Relationship between Vehicle Emissions Laws and Incidence of Suicide by Motor Vehicle Exhaust Gas in Australia, 2001–06: An Ecological Analysis

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Background:
Globally, suicide accounts for 5.2% of deaths among persons aged 15 to 44 years and its incidence is rising. In Australia, suicide rates peaked in 1997 and have been declining since. A substantial part of that decline stems from a plunge in suicides by one particular method: asphyxiation by motor vehicle exhaust gas (MVEG). Although MVEG remains the second most common method of suicide in Australia, its incidence decreased by nearly 70% in the decade to 2006. The extent to which this phenomenon has been driven by national laws in 1986 and 1999 that lowered permissible levels of carbon monoxide (CO) emissions is unknown. The objective of this ecological study was to test the relationship by investigating whether areas of Australia with fewer noxious vehicles per capita experienced lower rates of MVEG suicide.

Methods and Findings:
We merged data on MVEG suicides in Australia (2001–06) with data on the number and age of vehicles in the national fleet, as well as socio-demographic data from the national census. Poisson regression was used to analyse the relationship between the incidence of suicide within two levels of geographical area—postcodes and statistical subdivisions (SSDs)—and the population density of pre-1986 and pre-1999 passenger vehicles in those areas. (There was a mean population of 8,302 persons per postcode in the study dataset and 87,413 persons per SSD.) The annual incidence of MVEG suicides nationwide decreased by 57% (from 2.6 per 100,000 in 2001 to 1.1 in 2006) during the study period; the population density of pre-1986 and pre-1999 vehicles decreased by 55% (from 14.2 per 100 persons in 2001 to 6.4 in 2006) and 26% (from 44.5 per 100 persons in 2001 to 32.9 in 2006), respectively. Area-level regression analysis showed that the suicide rates were significantly and positively correlated with the presence of older vehicles. A percentage point decrease in the population density of pre-1986 vehicles was associated with a 6% decrease (rate ratio [RR] = 1.06; 95% confidence interval [CI] 1.05–1.08) in the incidence of MVEG suicide within postcode areas; a percentage point decrease in the population density of pre-1999 vehicles was associated with a 3% decrease (RR = 1.03; 95% CI 1.02–1.04) in the incidence of MVEG suicide.

Conclusions:
Areas of Australia with fewer vehicles predating stringent CO emission laws experience lower rates of MVEG suicide. Although those emission laws were introduced primarily for environmental reasons, countries that lack them may miss the benefits of a serendipitous suicide prevention strategy.

: Please see later in the article for the Editors' Summary

Vyšlo v časopise: Relationship between Vehicle Emissions Laws and Incidence of Suicide by Motor Vehicle Exhaust Gas in Australia, 2001–06: An Ecological Analysis. PLoS Med 7(1): e32767. doi:10.1371/journal.pmed.1000210
Kategorie: Research Article
prolekare.web.journal.doi_sk: https://doi.org/10.1371/journal.pmed.1000210

Souhrn

Zdroje

1. World Health Organization 2008 The global burden of disease: 2004 update Geneva World Health Organization Available: http://www.who.int/healthinfo/global_burden_disease/2004_report_update/en/index.html. Accessed 1 June 2009

2. Australian Bureau of Statistics 2006 Causes of death. Catalogue No. 3303.0 Commonwealth of Australia Canberra Australian Bureau of Statistics

3. Motor Vehicles Standards Act 1989 (Cwlth) 1984 Australian Design Rule 37/00: emission control for light vehicles Canberra Department of Transportation and Regional Services

4. Motor Vehicles Standards Act 1989 (Cwlth) 1985 Australian Design Rule 37/01: emission control for light vehicles Canberra Department of Transport and Regional Services

5. RoutleyVH

Ozanne-SmithJ

1998 The impact of catalytic converters on motor vehicle exhaust gas suicides. Med J Aust 168 65 67

6. BrennanC

RoutleyV

Ozanne-SmithJ

2006 Motor vehicle gas suicide in Victoria, Australia 1998–2002. Crisis 27 119 124

7. MottJA

WolfeMI

AlversonCJ

MacdonaldSC

BaileyCR

2002 National vehicle emissions policies and practices and declining US carbon monoxide-related mortality. JAMA 288 988 995

8. KendellRE

1998 Catalytic converters and prevention of suicides. Lancet 352 1525

9. AmosT

ApplebyL

KiernanK

2001 Changes in rates of suicide by car exhaust asphyxiation in England and Wales. Psychol Med 31 935 939

10. McClureGM

2000 Changes in suicide in England and Wales. Brit J Psych 176 64 67

11. Victorian Institute of Forensic Medicine 2007 NCIS Annual Report, 2006–07. Available: http://www.vifp.monash.edu.au/ncis/NCIS_ANNUAL_REPORT-06-07.pdf. Accessed 1 June 2009

12. Victorian Institute of Forensic Medicine 2007 National Coroners Information System coding manual and user guide. Version 3. August 2007 Melbourne Victorian Institute of Forensic Medicine

13. National Coroners Information System. Quality review activities and quality assurance audits. Available: http://www.ncis.org.au/web_pages/quality_reviews.htm. Accessed 8 December 2009

14. DakingL

DoddsL

2007 ICD-10 mortality coding and the NCIS: a comparative study. Health Inf Man J 36 11 23

15. DriscollTR

HenleyG

HarrisonJE

2003 The National Coroners Information System as an information tool for injury surveillance. Catalogue no. INJCAT 60 Canberra Australian Institute of Health and Welfare

16. De LeoD

2006 Suicide mortality data need revision. Med J Aust 186 157 158

17. WalkerS

ChenL

MaddenR

2008 Deaths due to suicide: the effects of certification and coding practices in Australia. Aust New Zeal J Pub Health 32 126 130

18. Australian Bureau of Statistics 2008 Motor vehicle census. ABS Catalogue No. 9309.0 Commonwealth of Australia Canberra Australian Bureau of Statistics

19. Australian Bureau of Statistics 2006 How Australia takes a census. ABS Catalogue No. 2903.0. Commonwealth of Australia Canberra Australian Bureau of Statistics

20. National Academy, Institute of Medicine 2002 Reducing suicide: a national imperative Washington (D.C) National Academy, Institute of Medicine

21. HawtonK

van HeeringenK

2000 The international handbook of suicide and attempted suicide West Sussex John Wiley & Sons

22. Australian Bureau of Statistics 2008 Australian Geographical Classification System. ABS Catalogue No. 1216.0. Commonwealth of Australia Canberra Australian Bureau of Statistics

23. FaizA

WeaverCS

WalshMP

1996 Air pollution from motor vehicles: standards and technologies for controlling emissions Washington (D.C.) World Bank

24. BiddleL

BrockA

BrookesST

GunnellD

2008 Suicide rates in young men in England and Wales in the 21st century: time trend study. Brit Med J 336 539 542

25. NordentoftM

PingQ

Helweg-LarsenK

2007 Restrictions in means for suicide: an effective tool in preventing suicide: the Danish experience. Suicide Life Threat Behav 36 688 697

26. ThomsenAH

GeregersenM

2006 Suicide by carbon monoxide from car exhaust-gas in Denmark 1995–1999. Forensic Sci Int 161 41 46

27. RoutleyV

2007 Motor vehicle exhaust gas suicide: review of countermeasures. Crisis 28 28 35

28. ClarkeRVG

LesterD

1989 Suicide: Closing the exits New York Springer Verlag

29. MannJJ

ApterA

BertoloteJ

BeautraisA

CurrierD

2005 Suicide prevention strategies: a systematic review. JAMA 294 2064 2074

30. KreitmanN

1976 The coal gas story. United Kingdom suicide rates, 1960–71. Brit J Prev Soc Med 30 86 93

31. GunnellD

MiddeltonN

FrankelS

2000 Method availability and the prevention of a suicide: a re-analysis of secular trends in England and Wales 1950–1975. Soc Psychiatry Psychiatr Epidemiol 25 437 443

32. LesterD

AbeK

1989 The effect of restricting access to lethal methods for suicide: A study of suicide by domestic gas in Japan. Acta Psych Scand 80 180 182

33. TurvillJL

BurroughsAK

MooreKP

2000 Change in occurrence of paracetamol overdose in UK after introduction of blister packs. Lancet 355 2048 2049

34. HawtonK

TownsendE

DeeksJ

ApplebyL

GunnellD

2001 Effects of legislation restricting pack sizes of paracetamol and salicylate on self poisoning in the United Kingdom: before and after study. Brit Med J 322 1 7

35. GunnellD

HawtonK

MurrayV

GarnierR

BismuthC

1997 Use of paracetamol for suicide and non-fatal poisoning in the UK and France: Are restrictions on availability justified? J Epid Comm Health 51 175 179

36. WakemanJ

2008 Ecologic studies revisited. Ann Rev Public Health 29 75 90

37. PirkisJ

BeautraisA

DurkeeT

2009 Suicide attempts in New Zealand and Australia.

WassermanD

WassermanC

The Oxford textbook of suicidology: a global perspective Oxford Oxford University Press

38. CONCAWE 2006 Motor vehicle emission regulations and fuel specifications - Part 1 2004/2005 update. Report No 05/06 Brussels CONCAWE

39. Asian Development Bank 2003 Reducing vehicle emissions in Asia, 2003. Available: http://www.adb.org/documents/guidelines/Vehicle_Emissions/reducing_vehicle_emissions.pdf. Accessed 1 June 2009

40. McGranahanG

MurrayF

2003 Air pollution and health in rapidly developing countries London Earthscan Publishers

41. National Research Council 1996 Meeting the challenges of megacities in the developing world Washington (D.C.) National Academy Press