Policing/Incarceration
Epidemiology of suicide in prisons in Japan Naohiro Yonemoto* Naohiro Yonemoto
Background: The problem of suicide in prison facilities such as prisons and jails, and after release, has been the topic of many research reports from Europe and the United States. It is internationally recognized as a high-risk population for suicide. However, there are few research reports from outside Europe and the United States. This study reports on the epidemiology of suicide in prisons in Japan.
Methods: Suicide rates (per 100,000) were calculated and examined for annual trends and summarized background of suicides. The number of suicides and the denominator, the number of persons institutionalized, was taken from the official statistics, National Criminal Statistics (1952-2022; 1990-2022 for males and females) in Japan.
Results: The annual trend results showed that for the period 1952-2020, the suicide rate varied considerably from year to year (min 5.5 – max 46.8) In the period 2010-2022, there were 184 suicides, with a minimum suicide rate of 5.9 and a maximum rate of 31.8. The background of the suicides was 89% male and 10% female. Age was 9% in their 20s, 26% in their 30s, 34% in their 40s, 12% in their 50s, 13% in their 60s, and 5% in their 70s, respectively. Sixty percent were prisoners and 37% were jailed.
Conclusion: The epidemiology of suicide in prisons in Japan was presented. Although persons in prisons are a special group and environment, and comparisons might be difficult, there were some years when the suicide rate was higher and some years when it was lower than that of the general population in Japan. Yearly trends were very different from those of the trend of total in Japan, and there was no association with Japan’s overall suicide rate. Because of the large number of males in prisons, there were more male suicides. Compared to Western studies, the suicide rate in Japan was not high.