The Kobe Earthquake and Reduced
Suicide Rate in Japanese Males
S
uicide ranks among the top 10 causes of death for
individuals of all ages in most countries.
1
It is also
among the 2 or 3 leading causes of death for those
aged 15 to 34 years.
1
In the United States, suicide ac-
counts for over 30 000 deaths annually.
2
In Japan, there
are more than 20 000 suicides a year, twice as many as
the number of traffic fatalities.
3
Although suicide is not
a logical response to extreme stress, typical stressors as-
sociated with suicide acts include adverse events in one’s
life.
4
Suicide victims have often encountered more changes
in terms of living conditions, work problems, and hu-
miliating experiences than most of the population.
5
For
example, bereavement involving a close interpersonal re-
lationship in the few years preceding suicide has been
more common among suicide victims than among the
general population.
6
On January 17, 1995, at 5:46 AM, a devastating earth-
quake measuring 7.2 on the Richter scale shook the city
of Kobe, Japan, leaving 3897 people dead, more than
13 000 severely injured, 54 000 houses completely or par-
tially destroyed, and 230 000 people displaced from their
homes. Most of the people in Kobe sustained heavy losses
and many people went through bereavements of one or
more close interpersonal relationships. For the citizens
of Kobe, this earthquake was certainly a very notable stress
or adverse life event. This prompted us to review the sui-
cide rate in Kobe before and after the earthquake.
We observed a significant reduction in the suicide
rate in Kobe in the remainder of 1995. Compared with
the suicide rates in Kobe in the 13 years from 1985 to
1997, the decrease in the suicide rate in 1995 looks quite
apparent. The Figure provides the suicide rate (per
100 000) and population in Kobe during the 10 years
(1985-1994) before the earthquake and also from 1995
to 1997. The data were compiled by the Medical Exam-
iner’s Office of Hyogo Prefecture and published in their
annual reports (the population in Kobe was 1 518 082 in
1994 and 1 423 792 in 1995, a decrease of 6.2%). The rate
suicide rate (per 100 000) of 1995 (12.57 persons per
100 000 people) in total population was the lowest in the
last 52 years (1946-1997), ie, since the conclusion of
World War II. The year 1995 had a significantly lower
suicide rate than the average (16.33 per 100 000) sui-
cide rate of the 10 years before the earthquake (1985-
1994) (x
2
= 7.06, P,.01) and a tendency to decrease com-
pared with the year 1994 (15.08) before the earthquake
(x
2
= 3.25, P,.08). The figure shows that the suicide rate
(1996-1997) gradually returned to average in the 2 years
after the earthquake. Interestingly, as compared with the
average of the 10-year period before the earthquake (21.35
per 100 000 people), only the male suicide rate was sig-
nificantly reduced in 1995 (16.39 per 100 000) (x
2
= 4.52,
P,.05), whereas the female rate was not significantly dif-
ferent. To examine a trend in changes in rates over the
11-year period (1985-1995), using the Bartholomew test,
the rates in the total and female populations showed a
trend toward reduction (x
2
= 29.54, P,.01; x
2
= 19.55,
P,.05, respectively), while the rate for males did not. Of
the male suicides, those in their 30s and 50s particu-
larly showed a reduction in 1995. Also, in 1995 there was
a decrease in the percentage (16.8%) of suicides associ-
ated with falling, specifically jumping from high places,
compared with the average (22.8%) of 10 years prior
(1985-1994), and also the rates observed in 1996 (25.6%)
and 1997 (21.4%).
The effect of major societal upheaval on the sui-
cide rate has been documented. In 1995, Soma-
sundaram and Rajadurai
7
studied the effect of war on the
suicide rate in the biggest town in north Sri Lanka for
10 years from 1980 to 1989. They found a marked drop
in the suicide rate, particularly the male rate, during the
war. The sex difference suggests that adverse life events
may have a differential effect on male and female sub-
jects. In 1993, Lester
8
also reported that suicide rates in
France were lower during years of war than during years
of peace (1826-1913), although female suicides contrib-
uted to the reduced rate. On the contrary, Krug et al
9
re-
cently examined the changes in the suicide rate in the
total population after 4 earthquakes and reported an in-
30
25
20
15
10
0
1.6
1.0
1.2
1.4
0.8
0.6
0.4
0.2
1985
1985
1990 1991 1992 1993 1994 1989 1988 1987 1986 1995 1996 1997
1990 1991 1992 1993 1994 1989 1988 1987 1986 1995 1996 1997
Year
Year
Suicide Rate per 100 000
16.33
The Average
of the Total
Suicide Rate
(1985-1994)
Total
Male
Female
Kobe Earthquake
Jan 17, 1995
Population × 10
6
People
Upper and lower parts of the figure represent the changes in suicide rate per
100 000 people and population in Kobe, Japan, covering 13 years,
respectively. Shaded area shows the years before the earthquake. The dotted
line indicates the average of 10 years (1985-1994) of total suicide rate
(16.33 per 100 000). Compared with 1994, the tendencies were toward lower
total and male suicide rates in 1995 (x
2
=3.35, P,.08; x
2
=3.07, P,.09,
respectively). There were also significant differences between the average of
10 years and 1995 in the total and male suicide rates (x
2
= 7.06, P,.01; x
2
=
4.52, P,.05, respectively).
LETTERS TO THE EDITOR
ARCH GEN PSYCHIATRY/ VOL 56, MAR 1999
282
©1999 American Medical Association. All rights reserved.