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Time trends in suicide rates by domestic gas or car exhaust gas inhalation in Japan, 1968–1994

Published online by Cambridge University Press:  14 August 2018

E. Yoshioka Open the ORCID record for E. Yoshioka [Opens in a new window] ,
S. J. B. Hanley  and
Y. Saijo
E. Yoshioka*
Affiliation:
Department of Social Medicine, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
S. J. B. Hanley
Affiliation:
Department of Women's Health Medicine, Hokkaido University Graduate School of Medicine, Sapporo, Hokkaido, Japan
Y. Saijo
Affiliation:
Department of Social Medicine, Asahikawa Medical University, Asahikawa, Hokkaido, Japan
*
Author for correspondence: Eiji Yoshioka, E-mail: [email protected]
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Abstract

Aims

A reduction in the carbon monoxide content of domestic gas and car exhaust gas has been associated with a decrease in gassing suicides in many western countries. In Japan, a reduction in the carbon monoxide content of domestic gas supply began in the early 1970s, and carbon monoxide emissions standards of new passenger cars were significantly strengthened in 1978. However, little is known about the impact of detoxification of these gases on gassing-related suicides in Japan. Therefore, we examined the changing patterns of suicide due to domestic gas or car exhaust gas inhalation by gender and age in Japan between 1968 and 1994.

Methods

Suicide mortality data were obtained from the Vital Statistics of Japan. In this study, age was divided into four groups: 15–24, 25–44, 45–64 and 65+ years. Method of suicide was divided into three groups: domestic gas, car exhaust gas and non-gases. We calculated method-specific age-standardised suicide rates by gender within each of the four age groups. We applied joinpoint regression to the data and quantified the observed changes.

Results

Suicide rates by domestic gas, regardless of gender and age, increased from 1968 to the mid-1970s and then decreased sharply. The proportion of all suicides accounted for by domestic gas was comparatively high in the mid-1970s among females aged 15–24 and 25–44 years, while for other gender-age-groups the proportion of domestic gas suicides remained small, even at the peak. For females aged 15–44 years, the decrease in domestic gas suicides appeared to cause a substantial decrease in overall suicides in this gender/age group. Car exhaust gas was a more common method for males, particularly those aged 25–64 years. Car exhaust gas suicide rates for males aged 25–64 years peaked in the mid-1980s, followed by a sharp decrease.

Conclusions

A reduction in the carbon monoxide content of the domestic gas, which began in the early 1970s in Japan, was associated with a decrease in domestic gas suicides for both genders of all ages. Concerning females aged 15–44 years, a decrease in domestic gas suicides caused a substantial decrease in overall suicides in this gender/age group since the proportion of domestic gas suicides among all suicides combined was comparatively large. However, it remains uncertain whether the introduction of catalytic converters in the 1970s in Japan resulted in a reduction of suicides from car exhaust gas inhalation.

Keywords

Community mental healthepidemiologypopulation surveysocial factorssuicide
Type
Original Articles
Information
Epidemiology and Psychiatric Sciences , Volume 28 , Issue 6 , December 2019 , pp. 644 - 654
Copyright
Copyright © Cambridge University Press 2018 

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References

Ahmad, OB, Boschi-Pinto, C, Lopez, AD, Murray, CJL, Lozano, R and Inoue, M (2001) Age Standardization of Rates: a new WHO standard. Geneva: World Health Organization, 9. Available at http://www.who.int/healthinfo/paper31.pdf (Accessed 13 February 2018).Google Scholar
Amos, T, Appleby, L and Kiernan, K (2001) Changes in rates of suicide by car exhaust asphyxiation in England and Wales. Psychological Medicine 31, 935–939.Google Scholar
Azrael, D and Miller, MJ (2016) Reducing suicide without affecting underlying mental health. In O'Connor, RC and Pirkis, J (eds), The International Handbook of Suicide Prevention, 2nd Edn. Chichester, UK: John Wiley & Sons, Ltd, pp. 637–662.Google Scholar
Burvill, PW (1990) The changing pattern of suicide by gassing in Australia, 1910–1987: the role of natural gas and motor vehicles. Acta Psychiatrica Scandinavica 81, 178–184.Google Scholar
Cantor, CH and Baume, PJM (1998) Access to methods of suicide: what impact? Australian and New Zealand Journal of Psychiatry 32, 8–14.Google Scholar
Chang, SS, Sterne, JAC, Lu, TH and Gunnell, D (2010) ‘Hidden’ suicides amongst deaths certified as undetermined intent, accident by pesticide poisoning and accident by suffocation in Taiwan. Social Psychiatry and Psychiatric Epidemiology 45, 143–152.Google Scholar
Clarke, RV and Lester, D (1987) Toxicity of car exhausts and opportunity for suicide: comparison between Britain and the United States. Journal of Epidemiology and Community Health 41, 114–120.Google Scholar
Gunnell, D, Middleton, N and Frankel, S (2000) Method availability and the prevention of suicide – A re-analysis of secular trends in England and Wales 1950–1975. Social Psychiatry and Psychiatric Epidemiology 35, 437–443.Google Scholar
Gunnell, D, Bennewith, O, Simkin, S, Cooper, J, Klineberg, E, Rodway, C, Sutton, L, Steeg, S, Wells, C and Hawton, K (2013) Time trends in coroners’ use of different verdicts for possible suicides and their impact on officially reported incidence of suicide in England: 1990–2005. Psychological Medicine 43, 1415–1422.Google Scholar
Hepp, U, Ring, M, Frei, A, Rössler, W, Schnyder, U and Ajdacic-Gross, V (2010) Suicide trends diverge by method: Swiss suicide rates 1969–2005. European Psychiatry 25, 129–135.Google Scholar
Hirota, K and Minato, K (2001) Inspection and Maintenance system in Japan. Available at http://www.un.org/esa/gite/iandm/jaripaper.pdf (Accessed 13 February 2018).Google Scholar
Kim, HJ, Fay, MP, Feuer, EJ and Midthune, DN (2000) Permutation tests for joinpoint regression with applications to cancer rates. Statistics in Medicine 19, 335–351.Google Scholar
Kreitman, N (1976) The coal gas story. United Kingdom suicide rates, 1960–71. British Journal of Preventive & Social Medicine 30, 86–93.Google Scholar
Lester, D (1990 a) The effect of the detoxification of domestic gas in Switzerland on the suicide rate. Acta Psychiatrica Scandinavica 82, 383–384.Google Scholar
Lester, D (1990 b) The effects of detoxification of domestic gas on suicide in the United States. American Journal of Public Health 80, 80–81.Google Scholar
Lester, D and Abe, K (1989 a) Car availability, exhaust toxicity, and suicide. Annals of Clinical Psychiatry 1, 247–250.Google Scholar
Lester, D and Abe, K (1989 b) The effect of restricting access to lethal methods for suicide: a study of suicide by domestic gas in Japan. Acta Psychiatrica Scandinavica 80, 180–182.Google Scholar
Ministry of Health Labour and Welfare (1999) Vital Statistics of Japan, 1899–1997 (CD-ROM, in Japanese) Tokyo, Japan: Health, Labour and Welfare Statistics Association.Google Scholar
Mott, JA, Wolfe, MI, Alverson, CJ, Macdonald, SC, Bailey, CR, Ball, LB, Moorman, JE, Somers, JH, Mannino, DM and Redd, SC (2002) National vehicle emissions policies and practices and declining US carbon monoxide–related mortality. JAMA 288, 988–995.Google Scholar
Nordentoft, M, Qin, P, Helweg-Larsen, K and Juel, K (2006) Time-trends in method-specific suicide rates compared with the availability of specific compounds. The Danish experience. Nordic Journal of Psychiatry 60, 97–106.Google Scholar
Ohberg, A and Lonnqvist, J (1998) Suicides hidden among undetermined deaths. Acta Psychiatrica Scandinavica 98, 214–218.Google Scholar
Routley, V (2007) Motor vehicle exhaust gas suicide: review of countermeasures. Crisis 28, 28–35.Google Scholar
Routley, V and Ozanne-Smith, J (1998) The impact of catalytic converters on motor vehicle exhaust gas suicides. Medical Journal of Australia 168, 65–67.Google Scholar
Skilling, GD, Sclare, PD, Watt, SJ and Fielding, S (2008) The effect of catalytic converter legislation on suicide rates in Grampian and Scotland 1980–2003. Scottish Medical Journal 53, 3–6.Google Scholar
Statistics Japan (2008) Population estimates in Japan, 1920–2000. Available at http://www.e-stat.go.jp/SG1/estat/List.do?bid=000000090004&cycode=0 (Accessed 13 Februry 2018).Google Scholar
Statistics Japan (2017) Labor Force Survey: Long Term Time-Series Data. Available at http://www.stat.go.jp/data/roudou/longtime/03roudou.html (Accessed 12 June 2018).Google Scholar
Thomas, K and Gunnell, D (2010) Suicide in England and Wales 1861–2007: a time-trends analysis. International Journal of Epidemiology 39, 1464–1475.Google Scholar
Thomas, K, Chang, SS and Gunnell, D (2011) Suicide epidemics: the impact of newly emerging methods on overall suicide rates – a time trends study. BMC Public Health 11, 314.Google Scholar
Thomsen, AH and Gregersen, M (2006) Suicide by carbon monoxide from car exhaust-gas in Denmark 1995–1999. Forensic Science International 161, 41–46.Google Scholar
Yamasaki, A, Araki, S, Sakai, R, Yokoyama, K and Voorhees, AS (2008) Suicide mortality of young, middle-aged and elderly males and females in Japan for the years 1953–96: time series analysis for the effects of unemployment, female labour force, young and aged population, primary industry and population density. Industrial Health 46, 541–549.Google Scholar
Yip, PS, Caine, E, Yousuf, S, Chang, SS, Wu, KC and Chen, YY (2012) Means restriction for suicide prevention. Lancet 379, 2393–2399.Google Scholar