Post‐traumatic stress symptoms among medical rescue workers exposed to COVID‐19 in Japan

The novel coronavirus disease (COVID‐19) has spread throughout the world. At an early stage in Japan, health‐care professionals who belong to the Disaster Medical Assistance Team (DMAT) or the Disaster Psychiatric Assistance Team (DPAT) were engaged in rescue activities outside hospitals. DMAT members engaged in quarantine and treatment and DPAT members provided mental health care for people who might have had COVID‐19. This included quarantine and treatment for people infected with COVID‐19 on a cruise ship, the Diamond Princess. ¹ It is well‐known that mental health problems have occurred among health‐care professionals responding to COVID‐19. ² , ³ Previous studies have reported mental health problems and associated factors among health‐care professionals from infectious disease outbreaks. ⁴ , ⁵ , ⁶ , ⁷ However, no studies have examined associated factors with post‐traumatic stress symptoms (PTSS) among health‐care professionals who have been deployed to activities of emerging infectious diseases outside hospitals. The present study examined factors associated with PTSS among DMAT and DPAT members who have been deployed to COVID‐19‐related activities outside hospitals.

DMAT and DPAT are trained medical teams with the mobility to work in an acute phase of disaster. DMAT and DPAT members (physicians, nurses, and operational coordination staff) were dispatched to COVID‐19‐related activities commencing 1 February 2020; DPAT activities ended on 6 March, and DMAT activities ended on 9 March. The recruited participants in this study, including all DMAT and DPAT members who were deployed to COVID‐19‐related activities, met the following inclusion criteria: (i) aged 18 years or older; (ii) native Japanese speaker or non‐native speaker with Japanese conversational abilities; and (iii) physically and psychologically capable of understanding and providing consent for study participation. This cross‐sectional, Internet‐based survey was conducted from 11 March to 2 April 2020. A written guide to this study was posted to the mailing list by the DMAT office or DPAT office. Participants accessed the URL in the written guide, read a detailed explanation of the study, and responded to a consent form and a questionnaire by 2 April. Outcomes of this study were evidence of PTSS. PTSS was assessed by the Impact of Event Scale‐Revised (IES‐R). Independent variables were selected based on previous studies. Peritraumatic distress was assessed by the Peritraumatic Distress Inventory (PDI), and perceived stress specific to the emerging infectious disease was assessed by the Japanese version of Stress‐Related Questions (SRQ). ⁸ The SRQ consists of four factors (anxiety about infection, exhaustion, workload, and feeling of being protected) and includes16 items. ⁵ The validity and reliability of the Japanese version of the IES‐R, the PDI, and the SRQ have been confirmed. ⁵ , ⁹ , ¹⁰ In addition, participants were asked about the variables that were identified in a previous study ⁴ , ⁵ , ⁶ , ⁷ or from our interviews with DMAT and DPAT members as associated factors for PTSS.

This study was ethically approved by the research ethics committee of the Graduate School of Medicine and Faculty of Medicine at the University of Tokyo (No. 2019164NI) and the research ethics committee of the National Hospital Organization Disaster Medical Center (No. 2019–19).

We analyzed the dataset of participants who completed all questions of the self‐report questionnaire. Univariate and multiple linear regression analyses were used to examine the association of independent variables with PTSS. All analyses were conducted using spss Version 22.0 J for Windows (SPSS, Tokyo, Japan).

Among 807 DMAT and DPAT members who were deployed to COVID‐19‐related activities, 414 agreed to participate in this study, and 331 (41.0%) completed all questions. Demographic characteristics are shown in Table S1. Among the participants, 105 (31.7%) had had contact with a COVID‐19 patient during deployment. The results of univariate and multiple linear regression analyses about PTSS in the participants are shown in Table 1. Multiple linear regression analysis showed that anxiety about infection assessed by the SRQ, exhaustion assessed by the SRQ, PDI, and being DMAT members were associated with PTSS. The results of a univariate regression analysis of each PDI item showed that items such as “I felt I might pass out” and “I had difficulty controlling my bowel and bladder” were strongly significantly associated with PTSS (Table S2).

Table 1.

Results of univariate and multiple linear regression analysis in participants (n = 331) for post‐traumatic stress symptoms

	Univariate regression			Multiple linear regression
	β	95%CI	P	β	95%CI	P
Contact with a COVID‐19 patient	0.15	−2.28, 2.59	0.90	−0.49	−2.27, 1.29	0.59
Stress prior to deployment	3.15	0.73, 5.57	0.01	−1.34	−3.24, 0.57	0.17
Adequate food and sleep or rest	−5.01	−7.22, −2.79	<0.001	0.16	−1.70, 2.02	0.87
Experience of stress due to lack of sufficient information sharing	3.85	1.52, 6.18	0.001	0.56	−1.26, 2.37	0.55
Troubles at home after deployment	4.84	2.51, 7.16	<0.001	1.83	−0.01, 3,67	0.05
Troubles at workplace after deployment	5.72	3.46, 7.98	<0.001	0.05	−1.81, 1.90	0.96
Opportunities to hear about deployment activities after deployment	−3.96	−6.31, −1.61	0.001	−1.53	−3.28, 0.20	0.08
SRQ: Anxiety about infection	0.51	0.24, 0.77	<0.001	−0.26	−0.50, −0.03	0.03
SRQ: Exhaustion	1.59	1.26, 1.92	<0.001	0.78	0.42, 1.14	<0.001
SRQ: Workload	1.95	1.29, 2.61	<0.001	−0.03	−0.66, 0.60	0.94
SRQ: Feeling of being protected	−0.92	−1.70, −0.15	0.02	0.27	−0.30, 0.84	0.35
PDI	1.00	0.89, 1.11	<0.001	0.92	0.79, 1.05	<0.001
Age	−0.03	−0.16, 0.10	0.61	0.05	−0.05, 0.14	0.33
Sex	0.04	−2.56, 2.65	0.97	−1.04	−2.90, 0.82	0.27
DMAT (Reference) or DPAT	−1.41	−4.18, 1.36	0.31	−2.14	−4.16, −0.12	0.04
R 2						0.55

Post‐traumatic stress symptoms were assessed by the Japanese version of the Impact of Event Scale‐Revised.

CI, confidence interval; DMAT, Disaster Medical Assistance Team; DPAT, Disaster Psychiatric Assistance Team; PDI, Peritraumatic Distress Inventory; SRQ, Stress‐Related Questions.

[Correction added on 2 September, after first online publication: The P‐value number of ‘Sex’ under ‘Univariate regression’ has been amended.]

Although this study has some limitations, such as modest response rate and cross‐sectional design, the findings of the study suggest that physical exhaustion, peritraumatic distress, and activities during deployment were very important as associated factors for PTSS among medical rescue workers. To prevent mental health problems in health‐care professionals dealing with emerging infectious disease, it is essential to give them enough time for self‐care, including allowing time and physical allowances (such as adequate infection‐protection clothing) to use the bathroom. In addition, health‐care professionals may need to have their mental health checked after deployment, especially when they have had physical contact with potential patients with emerging infectious diseases. However, this needs to be further examined because univariate regression analysis did not show significant associations between being DMAT members and PTSS. These findings could be useful for establishing a system for rescue activities for infectious diseases, including COVID‐19, and for preventing mental health problems among health‐care professionals.

Disclosure statement

The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. All authors declare no relevant conflicts of interest in relation to the subject of the manuscript.

Supporting information

Table S1 Demographic characteristics of participants.

Table S2 Results of univariate regression analysis of each Peritraumatic Distress Inventory item in participants for post‐traumatic stress symptoms.