Overwork-related disorders in Japan: Recent trends and development of a national policy to promote preventive measures

Abstract

Overwork-related disorders, such as cerebrovascular/cardiovascular diseases (CCVD) and mental disorders due to overwork, are a major occupational and public health issue worldwide, particularly in East Asian countries. This report discusses the recent trend of overwork-related disorders in Japan from the perspective of workers' compensated occupational diseases, as well as the development of a national policy for preventive measures against overwork-related disorders in Japan. Recently, the number of claimed and compensated cases of occupational mental disorders has increased substantially, particularly among young workers, as compared to those of occupational CCVD. In response to these situations and action from society, the Japanese Government passed the "Act on Promotion of Preventive Measures against Karoshi and Other Overwork-Related Health Disorders" in June 2014 to develop a national initiative towards the prevention of overwork-related disorders. Changes in the trend of overwork-related disorders in Japan under a legal foundation and an initiative by the central government should be closely monitored so that other countries can benefit from the experiences.

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OVERWORK-RELATED DISORDERS PREVENT ION POLICY IN JAPAN 293
*To whom correspondence should be addressed.
E-mail: yamat.fw@gmail.com
©2017 National Institute of Occupational Safety and Health
Industrial Health 2017, 55, 293–302 Country Report
This is an open-access article distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives (by-nc-nd) License.
Introduction
Overwork-related disorders, including karoshi (i.e.,
death by cerebrovascular and cardiovascular diseases
(CCVD) due to overwork) and karojisatsu (i.e., suicide
due to overwork), constitute a major occupational and
public health issue worldwide1), particularly in East Asian
countries2), including Japan3). In 2015, the average annual
Overwork-related disorders in Japan: recent trends
and development of a national policy to promote
preventive measures
Takashi YAMAUCHI1*, Toru YOSHIKAWA1, Masahiro TAKAMOTO2, Takeshi SASAKI1,
Shun MATSUMOTO1, Kotaro KAYASHIMA1, Tadashi TAKESHIMA3 and
Masaya TAKAHASHI1
1Research Center for Overwork-Related Disorders, National Institute of Occupational Safety and Health, Japan
2College of Education, Yokohama National University, Japan
3Kawasaki City Center for Mental Health and Welfare, Japan
Received November 10, 2016 and accepted January 23, 2017
Published online in J-STAGE January 31, 2017
Abstract: Overwork-related disorders, such as cerebrovascular/cardiovascular diseases (CCVD)
and mental disorders due to overwork, are a major occupational and public health issue worldwide,
particularly in East Asian countries. This report discusses the recent trend of overwork-related dis-
orders in Japan from the perspective of workers’ compensated occupational diseases, as well as
the development of a national policy for preventive measures against overwork-related disorders in
Japan. Recently, the number of claimed and compensated cases of occupational mental disorders has
increased substantially, particularly among young workers, as compared to those of occupational
CCVD. In response to these situations and action from society, the Japanese Government passed the
“Act on Promotion of Preventive Measures against Karoshi and Other Overwork-Related Health
Disorders” in June 2014 to develop a national initiative towards the prevention of overwork-related
disorders. Changes in the trend of overwork-related disorders in Japan under a legal foundation
and an initiative by the central government should be closely monitored so that other countries can
benet from the experiences.
Key words: Cardiovascular diseases, Cerebrovascular diseases, Japan, Mental disorders, National
strategies, Overwork, Work stress
working hours among employed people in Japan was
1,938.6 h4). On the other hand, regardless of gender, the
proportion of workers who were working 49 h or more per
week in Japan in 2014 (30.0% in men and 9.7% in women)
was higher than that in western developed countries5, 6),
suggesting that long working hours are more prevalent in
Japan. In addition, whereas CCVD and mental disorders
attributed to heavy workloads or stressful work events are
considered compensable occupational diseases by work-
ers’ compensation insurance systems in Japan, Korea, and
Taiwan, the number of compensated cases and these trends
are dierent2).

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Industrial Health 2017, 55, 293–302
According to the National Police Agency of Japan7),
24,025 people died by suicide in Japan in 2015 and, of these
suicide completers, reasons for suicide could be deter-
mined in 17,981 (74.8%). Among those, 2,159 (12.0%)
completed suicide due to “work-related issues,” including
suicidal cases due to “exhaustion due to overwork” (i.e.,
karojisatsu). Recently, suicide rates due to work-related
issues, such as stress involved in long working hours and
heavy workloads, have increased among people aged 20 to
29 yr8). Furthermore, as compared to occupational CCVD,
occupational mental disorders have been compensated
more frequently among young employees in Japan9).
In the present paper, we aimed to discuss the recent trend
of overwork-related disorders in Japan from the perspec-
tive of workers’ compensated occupational diseases (i.e.,
CCVD and mental disorders) due to overwork, as well as
the development of a national policy for the promotion of
preventive measures against overwork-related disorders in
Japan.
Compensated Occupational CCVD and
Mental Disorders in Japan
To our knowledge, the rst reported case of overwork-
related disorders in Japan occurred in 1969, which was a
case of death by stroke10, 11). In addition, the rst case of
occupational mental disorders was compensated in 198412).
Following changes in the awareness of overwork-related
disorders in society and decisions made in the suits, since
1988, the Ministry of Health, Labour and Welfare (MHLW)
of Japan has provided the annual number of cases of both
claimed and compensated occupational CCVD and mental
disorders9, 13).
Figure 1-(a) shows the trend of claimed and compen-
sated cases of occupational CCVD in Japan between scal
years 1988 and 20159, 13). In 2002, the number of compen-
sated occupational CCVD cases increased sharply. Over
the last three scal years, nearly 800 claims for compensa-
tion of occupational CCVD have been made and, of these,
about one third were compensated.
The sharp increase in the number of compensated CCVD
cases in 2002 may be due to the relaxation of the denition
of heavy workloads in the amendment of certication cri-
teria by the MHLW in December 20012, 3). Regarding this
amendment, the expert committee on the criteria for com-
pensation of occupational CCVD, which was organized by
the MHLW, published a report on the association between
overwork and occupational CCVD in November 2001.
Based on this report, the standards of overtime working
Fig. 1-(a). Number of claimed and compensated cases of occu-
pational cardiovascular disease, FY1988– FY2015.
0%
20%
40%
60%
80%
100%
0
200
400
600
800
1,000
1,200
1,400
1,600
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
2010
2012
2014
Number of cases
Fiscal year
Compensation rate (%) Claimed cases
Compensated cases
0%
20%
40%
60%
80%
100%
0
200
400
600
800
1,000
1,200
1,400
1,600
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
2010
2012
2014
Number of cases
Fiscal year
Compensation rate (%) Claimed cases
Compensated cases
Fig. 1-(b). Number of claimed and compensated cases of occu-
pational mental disorders, FY1988 – FY2015.
0%
20%
40%
60%
80%
100%
0
200
400
600
800
1,000
1,200
1,400
1,600
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
2010
2012
2014
Number of cases
Fiscal year
Compensation rate (%) Claimed cases
Compensated cases
0%
20%
40%
60%
80%
100%
0
200
400
600
800
1,000
1,200
1,400
1,600
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
2010
2012
2014
Number of cases
Fiscal year
Compensation rate (%) Claimed cases
Compensated cases
hours for the compensation of occupational CCVD were
established in a more quantitative manner as follows: (1)
overtime working hours of more than 100 h per month for
the past month before the onset of CCVD, and (2) over-
time working hours of more than 80 h per month for the

OVERWORK-RELATED DISORDERS PREVENT ION POLICY IN JAPAN 295
past 2 to 6 months before the onset of CCVD3).
Figure 1-(b) shows the trend of claimed and compen-
sated cases of occupational mental disorders in Japan
between scal years 1988 and 20159, 13). In 1999, the num-
ber of applications for compensation jumped sharply, pos-
sibly due to the establishment of the guideline for com-
pensation of occupational mental disorders by the MHLW.
Since 1999, both the number of claimed and compensated
cases have increased substantially. Compensation rate (the
number of compensated cases divided by the total number
of claims) has also increased from 9.0% in 1999 to 29.3%
in 2002, and has remained at about 30% in recent years.
As shown in Fig. 2, the proportion of suicidal cases
among those who had claimed compensation for occupa-
tional mental disorders was 60% in 1999. Since 1999, the
proportion has substantially decreased due to the dramatic
increase in the total number of claimed cases for compen-
sation and, after 2007, it has remained at about 15%. Sim-
ilarly, the proportion of suicidal cases among those who
were determined to be compensated decreased after 1999,
and it has remained at nearly 20% (Fig. 3).
In 2002, the MHLW launched the rst comprehensive
program for the prevention of health impairment due to
overwork12). It included the following three major focus
areas: (1) reduction of overtime work to 45 h or less per
month, (2) introduction of medical examinations for all
workers, and (3) oer of consultation with and health guid-
ance by a doctor for those who work long hours3, 10). In
addition, the MHLW have implemented some preventive
measures regarding mental health promotion in the work-
place and prevention of workplace bullying and power
harassment14).
However, these programs and eorts by the Government
of Japan to prevent overwork-related disorders may not
have been successful in reducing overwork-related disor-
ders. As argued in previous literature10), that may be due
to (1) the attitudes among the Japanese workers towards
long working hours, (2) the complexity of risk factors
for overwork-related disorders other than long working
hours and work environment, such as shift work, busi-
ness practice, and lifestyle, and (3) low awareness of the
impact of long working hours on health among the public.
In terms of working hours, whereas average annual work-
ing hours among workers (including part-time workers)
in Japan have gradually decreased from 1,920 h in 1993
to 1,734 h in 2015, those among full-time workers have
remained at approximately 2,000 h14). Furthermore, despite
the increase in awareness of overwork-related disorders in
society and the number of cases of occupational disorders,
a detailed analysis of the state of overwork-related disor-
ders in Japan, particularly that in terms of medical diagno-
sis and industry, had not been carried out.
Fig. 3. Proportion of suicide cases among the compensated
cases of occupational mental disorders between scal years
1988 and 2015.
0%
20%
40%
60%
80%
100%
0
100
200
300
400
500
600
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
2010
2012
2014
Number of cases
Fiscal year
Proportion of suicide case (%)
Compensated cases of mental disorders
Compensated cases of suicide
Fig. 2. Proportion of suicide cases among the claimed cases
of occupational mental disorders claimed between scal years
1988 and 2015.
0%
20%
40%
60%
80%
100%
0
200
400
600
800
1,000
1,200
1,400
1,600
1988
1990
1992
1994
1996
1998
2000
2002
2004
2006
2008
2010
2012
2014
Number of cases
Fiscal year
Proportion of suicide case (%)
Claimed cases of mental disorders
Claimed cases of suicide

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Development of National Prevention Strate-
gies for Overwork-related Disorders in Japan
In response to the situations regarding overwork-related
disorders described above and action from relevant people
and organizations, including family members of those who
died by overwork-related disorders, lawyers, and person-
nel of non-prot organizations, with more than 500,000
signatories among the general public, a cross-party group
of lawmakers of the National Diet of Japan was established
to call for a legislation regarding prevention of overwork-
related disorders13). Subsequently, the cross-party group
submitted a bill regarding the promotion of preventive
measures against overwork-related disorders to the Diet.
In June 2014, the Japanese Government passed the “Act
on Promotion of Preventive Measures against Karoshi and
Other Overwork-Related Health Disorders” to develop a
national initiative of prevention of overwork-related dis-
orders15). The Act was enacted in November 2014. In the
Act, the term “overwork-related disorders” was dened to
include all of the following outcomes: (1) death by CCVD
due to overwork, (2) suicide death following an onset of
mental disorders due to psychological stress at work, and
(3) CCVD due to overwork and mental disorders due to
psychological stress at work. It is important to note that
the term “overwork-related disorders” dened in the Act
includes both fatal and non-fatal outcomes. Subsequently,
in July 2015, the “Principles of Preventive Measures
against Overwork-Related Disorders” were established
under the Act.
The aims of the Act are to clarify the responsibili-
ties of the state to promote preventive measures against
overwork-related disorders, including a submission of
the annual report on the state of and prevention policies
regarding overwork-related disorders to the Diet, and to
contribute to realizing a society where people can work
healthily and actively with an adequate work – life balance.
The basic principles of the Act are that (1) research on
overwork-related disorders should be conducted to clarify
the current state of overwork-related disorders in Japan and
to promote preventive measures against overwork-related
disorders, (2) preventive measures should be implemented
based on the increase in awareness of overwork-related
disorders among the public, and (3) comprehensive pre-
vention strategies against overwork-related disorders,
which involve central and local governments, employers,
and other relevant organizations, are needed.
The Act designates November, which includes the
“Labor Thanksgiving Day” in Japan (November 23), as
the “Month for Awareness of Prevention of Overwork-
Related Disorders”, in order to promote public awareness
of overwork-related disorders. Furthermore, under the Act,
the MHLW established the “Council on Promotion of Pre-
ventive Measures against Overwork-Related Disorders”.
The Council is a regular consultative meeting composed
of representatives of (1) those who have suered from
overwork-related disorders and their family members, (2)
family members of those who died by overwork-related
disorders, (3) employees, (4) employers, and (5) academic
experts. As of September 30, 2016, the MHLW has hosted
six Councils (two in scal year 2014 and four in 2015).
The main theme of the Councils was the content of a draft
Table 1. Objectives of the Principles of Preventive Measures against Overwork-Related Disorders
1) To promote research on overwork-related disorders and publish the ndings
1-1) To analyze the state of compensated and non-compensated cases of overwork-related disorders
1-2) To investigate the background factors of overwork-related disorders from the perspective of epidemiology and labor and social sciences
2) To increase awareness of overwork-related disorders
2-1) To increase awareness of overwork-related issues among the public and that of working conditions among high school and university students
2-2) To increase awareness of issues regarding long working hours, health disorders due to overwork, mental healthcare in the workplace, and
power harassment at work (workplace bullying)
2-3) To promote reviewing working style and taking paid vacation among workers
2-4) To promote preventive measures based on business practice
2-5) To increase awareness of overwork-related issues among public employees
3) To develop a counselling service system
3-1) To set up face-to-face, telephone, or e-mail counselling service system on working conditions and health management
3-2) To train and secure human resources (e.g., industrial physicians, occupational health and labor management personnel)
3-3) To set up counselling service system for public employees
4) To support the activities of private sectors
4-1) To support activities and events by private organizations, including symposia on the promotion of preventive measures against overwork-
related disorders
4-2) To disseminate activities of private organizations towards the public

OVERWORK-RELATED DISORDERS PREVENT ION POLICY IN JAPAN 297
of the Principles.
Under the Act, the Cabinet adopted the “Principles of
Preventive Measures against Overwork-Related Disor-
ders” in July 2015. The Principles provided a practical
framework for preventive measures against overwork-
related disorders (Table 1). Following the statement of the
Act, the Principles established the following four major
objectives to be implemented by the Japanese Govern-
ment: (1) to promote research on overwork-related disor-
ders and publish the ndings, (2) to increase awareness of
overwork-related disorders, (3) to develop a counselling
service system, (4) to support the activities of private sec-
tors.
According to the MHLW14), the total national budget for
preventive measures against overwork-related disorders
(promotion of research, increasing the awareness, develop-
ment of counselling service, and support for private sec-
tors) was 5.529 billion JPY in scal year 2015 and 7.435
billion JPY in scal year 2016, respectively (approxi-
mately 1 USD = 120 JPY in October 2015).
Analysis of Details about the State of Over-
work-related Disorders under the Legal
Foundation
Following the enactment of the Act in November 2014,
the Research Center for Overwork-Related Disorders
(RECORDS) was established within the National Insti-
tute of Occupational Safety and Health, Japan (JNIOSH).
To investigate the current situations regarding overwork-
related disorders, the RECORDS collected compensation
claims of recognized cases for occupational CCVD and
mental disorders from January 2010 through March 2015
and conducted a detailed analysis to characterize the back-
ground factors and medical diagnoses relevant to those
disorders. Here, we describe the critical results, comparing
the state between the cases of CCVD and those of mental
disorders. For the ndings shown below, ethical approval
was obtained from the Institutional Review Board of the
National Institute of Occupational Safety and Health,
Japan (No. H2708).
Gender and Age
As shown in Fig. 4-(a) and Fig. 4-(b)16), among those
who were determined to be compensated for having
occupational CCVD and mental disorders between Janu-
ary 2010 and March 2015, 95.6% (1,495/1,564) of the
compensated CCVD cases were male, whereas 68.7%
Fig. 4-(a). Distribution of compensated cases of occupational
cardiovascular disease by age between January 2010 and
March 2015.
0%
10%
20%
30%
40%
<30 30-39 40-49 50-59 60+
Proportion of cases (%)
Age group
Men (n=1,495) Women (n=69)
Fig. 4-(b). Distribution of compensated cases of occupational
mental disorders by age between January 2010 and March
2015.
0%
10%
20%
30%
40%
<30 30-39 40-49 50-59 60+
Proportion of cases (%)
Age group
Men (n=1,372)Women (n=625)
(1,372/1,997) of the cases of compensated mental disor-
ders were male.
As compared to the age distribution of the onset of com-

T YAMAUCHI et al.
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Industrial Health 2017, 55, 293–302
pensated occupational CCVD, occupational mental dis-
orders were compensated more frequently among young
people, particularly those aged 30 to 39 yr. As depicted
in Fig. 4-(b), 50.9% of male compensated cases of mental
disorders and 61.0% of female cases were their 20s or 30s.
The mean age of the onset of compensated CCVD was 49.3
(SD, 9.7) among men and 49.4 (SD, 12.6) among women,
whereas that of compensated mental disorders was 40.0
(SD, 11.3) among men and 36.9 (SD, 11.9) among women.
Working Hours and Work Events
Figure 5 shows the distribution of overtime hours
among those who were compensated in scal years 2014
and 20159). As depicted in Fig. 5, 64.8% of compensated
occupational CCVD cases were conrmed having over-
time hours between 80 and 119 h per month prior to the
onset of occupational CCVD. On the other hand, 38.3%
of compensated cases of mental disorders were con-
rmed having overtime working hours of less than 60 h
per month before the onset, and 17.2% were compensated
due to work-related factors other than long working hours,
including exposure to extremely stressful work events,
such as severe sexual harassment/violence or accidents in
the workplace16).
Job Area/Type
Tables 2 and 3 depict the distribution of compensated
occupational CCVD and mental disorders, respectively,
by gender and job area between January 2010 and March
201516). Regarding occupational CCVD (Table 2), among
men, 30.7% of compensated cases were in “transport and
postal activities,” followed by “wholesale and retail trade”
and “manufacturing.” In terms of compensated occupa-
tional mental disorders (Table 3), among men, “manufac-
turing” had the largest number of compensated workers,
followed by “wholesale and retail trade” and “transport
and postal activities.” Notably, among women, 28.8% of
compensated cases of occupational mental disorders were
in “medical, health and welfare.” As suggested in previ-
ous literature17), female healthcare professionals, such as
nurses in mental health care or caregivers for the elderly,
may be more frequently exposed to work-related trau-
matic events, such as physical assaults and violence from
patients and service users. However, regardless of the type
of overwork-related disorders (i.e., occupational CCVD
or mental disorders), workers in these job areas might not
be necessarily compensated more frequently compared to
those in other job areas, given the total number of people
employed in each job area/industry as the denominator18).
There are some limitations to interpret the values shown
Fig. 5. Distribution of compensated cases of occupational cardiovascular disease and mental disorders by overtime hours in scal
years 2014 and 2015.
0%
10%
20%
30%
40%
50%
<60 60-79 80-99 100-119 120-139 140-159 160+ Other factors
Proportion of cases (%)
Overtime hours
Occupational CCVD (n=528)Occupational mental disorders (n=969)

OVERWORK-RELATED DISORDERS PREVENT ION POLICY IN JAPAN 299
Table 2. Distribution of compensated cases of cerebrovascular/cardiovascular disease by job category
Men Women
No. of casesa)
No. of
employee
population
(10,000)b,c)
No. of cases
per 1 milliond)
No. of casesa)
No. of
employee
population
(10,000)b,c)
No. of cases
per 1 milliond)
Job category (alphabetical order)e) n % n % n % n %
Accommodations, eating, and drinking services 104 7.0% 529 4.0% 19.7 10 14.5% 986 8.9% 1.0
Agriculture and forestry 6 0.4% 148 1.1% 4.1 1 1.4% 111 1.0% 0.9
Compound services 6 0.4% 147 1.1% 4.1 1 1.4% 98 0.9% 1.0
Construction 162 10.8% 1,448 10.9% 11.2 0 0.0% 243 2.2% 0.0
Education, learning support 23 1.5% 613 4.6% 3.8 2 2.9% 704 6.4% 0.3
Electricity, gas, heat supply, and water 1 0.1% 134 1.0% 0.7 0 0.0% 19 0.2% 0.0
Finance and insurance 9 0.6% 333 2.5% 2.7 1 1.4% 400 3.6% 0.3
Fisheries 14 0.9% 26 0.2% 53.8 0 0.0% 6 0.1% 0.0
Information and communications 46 3.1% 610 4.6% 7.5 5 7.2% 215 2.0% 2.3
Living-related, personal, and amusement services 33 2.2% 332 2.5% 9.9 4 5.8% 523 4.7% 0.8
Manufacturing 186 12.4% 3,263 24.5% 5.7 7 10.1% 1,359 12.3% 0.5
Medical, health, and welfare 38 2.5% 709 5.3% 5.4 11 15.9% 2,563 23.3% 0.4
Mining and quarrying of stone and gravel 0 0.0% 12 0.1% 0.0 0 0.0% 3 0.0% 0.0
Real estate and goods rental and leasing 28 1.9% 236 1.8% 11.9 0 0.0% 140 1.3% 0.0
Scientic research, professional, and technical
services 44 2.9% 417 3.1% 10.6 3 4.3% 249 2.3% 1.2
Services, N.E.C. 121 8.1% 1,091 8.2% 11.1 4 5.8% 815 7.4% 0.5
Transport and postal activities 459 30.7% 1,272 9.5% 36.1 6 8.7% 292 2.6% 2.1
Wholesale and retail trade 215 14.4% 2,005 15.0% 10.7 14 20.3% 2,296 20.8% 0.6
Total 1,495 100% 13,325 100% 11.2 69 100% 11,022 100% 0.6
a) Total number of cases that were determined to be compensated between January 2010 and March 2015. This column includes the cases that were
claimed to workers’ compensation before December 2009.
b) Data from the Labour Force Survey, Ministry of Internal Aairs and Communications of Japan.
c) Total population of employees (annual average) in Japan between January 2010 and December 2014. These gures include both full-time and part-time
employees.
d) Due to the unavailability of data on the population of employees between January 2015 and March 2015, the compensation rates in this column are
slightly higher than the actual value.
e) Public employees and central and local government ocers are not included.
in Tables 2 and 3. For instance, due to the unavailability
of data on the population of employees between January
2015 and March 2015, the compensation rates are slightly
higher than the actual value.
Medical Diagnoses
Table 4 shows the distribution of diagnoses among com-
pensated cases of occupational CCVD by gender between
January 2010 and March 201516). While 60.5% of male
compensated cases had been diagnosed as having cerebro-
vascular diseases, particularly intracerebral hemorrhage,
91.3% of female compensated cases had been diagnosed
having cerebrovascular diseases.
Table 5 summarizes the distribution of diagnoses among
compensated cases of occupational mental disorders by
gender between January 2010 and March 201516). Notably,
59.7% of male compensated cases had been diagnosed as
having mood (aective) disorders. Among women, 73.0%
of compensated cases had been diagnosed having neurotic,
stress-related, or somatoform disorders, particularly post-
traumatic stress disorder (PTSD).
Conclusion
In the current paper, we briey analyzed the characteris-
tics of compensated occupational CCVD and mental disor-
ders due to overwork or psychological stress at work. Over
the past decade, the number of claims, as well as that of
compensation, of occupational mental disorders have been
substantially increasing, as compared to those of occupa-
tional CCVD. Notably, among the cases of compensated
occupational mental disorders, approximately 50% of
male and 60% of female cases were in their 20s or 30s.

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Table 3. Distribution of compensated cases of mental disorders by job category
Men Women
No. of casesa)
No. of
employee
population
(10,000)b,c)
No. of cases
per 1 milliond)
No. of casesa)
No. of
employee
population
(10,000)b,c)
No. of cases
per 1 milliond)
Job category (alphabetic order)e) n % n % n % n %
Accommodations, eating, and drinking services 87 6.3% 529 4.0% 16.4 48 7.7% 986 8.7% 4.9
Agriculture and forestry 15 1.1% 148 1.1% 10.1 2 0.3% 111 1.0% 1.8
Compound services 10 0.7% 147 1.1% 6.8 7 1.1% 98 0.9% 7.1
Construction 138 10.1% 1,448 10.9% 9.5 11 1.8% 243 2.2% 4.5
Education, learning support 32 2.3% 613 4.6% 5.2 25 4.0% 704 6.2% 3.6
Electricity, gas, heat supply, and water 12 0.9% 134 1.0% 9.0 1 0.2% 19 0.2% 5.3
Finance and insurance 23 1.7% 333 2.5% 6.9 30 4.8% 400 3.5% 7.5
Fisheries 6 0.4% 26 0.2% 23.1 0 0.0% 6 0.1% 0.0
Information and communications 97 7.1% 610 4.6% 15.9 28 4.5% 215 1.9% 13.0
Living-related, personal, and amusement services 30 2.2% 332 2.5% 9.0 15 2.4% 523 4.6% 2.9
Manufacturing 290 21.1% 3,263 24.5% 8.9 59 9.5% 1,359 12.0% 4.3
Medical, health, and welfare 51 3.7% 709 5.3% 7.2 179 28.8% 2,563 22.7% 7.0
Mining and quarrying of stone and gravel 3 0.2% 12 0.1% 25.0 0 0.0% 3 0.0% 0.0
Real estate and goods rental and leasing 39 2.8% 236 1.8% 16.5 13 2.1% 140 1.2% 9.3
Scientic research, professional, and technical
services 70 5.1% 417 3.1% 16.8 22 3.5% 249 2.2% 8.8
Services, N.E.C. 100 7.3% 1,091 8.2% 9.2 45 7.2% 815 7.2% 5.5
Transport and postal activities 176 12.8% 1,272 9.5% 13.8 38 6.1% 292 2.6% 13.0
Wholesale and retail trade 193 14.1% 2,005 15.0% 9.6 97 15.6% 2,296 20.3% 4.2
Total 1,372 100% 13,325 100% 10.3 620 100% 11,022 100% 5.6
a) Total number of cases that were determined to be compensated between January 2010 and March 2015. This column includes the cases that were
claimed to workers’ compensation before December 2009.
b) Data from the Labour Force Survey, Ministry of Internal Aairs and Communications of Japan.
c) Total population of employees (annual average) in Japan between January 2010 and December 2014. These gures include both full-time and part-time
employees.
d) Due to the unavailability of data on the population of employees between January 2015 and March 2015, the compensation rates in this column are
slightly higher than the actual value.
e) Public employees and central and local government ocers are not included.
Table 4. Distribution of diagnosis of occupational cerebrovascular/
cardiovascular disease by gender
Men
(n = 1,495)
Women
(n = 69)
nSD/% nSD/%
Age of onset (Mean, SD) 49.3 9.7 49.4 12.6
Cerebrovascular diseases
Intracerebral hemorrhage 419 28.0% 28 40.6%
Subarachnoid hemorrhage 261 17.5% 28 40.6%
Cerebral infarction 221 14.8% 7 10.1%
Hypertensive encephalopathy 4 0.3% 0 —
Cardiovascular diseases
Myocardial infarction 267 17.9% 1 1.4%
Cardiac arrest 220 14.7% 4 5.8%
Dissecting aneurysm 81 5.4% 1 1.4%
Angina pectoris 19 1.3% 0 —
Other diseases (e.g., epilepsy) 3 0.2% 0 —
Table 5. Distribution of diagnosis of occupational mental disorders
by gender
Men
(n = 1,373)
Women
(n = 627)
nSD/% nSD/%
Age of onset (Mean, SD) 40.0 11.3 36.9 11.9
F3 (Mood (aective) disorders) 820 59.7% 169 27.0%
F32 (Depressive episode) 716 52.1% 151 24.1%
Other F3 104 7.6% 18 2.9%
F4 (Neurotic, stress-related and somato-
form disorders) 540 39.3% 458 73.0%
F43.0 (Acute stress reaction) 39 2.8% 61 9.7%
F43.1 (Post-traumatic stress disorder) 145 10.6% 163 26.0%
F43.2 (Adjustment disorders) 228 16.6% 129 20.6%
Other F4 128 9.3% 105 16.7%
Other mental disorders 13 0.9% 0 —

OVERWORK-RELATED DISORDERS PREVENT ION POLICY IN JAPAN 301
These ndings suggest the importance of promoting men-
tal health-related support for young employees, as well as
increasing awareness of working conditions among stu-
dents.
In scal year 2015 (i.e., the rst full scal year after the
Act was enacted in November 2014), the number of claims
for workers’ compensation of both occupational CCVD
and mental disorders in Japan increased slightly from the
previous year (Fig. 1-(a) and Fig. 1-(b)). This may be due
to increased awareness of overwork-related disorders and
workers’ compensation system for occupational CCVD
and mental disorders, because the enactment of the Act,
along with the recent situation regarding overwork-related
disorders, were widely reported by the media in Japan.
The term karoshi rstly appeared in Japan in the late
1970s. To our knowledge, Japan was the rst country to
pass a law specically focusing on comprehensive pre-
ventive measures against overwork-related disorders.
Overwork-related disorders have been a major occupa-
tional and public health issue in both developed and devel-
oping countries. Thus, experience in Japan can provide
other countries with useful information on developing a
national preventive policy against overwork-related disor-
ders. Changes in the trend of overwork-related disorders
in Japan under a legal foundation and an initiative by the
central government should be closely monitored, so that
other countries can benet from the experiences. Addition-
ally, the long-term eect of preventive measures based on
the Act and the Principles (i.e., preventive eorts regarding
increasing the awareness, development of counselling ser-
vice, and support for private sectors) should be evaluated.
Acknowledgements
We would like to thank Dr. Shigeki Koda, Deputy
Director-General of the National Institute of Occupational
Safety and Health, Japan, for providing administrative
support and important discussion. We also thank the sta
at the Research Center for Overwork-Related Disorders,
National Institute of Occupational Safety and Health,
Japan, for their support with data collection.
This work was supported by the Industrial Disease Clin-
ical Research Grants from the Ministry of Health, Labour
and Welfare, Government of Japan (150903-01).
Disclaimer
The content of this paper reects the views of the
authors and does not necessarily reect the views and poli-
cies of the Ministry of Health, Labour and Welfare, Gov-
ernment of Japan, or the National Institute of Occupational
Safety and Health, Japan. The translation of the names of
proper nouns, such as the name of an act, from Japanese
into English language was made by the authors and is not
an ocial translation by the Government of Japan.
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