Abstract
BackgroundIn Japan, a dramatic rise in suicide rates was observed in the 1950s, especially among the younger population, and then the rate decreased rapidly again in the 1960s. The aim of this study was to assess secular trends in method-specific suicides by gender and age in Japan between 1950 and 1975. We paid special attention to suicides by poisoning (solid and liquid substances), and their contribution to dramatic swings in the overall suicide rate in Japan during the 1950s and 1960s.MethodsMortality and population data were obtained from the Vital Statistics of Japan and Statistics Bureau, Ministry of Internal Affairs and Communications in Japan, respectively. We calculated method-specific age-standardized suicide rates by gender and age group (15–29, 30–49, or 50+ years).ResultsThe change in the suicide rate during the research period was larger in males than females in all age groups, and was more marked among people aged 15–29 years compared to those aged 30–49 years and 50 years or over. Poisoning by solid and liquid substances overwhelmingly contributed to the dramatic change in the overall suicide rates in males and females aged 15–49 years in the 1950s and 1960s. For the peak years of the rise in poisoning suicides, bromide was the most frequently used substance.ConclusionsOur results for the 1950s and 1960s in Japan illustrated how assessing secular trends in method-specific suicides by gender and age could provide a deeper understanding of the dramatic swings in overall suicide rate. Although rapid increases or decreases in suicide rates have been also observed in some countries or regions recently, trends in method-specific suicides have not been analyzed because of a lack of data on method-specific suicide in many countries. Our study illustrates how the collection and analysis of method-specific data can contribute to an understanding of dramatic shifts in national suicide rates.
Highlights
In Japan, a dramatic rise in suicide rates was observed in the 1950s, especially among the younger population, and the rate decreased rapidly again in the 1960s
Dramatic changes in overall suicide rates were observed in the 1950s and 1960s, and the overall suicide rates were almost parallel to the poisoning rates during this period
Poisoning by solid and liquid substances overwhelmingly contributed to the dramatic change in the overall suicide rates in males and females aged 15–49 years in the
Summary
In Japan, a dramatic rise in suicide rates was observed in the 1950s, especially among the younger population, and the rate decreased rapidly again in the 1960s. The increased use of pesticides in many agrarian societies during the second half of the 20th century, domestic coal gas in the 1920s and 1930s in the UK, and motor vehicles in the 1970s and 1980s in the UK were associated with an increase in suicides [4,5,6] These findings indicate that analyzing trends in method-specific suicides may help to understand the background of the Yoshioka et al Population Health Metrics (2017) 15:14 recent trends in overall suicides rates in some countries where rapid changes have recently been observed; many countries do not collect data on the methods used in suicide [1]. 76 of the 194 WHO member states reported data on methods of suicide in the WHO mortality database between 2005 and 2011, and this means that the methods used in 72% of global suicides are unclear [1]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
