Trends in suicide methods in Switzerland from 1969 to 2018: an observational study
BACKGROUND: Suicide is a serious societal and health problem. We examined changes in rates of completed suicides in Switzerland between 1969–2018 with particular regard to different methods of suicide used in different subgroups of the resident population.
METHODS: We used data of the Swiss cause of death statistics and Poisson regression models to analyse annual incidence rates and calendar time trends of specific suicide methods used in population subgroups by sex (men vs women), age (10–29, 30–64, >64 years), and nationality (Swiss vs other citizenship).
RESULTS: There were 64,996 registered suicides between 1969 and 2018. Across these 5 decades, the overall suicide rate was higher in men than in women (incidence rate ratio [IRR] 2.62, 95% confidence interval [CI] 2.58–2.67), in Swiss citizens than in foreigners (IRR 2.02; 95% CI 1.97–2.07), and in older residents (>64 years) than in the age groups 30–64 years (IRR 1.35, 95% CI 1.32–1.37) and 10–29 years (IRR 2.37, 95% CI 2.32–2.43). After peaking in the 1980s, the overall suicide rate had declined in all of these population subgroups, with flattening trends over most recent years. The most common specific methods of suicide were hanging (accounting for 26.7% of all suicides) and firearms (23.6%). The rates of the specific suicide methods were usually higher in men, in Swiss citizens and in older residents, and they had typically declined over most recent decades in the population subgroups examined. However, some methods diverged from this general pattern, at least in some population subgroups. For instance, railway suicides most recently increased in younger and in male residents whereas suicides by gas and by drowning were only at a low level after rapid declines in the last millennium.
CONCLUSIONS: Restricting access to lethal means (e.g., detoxification of domestic gas), improvements in health care and media guidelines for responsible reporting of suicides are possible explanations for the generally declining suicide rates in Switzerland. Whereas some methods (e.g., poisoning by gases or drowning) had become rare, others continue to account for many suicides every year, at least in some population subgroups (e.g., firearms in older Swiss men or railway suicides in younger and in male residents). As different methods of suicide are chosen by different people or subgroups of the population, preventive efforts should include differentiated strategies and targeted measures to further reduce suicides in Switzerland and elsewhere.
- World Health Organization. Suicide. Geneva: World Health Organization; 2022; Available from: https://www.who.int/news-room/fact-sheets/detail/suicide
- Fazel S, Runeson B. Suicide. N Engl J Med. 2020 Jan;382(3):266–74. https://doi.org/10.1056/NEJMra1902944
- Mann JJ, Michel CA, Auerbach RP. Improving Suicide Prevention Through Evidence-Based Strategies: A Systematic Review. Am J Psychiatry. 2021 Jul;178(7):611–24. https://doi.org/10.1176/appi.ajp.2020.20060864
- Mann JJ. Neurobiology of suicidal behaviour. Nat Rev Neurosci. 2003 Oct;4(10):819–28. https://doi.org/10.1038/nrn1220
- National Center for Injury Prevention and Control. Suicide prevention: A public health issue. Atlanta: Centers for Disease Control and Prevention; 2021; Available from: https://www.cdc.gov/violenceprevention/pdf/asap_suicide_issue2-a.pdf
- World Health Organization. Preventing suicide: A global imperative. Geneva: World Health Organization; 2014.
- World Health Organization. Comprehensive mental health action plan 2013-2030. Geneva: World Health Organization; 2021.
- Hepp U, Ring M, Frei A, Rössler W, Schnyder U, Ajdacic-Gross V. Suicide trends diverge by method: swiss suicide rates 1969-2005. Eur Psychiatry. 2010 Apr;25(3):129–35. https://doi.org/10.1016/j.eurpsy.2009.05.005
- Federal Statistical Office. Specific causes of death. Neuchatel: Federal Statistical Office; 2021; Available from: https://www.bfs.admin.ch/bfs/de/home/statistiken/gesundheit/gesundheitszustand/sterblichkeit-todesursachen/spezifische.html
- Federal Statistical Office. Transport accidents. Neuchatel: Federal Statistical Office; 2021; Available from: https://www.bfs.admin.ch/bfs/en/home/statistics/mobility-transport/accidents-environmental-impact/transport-accidents.html
- Ajdacic-Gross V, Weiss MG, Ring M, Hepp U, Bopp M, Gutzwiller F, et al. Methods of suicide: international suicide patterns derived from the WHO mortality database. Bull World Health Organ. 2008 Sep;86(9):726–32. https://doi.org/10.2471/BLT.07.043489
- Värnik A, Kõlves K, Allik J, Arensman E, Aromaa E, van Audenhove C, et al. Gender issues in suicide rates, trends and methods among youths aged 15-24 in 15 European countries. J Affect Disord. 2009 Mar;113(3):216–26. https://doi.org/10.1016/j.jad.2008.06.004
- Värnik A, Kõlves K, van der Feltz-Cornelis CM, Marusic A, Oskarsson H, Palmer A, et al. Suicide methods in Europe: a gender-specific analysis of countries participating in the “European Alliance Against Depression”. J Epidemiol Community Health. 2008 Jun;62(6):545–51. https://doi.org/10.1136/jech.2007.065391
- Hepp U, Stulz N, Unger-Köppel J, Ajdacic-Gross V. Methods of suicide used by children and adolescents. Eur Child Adolesc Psychiatry. 2012 Feb;21(2):67–73. https://doi.org/10.1007/s00787-011-0232-y
- Dahlberg LL, Ikeda RM, Kresnow MJ. Guns in the home and risk of a violent death in the home: findings from a national study. Am J Epidemiol. 2004 Nov;160(10):929–36. https://doi.org/10.1093/aje/kwh309
- Daigle MS. Suicide prevention through means restriction: assessing the risk of substitution. A critical review and synthesis. Accid Anal Prev. 2005 Jul;37(4):625–32. https://doi.org/10.1016/j.aap.2005.03.004
- Gunnell D, Middleton N, Frankel S. Method availability and the prevention of suicide—a re-analysis of secular trends in England and Wales 1950-1975. Soc Psychiatry Psychiatr Epidemiol. 2000 Oct;35(10):437–43. https://doi.org/10.1007/s001270050261
- McClure GM. Changes in suicide in England and Wales, 1960-1997. Br J Psychiatry. 2000 Jan;176(1):64–7. https://doi.org/10.1192/bjp.176.1.64
- Zalsman G, Hawton K, Wasserman D, van Heeringen K, Arensman E, Sarchiapone M, et al. Suicide prevention strategies revisited: 10-year systematic review. Lancet Psychiatry. 2016 Jul;3(7):646–59. https://doi.org/10.1016/S2215-0366(16)30030-X
- Federal Statistical Office. Cause of death and stillbirth statistics (CoD). Neuchatel: Federal Statistical Office; 2016; Available from: https://www.bfs.admin.ch/bfs/en/home/statistics/health/surveys/ecod.assetdetail.7037.html
- World Health Organization. International statistical classification of diseases and related health problems. Tenth revision. Geneva: World Health Organization; 2004.
- World Health Organization. International statistical classification of diseases and related health problems. Eighth revision. Geneva: World Health Organization; 1965.
- Federal Statistical Office. Demographic balance by age. Neuchatel: Federal Statistical Office; 2021; Available from: https://www.pxweb.bfs.admin.ch/pxweb/en/px-x-0102020000_103/-/px-x-0102020000_103.px/
- Kirkwood BR, Sterne AC. Essential medical statistics. Malden, MA: Blackwell; 2005. Chapter 24: Poisson regression; p. 249-262.
- StataCorp. Stata Statistical Software: Release 16. College Station (TX): StataCorp LLC; 2019.
- StataCorp. mkspline – linear and restricted cubic spline construction. In: StataCorp, editor. Stata 17 Base Reference Manual. College Station, TX: Stata Pres; 2019. p. 1551-7.
- Harrell FE. Regression Modeling Strategies. Cham: Springer; 2015. https://doi.org/10.1007/978-3-319-19425-7
- Croxford R. Restricted cubic spline regression: a brief introduction. Paper 5621-2016. Cary (NC): SAS Institute Inc; 2016.
- Stone CJ, Koo CY. Additive splines in statistics. In: American Statistical Association, editor. Proceedings of the Statistical Computing Section. Washington, DC: American Statistical Association; 1985. p. 45-8.
- Stone CJ. Generalized additive models. Stat Sci. 1986;1(3):312–4. https://doi.org/10.1214/ss/1177013607
- Federal Office of Public Health. Suicide prevention in Switzerland. Bern: Swiss Confederation; 2018.
- World Health Organization. Suicide in the world. Global health estimates. Geneva: World Health Organization; 2019.
- World Health Organization. Suicide and intentional self-harm, per 100 000 population. Copenhagen: World Health Organization; 2022. Available from: https://gateway.euro.who.int/en/indicators/hfamdb_771-sdr-suicide-and-intentional-self-harm-per-100-000/
- Alicandro G, Malvezzi M, Gallus S, La Vecchia C, Negri E, Bertuccio P. Worldwide trends in suicide mortality from 1990 to 2015 with a focus on the global recession time frame. Int J Public Health. 2019 Jun;64(5):785–95. https://doi.org/10.1007/s00038-019-01219-y
- Nordt C, Warnke I, Seifritz E, Kawohl W. Modelling suicide and unemployment: a longitudinal analysis covering 63 countries, 2000-11. Lancet Psychiatry. 2015 Mar;2(3):239–45. https://doi.org/10.1016/S2215-0366(14)00118-7
- Arsenault-Lapierre G, Kim C, Turecki G. Psychiatric diagnoses in 3275 suicides: a meta-analysis. BMC Psychiatry. 2004 Nov;4(1):37. https://doi.org/10.1186/1471-244X-4-37
- Schuler D, Tuch A, Peter C. Psychische Gesundheit in der Schweiz. Monitoring 2020. (Obsan Bericht 15/2020). Neuchâtel: Schweizerisches Gesundheitsobservatorium; 2020.
- Rutz W. Preventing suicide and premature death by education and treatment. J Affect Disord. 2001 Jan;62(1-2):123–9. https://doi.org/10.1016/S0165-0327(00)00356-6
- Szanto K, Kalmar S, Hendin H, Rihmer Z, Mann JJ. A suicide prevention program in a region with a very high suicide rate. Arch Gen Psychiatry. 2007 Aug;64(8):914–20. https://doi.org/10.1001/archpsyc.64.8.914
- Hegerl U, Maxwell M, Harris F, Koburger N, Mergl R, Székely A, et al.; OSPI-Europe Consortium. Prevention of suicidal behaviour: results of a controlled community-based intervention study in four European countries. PLoS One. 2019 Nov;14(11):e0224602. https://doi.org/10.1371/journal.pone.0224602
- Michel K, Valach L. Suicide prevention: spreading the gospel to general practitioners. Br J Psychiatry. 1992 Jun;160(6):757–60. https://doi.org/10.1192/bjp.160.6.757
- Chung D, Hadzi-Pavlovic D, Wang M, Swaraj S, Olfson M, Large M. Meta-analysis of suicide rates in the first week and the first month after psychiatric hospitalisation. BMJ Open. 2019 Mar;9(3):e023883. https://doi.org/10.1136/bmjopen-2018-023883
- Chung DT, Ryan CJ, Hadzi-Pavlovic D, Singh SP, Stanton C, Large MM. Suicide Rates After Discharge From Psychiatric Facilities: A Systematic Review and Meta-analysis. JAMA Psychiatry. 2017 Jul;74(7):694–702. https://doi.org/10.1001/jamapsychiatry.2017.1044
- Gibbons RD, Brown CH, Hur K, Marcus SM, Bhaumik DK, Mann JJ. Relationship between antidepressants and suicide attempts: an analysis of the Veterans Health Administration data sets. Am J Psychiatry. 2007 Jul;164(7):1044–9. https://doi.org/10.1176/ajp.2007.164.7.1044
- Simon GE, Savarino J, Operskalski B, Wang PS. Suicide risk during antidepressant treatment. Am J Psychiatry. 2006 Jan;163(1):41–7. https://doi.org/10.1176/appi.ajp.163.1.41
- Ludwig J, Marcotte DE. Anti-depressants, suicide, and drug regulation. J Policy Anal Manage. 2005 Mar;24(2):249–72. https://doi.org/10.1002/pam.20089
- Ludwig J, Marcotte DE, Norberg K. Anti-depressants and suicide. J Health Econ. 2009 May;28(3):659–76. https://doi.org/10.1016/j.jhealeco.2009.02.002
- Rihmer Z. Can better recognition and treatment of depression reduce suicide rates? A brief review. Eur Psychiatry. 2001 Nov;16(7):406–9. https://doi.org/10.1016/S0924-9338(01)00598-3
- Pettrone K, Curtin SC. Urban-rural differences in suicide rates, by sex and three leading methods: united States, 2000-2018. NCHS Data Brief. 2020 Aug;(373):1–8.
- Pratt LA, Brody DJ, Gu Q. Antidepressant Use Among Persons Aged 12 and Over:United States,2011-2014. NCHS Data Brief. 2017 Aug;(283):1–8.
- Ajdacic-Gross V, Hepp U, Seifritz E, Bopp M. Rethinking suicides as mental accidents: towards a new paradigm. J Affect Disord. 2019 Jun;252:141–51. https://doi.org/10.1016/j.jad.2019.04.022
- Stulz N, Hepp U, Gosoniu DG, Grize L, Muheim F, Weiss MG, et al. Patient-identified priorities leading to attempted suicide. Crisis. 2018 Jan;39(1):37–46. https://doi.org/10.1027/0227-5910/a000473
- Yip PS, Caine E, Yousuf S, Chang SS, Wu KC, Chen YY. Means restriction for suicide prevention. Lancet. 2012 Jun;379(9834):2393–9. https://doi.org/10.1016/S0140-6736(12)60521-2
- Turvill JL, Burroughs AK, Moore KP. Change in occurrence of paracetamol overdose in UK after introduction of blister packs. Lancet. 2000;355(9220):2048–9. https://doi.org/10.1016/S0140-6736(00)02355-2
- Hawton K, Bergen H, Simkin S, Dodd S, Pocock P, Bernal W, et al. Long term effect of reduced pack sizes of paracetamol on poisoning deaths and liver transplant activity in England and Wales: interrupted time series analyses. BMJ. 2013 Feb;346 feb07 1:f403. https://doi.org/10.1136/bmj.f403
- Steck N, Egger M, Zwahlen M; Swiss National Cohort. Assisted and unassisted suicide in men and women: longitudinal study of the Swiss population. Br J Psychiatry. 2016 May;208(5):484–90. https://doi.org/10.1192/bjp.bp.114.160416
- Federal Statistical Office. Anteil der ständigen ausländischen Wohnbevölkerung. Neuchatel: Federal Statistical Office; 2021. Available from: https://www.bfs.admin.ch/bfs/en/home/statistics/population/migration-integration/foreign.assetdetail.18264545.html
- Lester D. The effect of the detoxification of domestic gas in Switzerland on the suicide rate. Acta Psychiatr Scand. 1990 Nov;82(5):383–4. https://doi.org/10.1111/j.1600-0447.1990.tb01406.x
- Amos T, Appleby L, Kiernan K. Changes in rates of suicide by car exhaust asphyxiation in England and Wales. Psychol Med. 2001 Jul;31(5):935–9. https://doi.org/10.1017/S0033291701003920
- Nordentoft M, Qin P, Helweg-Larsen K, Juel K. Restrictions in means for suicide: an effective tool in preventing suicide: the Danish experience. Suicide Life Threat Behav. 2007 Dec;37(6):688–97. https://doi.org/10.1521/suli.2007.37.6.688
- Studdert DM, Gurrin LC, Jatkar U, Pirkis J. Relationship between vehicle emissions laws and incidence of suicide by motor vehicle exhaust gas in Australia, 2001-06: an ecological analysis. PLoS Med. 2010 Jan;7(1):e1000210. https://doi.org/10.1371/journal.pmed.1000210
- Thomas K, Chang SS, Gunnell D. Suicide epidemics: the impact of newly emerging methods on overall suicide rates - a time trends study. BMC Public Health. 2011 May;11(1):314. https://doi.org/10.1186/1471-2458-11-314
- Gunnell D, Bennewith O, Hawton K, Simkin S, Kapur N. The epidemiology and prevention of suicide by hanging: a systematic review. Int J Epidemiol. 2005 Apr;34(2):433–42. https://doi.org/10.1093/ije/dyh398
- Large M, Nielssen O. The need to prevent suicide by hanging in Australia. Aust N Z J Psychiatry. 2021 May;55(5):519–20. https://doi.org/10.1177/0004867420951249
- Kapur N, Hunt IM, Windfuhr K, Rodway C, Webb R, Rahman MS, et al. Psychiatric in-patient care and suicide in England, 1997 to 2008: a longitudinal study. Psychol Med. 2013 Jan;43(1):61–71. https://doi.org/10.1017/S0033291712000864
- Shenassa ED, Catlin SN, Buka SL. Lethality of firearms relative to other suicide methods: a population based study. J Epidemiol Community Health. 2003 Feb;57(2):120–4. https://doi.org/10.1136/jech.57.2.120
- de Moore GM, Robertson AR. Suicide attempts by firearms and by leaping from heights: a comparative study of survivors. Am J Psychiatry. 1999 Sep;156(9):1425–31. https://doi.org/10.1176/ajp.156.9.1425
- Ajdacic-Gross V, Killias M, Hepp U, Gadola E, Bopp M, Lauber C, et al. Changing times: a longitudinal analysis of international firearm suicide data. Am J Public Health. 2006 Oct;96(10):1752–5. https://doi.org/10.2105/AJPH.2005.075812
- Ajdacic-Gross V, Killias M, Hepp U, Haymoz S, Bopp M, Gutzwiller F, et al. Firearm suicides and availability of firearms: the Swiss experience. Eur Psychiatry. 2010 Nov;25(7):432–4. https://doi.org/10.1016/j.eurpsy.2010.04.006
- Thoeni N, Reisch T, Hemmer A, Bartsch C. Suicide by firearm in Switzerland: who uses the army weapon? Results from the national survey between 2000 and 2010. Swiss Med Wkly. 2018 Sep;148:w14646. https://doi.org/10.4414/smw.2018.14646
- Reisch T, Steffen T, Habenstein A, Tschacher W. Change in suicide rates in Switzerland before and after firearm restriction resulting from the 2003 “Army XXI” reform. Am J Psychiatry. 2013 Sep;170(9):977–84. https://doi.org/10.1176/appi.ajp.2013.12091256
- Farmer R, Rohde J. Effect of availability and acceptability of lethal instruments on suicide mortality. An analysis of some international data. Acta Psychiatr Scand. 1980 Nov;62(5):436–46. https://doi.org/10.1111/j.1600-0447.1980.tb00632.x
- Gunnell D, Nowers M. Suicide by jumping. Acta Psychiatr Scand. 1997 Jul;96(1):1–6. https://doi.org/10.1111/j.1600-0447.1997.tb09897.x
- Mohl A, Stulz N, Martin A, Eigenmann F, Hepp U, Hüsler J, et al. The “Suicide Guard Rail”: a minimal structural intervention in hospitals reduces suicide jumps. BMC Res Notes. 2012 Aug;5(1):408. https://doi.org/10.1186/1756-0500-5-408
- Beautrais A. Suicide by Jumping. Crisis. 2007 Jan;28(S1 Suppl 1):58–63. https://doi.org/10.1027/0227-5910.28.S1.58
- Reisch T, Michel K. Securing a suicide hot spot: effects of a safety net at the Bern Muenster Terrace. Suicide Life Threat Behav. 2005 Aug;35(4):460–7. https://doi.org/10.1521/suli.2005.35.4.460
- Reisch T, Schuster U, Michel K. Suicide by jumping and accessibility of bridges: results from a national survey in Switzerland. Suicide Life Threat Behav. 2007 Dec;37(6):681–7. https://doi.org/10.1521/suli.2007.37.6.681
- Hemmer A, Meier P, Reisch T. Comparing Different Suicide Prevention Measures at Bridges and Buildings: Lessons We Have Learned from a National Survey in Switzerland. PLoS One. 2017 Jan;12(1):e0169625. https://doi.org/10.1371/journal.pone.0169625
- Pirkis J, Spittal MJ, Cox G, Robinson J, Cheung YT, Studdert D. The effectiveness of structural interventions at suicide hotspots: a meta-analysis. Int J Epidemiol. 2013 Apr;42(2):541–8. https://doi.org/10.1093/ije/dyt021
- Sinyor M, Levitt AJ. Effect of a barrier at Bloor Street Viaduct on suicide rates in Toronto: natural experiment. BMJ. 2010 Jul;341 jul06 1:c2884. https://doi.org/10.1136/bmj.c2884
- Steck N, Egger M, Schimmelmann BG, Kupferschmid S; Swiss National Cohort. Suicide in adolescents: findings from the Swiss National cohort. Eur Child Adolesc Psychiatry. 2018 Jan;27(1):47–56. https://doi.org/10.1007/s00787-017-1019-6
- Wyss Schneider T, Teotino G, Hepp U. Schienensuizide auf dem Netz der SBB. Dossier zu Präventionsmassnahmen, Handlungsbedarf und Empfehlungen. 2018. Available from https://news.sbb.ch/_file/10354/schienensuizide-auf-dem-netz-der-sbb.pdf
- Niederkrotenthaler T, Sonneck G. Assessing the impact of media guidelines for reporting on suicides in Austria: interrupted time series analysis. Aust N Z J Psychiatry. 2007 May;41(5):419–28. https://doi.org/10.1080/00048670701266680
- Barker E, Kolves K, De Leo D. Rail-suicide prevention: systematic literature review of evidence-based activities. Asia-Pac Psychiatry. 2017 Sep;9(3):e12246. https://doi.org/10.1111/appy.12246
- Sinyor M, Schaffer A, Nishikawa Y, Redelmeier DA, Niederkrotenthaler T, Sareen J, et al. The association between suicide deaths and putatively harmful and protective factors in media reports. CMAJ. 2018 Jul;190(30):E900–7. https://doi.org/10.1503/cmaj.170698
- Cox GR, Owens C, Robinson J, Nicholas A, Lockley A, Williamson M, et al. Interventions to reduce suicides at suicide hotspots: a systematic review. BMC Public Health. 2013 Mar;13(1):214. https://doi.org/10.1186/1471-2458-13-214
- Law CK, Yip PS, Chan WS, Fu KW, Wong PW, Law YW. Evaluating the effectiveness of barrier installation for preventing railway suicides in Hong Kong. J Affect Disord. 2009 Apr;114(1-3):254–62. https://doi.org/10.1016/j.jad.2008.07.021
- Turecki G, Brent DA. Suicide and suicidal behaviour. Lancet. 2016 Mar;387(10024):1227–39. https://doi.org/10.1016/S0140-6736(15)00234-2
- Runeson B, Tidemalm D, Dahlin M, Lichtenstein P, Långström N. Method of attempted suicide as predictor of subsequent successful suicide: national long term cohort study. BMJ. 2010 Jul;341 jul13 1:c3222. https://doi.org/10.1136/bmj.c3222
- Miller M, Hemenway D. Guns and suicide in the United States. N Engl J Med. 2008 Sep;359(10):989–91. https://doi.org/10.1056/NEJMp0805923
- Simon OR, Swann AC, Powell KE, Potter LB, Kresnow MJ, O’Carroll PW. Characteristics of impulsive suicide attempts and attempters. Suicide Life Threat Behav. 2001;32(1 Suppl):49–59.