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Neuropsychobiology 2008;57:32–37

Seasonality and Climatic Associations with Violent and Nonviolent Suicide: A Population-Based Study

Lin H.-C.a · Chen C.-S.c · Xirasagar S.e · Lee H.-C.b, d
aSchool of Health Care Administration and bDepartment of Psychiatry, School of Medicine, Taipei Medical University, cDepartment of Economics, National Taipei University, and dDepartment of Psychiatry, Taipei Medical University Hospital, Taipei, Taiwan; eArnold School of Public Health, University of South Carolina, Columbia, S.C., USA
email Corresponding Author

 goto top of outline Key Words

  • Violent suicide
  • Nonviolent suicide
  • Seasonality

 goto top of outline Abstract

Background: Using 7-year population-based data on Taiwan, we examined seasonal variation in violent versus nonviolent suicide, and its association with meteorological factors: ambient temperature, relative humidity, atmospheric pressure, rainfall and daily sunshine hours. Methods: We used Taiwan’s nationwide mortality data from 1997 to 2003, categorizing the sample decedents into two groups, violent (ICD-9-CM codes E953–E958) and nonviolent (E950–E952) suicide, based on the suicide method used. Seasonal autoregressive integrated moving average (SARIMA) modeling was used to detect seasonality of suicide, and the association of climate variables with violent versus nonviolent suicide. Results: The SARIMA test of seasonality was significant for both genders and the pooled sample (all p < 0.001) in violent suicide deaths, but not nonviolent suicides. Seasonal trends show a significant peak in March–May (early to late spring) for violent suicides. Increasing ambient temperature predicted increasing violent suicide rates. Conclusions: We conclude that seasonality exists in violent but not nonviolent suicide rates. Our findings suggest that suicide is a heterogeneous phenomenon and violent suicide may be more influenced by biochemical and chronobiological mechanisms.

Copyright © 2008 S. Karger AG, Basel

 goto top of outline References
  1. World Health Organization: Suicide prevention. 2005. http://www.who.int/mental_health/prevention/suicide/suicideprevent/en/.
  2. Qin P: Suicide risk in relation to level of urbanicity – a population-based linkage study. Int J Epidemiol 2005;34:846–852.
  3. Qin P, Agerbo E, Mortensen PB: Suicide risk in relation to socioeconomic, demographic, psychiatric, and familial factors: a national register-based study of all suicides in Denmark, 1981–1997. Am J Psychiatry 2003;160:765–772.
  4. Begley M, Quayle E: The lived experience of adults bereaved by suicide: a phenomenological study. Crisis 2007;28:26–34.

    External Resources

  5. Lorant V, Kunst AE, Huisman M, Bopp M, Mackenbach J, the EU Working Group: A European comparative study of marital status and socio-economic inequalities in suicide. Soc Sci Med 2005;60:2431–2441.
  6. Lee HC, Lin HC, Tsai SY, Li CY, Chen CC, Huang CC: Suicide rates and the association with climate: a population-based study. J Affect Disord 2006;92:221–226.
  7. Kung HC, Pearson JL, Liu XH: Risk factors for male and female suicide decedents aged 15–64 in the United States – results from the 1993 National Mortality Followback Survey. Soc Psychiatry Psychiatr Epidemiol 2003;38:419–426.
  8. Agerbo E, Qin P, Mortensen PB: Psychiatric illness, socioeconomic status, and marital status in people committing suicide: a matched case-sibling-control study. J Epidemiol Community Health 2006;60:776–781.
  9. Smith JC, Mercy JA, Conn JM: Marital status and the risk of suicide. Am J Public Health 1988;178:78–80.

    External Resources

  10. Lester D: Seasonal variation in suicidal deaths. Br J Psychiatry 1971;118:627–628.
  11. Marcinko D, Martinac M, Karlovic D, Filipcic I, Loncar C, Pivac N, Jakovljevic M: Are there differences in serum cholesterol and cortisol concentrations between violent and non-violent schizophrenic male suicide attempters? Coll Antropol 2005;29:153–157.
  12. Lester D: Seasonal variation in suicidal deaths by each method. Psychol Rep 1985;56:650.
  13. Lahti A, Räsänen P, Karvonen K, Särkioja T, Meyer-Rochow VB, Hakko H: Autumn peak in shooting suicides of children and adolescents from northern Finland. Neuropsychobiology 2006;54:140–146.
  14. Kalediene R, Starkuviene S, Petrauskiene J: Seasonal patterns of suicides over the period of socio-economic transition in Lithuania. BMC Public Health 2006;6:40.
  15. Maes M, Cosyns P, Meltzer HY, De Meyer F, Peeters D: Seasonality in violent suicide but not in nonviolent suicide or homicide. Am J Psychiatry 1993;150:1380–1385.
  16. Hakko H, Räsänen P, Tiihonen J: Secular trends in the rates and seasonality of violent and nonviolent suicide occurrences in Finland during 1980–95. J Affect Disord 1998;50:49–54.
  17. Räsänen P, Hakko H, Jokelainen J, Tiihonen J: Seasonal variation in specific methods of suicide: a national register study of 20,234 Finnish people. J Affect Disord 2002;71:51–59.
  18. Ajdacic-Gross V, Wang J, Bopp M, Eich D, Rossler W, Gutzwiller F: Are seasonalities in suicide dependent on suicide methods? A reappraisal. Soc Sci Med 2003;57:1173–1181.
  19. Alvarez JC, Cremniter D, Gluck N, Quintin P, Leboyer M, Berlin I, Therond P, Spreux-Varoquaux O: Low serum cholesterol in violent but not in non-violent suicide attempters. Psychiatry Res 2000;95:103–108.
  20. Box GEP, Jenkins GM: Time Series Analysis Forecasting and Control, ed 3. San Francisco, Holden-Day, 1994.
  21. Preti A, Miotto P: Seasonality in suicides: the influence of suicide method, gender and age on suicide distribution in Italy. Psychiatry Res 1998;81:219–231.
  22. Simkin S, Hawton K, Yip PS, Yam CH: Seasonality in suicide: a study of farming suicides in England and Wales. Crisis 2003;24:93–97.
  23. Parker G, Gao F, Machin D: Seasonality of suicide in Singapore: data from the equator. Psychol Med 2001;31:549–553.
  24. Spreux-Varoquaux O, Alvarez JC, Berlin I, Batista G, Despierre PG, Gilton A, Cremniter D: Differential abnormalities in plasma 5-HIAA and platelet serotonin concentrations in violent suicide attempters: relationships with impulsivity and depression. Life Sci 2001;69:647–657.
  25. Traskman-Bendz L, Alling C, Oreland L, Regnell G, Vinge E, Ohman R: Prediction of suicidal behavior from biologic tests. J Clin Psychopharmacol 1992;12:21S–26S.
  26. Mann JJ, Marzuk PM, Arango V, McBride PA, Leon AC, Tierney H: Neurochemical studies of violent and nonviolent suicide (review). Psychopharmacol Bull 1989;25:407–413.
  27. Yip PS, Chao A, Chiu CW: Seasonal variation in suicides: diminished or vanished. Experience from England and Wales, 1982–1996. Br J Psychiatry 2000;177:366–369.
  28. Preti A, Miotto P: Influence of method on seasonal distribution of attempted suicides in Italy. Neuropsychobiology 2000;41:62–72.
  29. Maes M, De Meyer F, Thompson P, Peeters D, Cosyns P: Synchronized annual rhythms in violent suicide rate, ambient temperature and the light-dark span. Acta Psychiatr Scand 1994;90:391–396.
  30. Villeneuve PJ, Leech J, Bourque D: Frequency of emergency room visits for childhood asthma in Ottawa, Canada: the role of weather. Int J Biometeorol 2005;50:48–56.
  31. Reichert TA, Simonsen L, Sharma A, Pardo SA, Fedson DS, Miller MA: Influenza and the winter increase in mortality in the United States, 1959–1999. Am J Epidemiol 2004;160:492–502.
  32. Lam LT: The association between climatic factors and childhood illnesses presented to hospital emergency among young children. Int J Environ Health Res 2007;17:1–8.

 goto top of outline Author Contacts

Herng-Ching Lin
School of Health Care Administration, Taipei Medical University
250 Wu-Hsing Street
Taipei 110 (Taiwan)
Tel. +886 2 2736 1661, ext. 3613, Fax +886 2 2378 9788, E-Mail henry11111@tmu.edu.tw

 goto top of outline Article Information

Received: June 11, 2007
Accepted after revision: January 22, 2008
Published online: May 2, 2008
Number of Print Pages : 6
Number of Figures : 1, Number of Tables : 2, Number of References : 32

 goto top of outline Publication Details

Neuropsychobiology (International Journal of Experimental and Clinical Research in Biological Psychiatry, Pharmacopsychiatry, Biological Psychology/Pharmacopsychology and Pharmacoelectroencephalography)

Vol. 57, No. 1-2, Year 2008 (Cover Date: June 2008)

Journal Editor: Strik W. (Bern)
ISSN: 0302–282X (Print), eISSN: 1423–0224 (Online)

For additional information: http://www.karger.com/NPS

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