatrist and a psychologist	Strong complaints from residents are increasing the risk of depression for public servants.
Momma H, et al.21)	employees of the Sendai Oroshisho Center	7 months before to 1 year and 5 months after the disaster	IESR-J, maximal bilateral leg extension power, questionnaire, physical data	Leg extension power may be one of the factors reducing PTSD symptoms in men.
Tsuno K, et al.22)	municipality employee of Kanoto area	6 months after the disaster	CD-RISC, PTSS	Resilience groups tended to have lower PTSS symptoms.
Focused on physical health
Konno S, et al.23)	public employees of the town of Watari	4 to 8 months after the disaster	SBP, DBP	Public employees tended to have higher systolic and diastolic blood pressures than general population.

CD-SISC, Connor-Davidson Resilience Scale; DBP, diastolic blood pressure; IES-R-J, Japanese-language version of the Impact of Event Scale-Revised; K6, Kessler 6 scale; MBI-GS, Maslach Burnout Inventory-General Survey; MINI, The Mini-International Neuropsychiatric; PCL-S, PTSD check list (specific); PHQ-9, Patient Health Questionnaire-9; PTSD, post-traumatic stress disorder; PTSS, Posttraumatic Stress Symptoms; SBP, systolic blood pressure.

Emergency professionals

Papers on emergency professionals are summarized in Table 3. Nagamine et al.²⁴⁾ clarified that living environment was a risk factor for psychological distress in the multiple logistic regression analysis of Defense Force workers. Dobashi et al.²⁵⁾ showed that in Defense Force workers, although exposure to the corpses could be a factor in increasing IES-R and Kessler 10 (K10), the study participants generally tended to have lower psychological distress. Osawa et al.²⁶⁾ also reported that although the activities, including sleep during the dispatch, could affect the IES-R and K10, the firefighters observed were generally in good mental condition. The research by Sakuma et al.⁸⁾ mentioned above demonstrated that firefighters had a lower risk of probable PTSD and probable depression compared to other occupations.

Table 3. Summary of papers on the health effects of emergency professionals after the Great East Japan Earthquake

Author	Subject	Follow-up after GEJE	Measurements	Major findings
Related to depression and PTSD
Nagamine M, et al.24)	Defense Force workers	1, 6, and 12 months after the disaster	IES-R, K10, PTSR, GPD	Living environment is a risk factor for psychological distress.
Dobashi K, et al.25)	Defense Force workers	6 months after the disaster	IES-R, K10	Despite the possibility that cadaver exposure or age was a risk for psychological distress, the multiple logistic regression analyzes did not show a strong association between IES-R and factors.
Osawa T, et al.26)	Firefighters	6 months after the disaster	IES-R, K10	Sleeping and physical conditions may affect IES-R and K10, but the observed firefighters’ risk of psychological distress was not high.
Sakuma A, et al.8)	Public employees, health care professionals, Firefighters	1 year and 2 months after the disaster	PCL-S, PHQ-9, K6	Firefighters have a lower risk of psychological distress, such as PTSD and depression, compared to other job categories.
Setou N, et al.27)	Relief workers from health care, consultation services, home care services, and so on.	2 year and 6 to 9 months after the disaster	Self-report questionnaire, K6, Pro-QOL	In the fatigue group, K6 and some of the subscale scores of Pro-QOL are higher than the non-fatigue group.
Fushimi M28)	Firefighters of Akita city	shortly, 2 weeks and 1 month after the disaster	IES-R, Interview by medical staffs, provision of information on CIS and PTSD.	The mental condition of the firefighters observed was relatively good.
Noda Y, et al.29)	Paramedics and firefighters	4 year and 1 to 5 months after the disaster	IES-R, CD-RISC	High resilience and education may reduce PTSD risk.

CD-SISC, Connor-Davidson Resilience Scale; CIS, Critical Incident Stress; GPD, General Psychological Distress; IES-R, Impact of Event Scale-Revised; K6, Kessler 6 scale; K10, Kessler 10 scale; PCL-S, PTSD check list (specific); PHQ-9, Patient Health Questionnaire-9; Pro-QOL, Professional quality of life measure; PTSD, post-traumatic stress disorder; PTSR, Post Traumatic Stress Reaction.

Setou et al.²⁷⁾ found that among relief workers, the fatigue group tended to have higher Kessler 6 and some subscale scores of the Professional Quality of Life measure. Fushimi et al.²⁸⁾ also noted that the firefighters studied were maintaining a relatively good mental state. Noda et al.’s study²⁹⁾ of firefighters and paramedics suggested that high resilience and well-educated individuals had a low risk of PTSD.

Discussion

The papers extracted in this study were classified into three categories: medical professionals, public servants, and emergency professionals, with few other workers. Most of health effects evaluated in papers were related to mental health effects of disaster response, principally related to PTSD and depression.

Medical professionals

This study found that healthcare workers working at disaster sites, such as GEJE, have an increased risk of PTSD and depression. However, some observed populations did not develop PTSD; it was also suggested that pre-dispatch resilience and assessment may predict PTSD and depressive symptoms. It is noteworthy that Nishi and Sato’s paper also evaluated not only outcomes, such as PTSD and depression, but also positive aspects, such as improving workers’ self-fulfillment. Workers are temporarily overloaded and faced with a difficult working environment, but there appears to be a certain number of improvements in feelings of self-fulfillment and work engagement. Although the temporary burden of healthcare workers during the disaster is unavoidable, care should be taken to ensure that workers are not burdened, while keeping in mind these positive aspects. It was suggested that securing rest periods and ensuring good workplace communication might be effective in reducing the risk of PTSD and depression. It has been noted in a past paper that the support of colleagues in the workplace is a suppressive factor in depression among healthcare workers³⁰⁾, thus maintaining a good work environment is important both in “normal times” and during disasters.

Public servants

Public servants are one of the typical occupations that are overworked in the event of a disaster. This review suggests that for public servants, the resilience of previous individuals may have affected their PTSD scores. Additionally, exposure to strong complaints from residents and others was raised as a risk of depression in actual practice: it was also found that criticism from local residents had a strong correlation with PTSD and mental stress. Based on these findings, it is important to recognize public servants, especially those who deal directly with the residents and those who are exposed to criticism, as high-risk groups for depression and to establish and have ready a support system in advance.

It should also be noted that public servants themselves may be victims. In particular, those who have lost their relatives, have severely damaged homes, or have been forced to change places of residence have been suggested as being at high risk for mental fatigue: a previous paper has shown that those with these risk factors are at increased risk for PTSD³¹⁾. In the event of a disaster, attention must be paid not only to the work environment of public servants, but also to changes in the personal living environment. It was found that good communication in the workplace and securing of holidays are important factors for reducing the mental load of public servants in the event of a disaster, similar to healthcare professionals.

Emergency professionals

This review has shown that fatigue is a factor to consider, even among emergency professionals, suggesting that those who are tired or fatigued often have a high risk of depression. Additionally, emergency professionals found that, like other occupations, their resilience before dispatch was a factor in reducing risks, such as depression. The harsh living conditions of the responders themselves, for example camping in shelters, were also shown to be a factor in mental stress.

Furthermore, emergency professionals may engage in work directly related to corpses, and those who did were suggested to be at higher risk of depression. This finding is consistent with previous papers, such as a meta-analysis paper by Maslow et al., which focused on military personnel³²⁾.

The review also suggested that emergency professionals are impacted less than other occupations by disasters: it is inferred that this is due to differences in experiences, such as usual emergency response, as a previous paper suggested that groups with less experience in rescue operations were impacted more than experienced groups³³⁾. The mental load varies to different degrees depending on the type of job, so appropriate support is considered necessary.

Although all papers in this study emphasized the need for mental health care, we could not find out any reports that discussed their effective support systems. In the event of a disaster, care for patients and local residents is the main task at hand, and first responders are also invested as resources for the care. In the context of mental stress during disasters, previous papers have suggested that social support is effective in relieving pain after a disaster³⁴⁾. Therefore, it is necessary to rely on the support of others for first responders. In the event of a disaster, support for the victims is given priority, and the care for first responders might be postponed. For example, although the Disaster Psychiatric Assistance Team has been formed to support the health and medical functions of local governments³⁵⁾, the priority is to maintain the health insurance function for the residents. Therefore, it is considered difficult to direct such resources to the care of first responders due to priority issues and specialty issues. Ensuring the health of disaster response staff is important for residents and patients through continued disaster response. Therefore, it is necessary to consider creating an organization that can provide support for the staff, such as medical workers, public servants, and emergency professionals.

The Incident Command System (ICS), which has been standardized in the United States, is a good reference point for such a crisis management support system. In recent years, the need for ICS has been emphasized in Japan, and some organizations are considering implementing ICS as their crisis management systems³⁶⁾.

Regardless of the type of disaster or industry, the establishment of the system can be applied to a variety of organizations, as the basic organizational structure of ICS is the same. In the United States, a safety officer is assigned as one of the command staffs within ICS and is responsible for the overall safety and health of first responders. In Japan as well, ensuring roles of the safety officers within emergency response organizations is extremely important to prevent oversight of occupational health management during a crisis response.

Limitations

The limitation of this study was that it did not include case reports. Many case reports contain insights and approaches that are informative for the care for first responders. Depending on the organization, the support structure for first responders needs to be flexibly arranged. Therefore, it is desirable to review and publish case reports in order to aim for better support for first responders in the future.

Conclusion

Regarding the health problems of workers during the Great East Japan Earthquake, reports concentrated on healthcare workers, civil servants, and emergency professionals. The major health disorders studied were PTSD and depression. Although the common feature was that workers responding to disasters were the subject of various studies, it was observed that there were some differences and characteristics in the mental effects after disaster. When a disaster occurs, attention should be paid not only to the victims, but also to workers who are in the process of responding. In particular, it is considered necessary to establish some kind of support system for workers who are considered to have risk factors for mental illness, and as disasters are inevitable, countries should have these support systems established and ready.

Author Contributions

K.N. and K.M. conceptualized and designed the study; K.N. and K.M. selected and reviewed the papers; K.N. led the writing; T.S. and K.M. critically reviewed the manuscript.

Conflict of interest

The authors declare no conflicts of interest associated with this manuscript.

Funding

This study was funded by a Health Labour Sciences Research Grant.

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