|Last updated: January 2017
Suggested citation: Campbell MA, Ford C, & Winstanley MH. Ch 4. The health effects of secondhand smoke. 4.7 Estimates of morbidity and mortality attributable to secondhand smoke. In Scollo, MM and Winstanley, MH [editors]. Tobacco in Australia: Facts and issues. Melbourne: Cancer Council Victoria; 2017. Available from http://www.tobaccoinaustralia.org.au/chapter-4-secondhand/4-7-estimates-of-morbidity-and-mortality
In 2011 the World Health Organization estimated the global burden of disease from exposure to secondhand smoke using data from 2004.1 More than 600,000 premature deaths in 2004 were attributed to secondhand smoke exposure, and of these deaths 168,000 or 28% were estimated to be in children.
Estimates based on data from the US2 and the UK2, 3 show that for every 10 deaths caused by smoking among smokers, one death also occurs in a non-smoker due to exposure to secondhand smoke. Of all deaths in the US, secondhand smoke is thought to be responsible for as many as 2.7% each year.4 These deaths are thought to occur disproportionately among disadvantaged and minority groups.
There is very limited information from Australia regarding morbidity and mortality attributable to secondhand smoke. A small number of reports have published estimates of deaths caused by secondhand smoke, however these vary dramatically due to differences in methodology and diseases included in analysis. Findings from these studies are summarised below.
The Department of Health and Ageing estimated that 141 Australians died from secondhand smoke in 2004–05.5 Of these, 113 deaths occurred in adults and 28 deaths occurred in babies (Table 4.7.1).
Estimated numbers of deaths caused by secondhand smoke in Australia, 2004–2005 (Department of Health and Ageing, 2007)
* Deaths in infancy are based on exposure to active maternal smoking during pregnancy and/or following birth
Note: Columns may not add up to total due to rounding
Source: Unpublished data from research undertaken for Collins and Lapsley, 20085
About 90% of the deaths caused by secondhand smoke in adulthood were due to ischaemic heart disease. Most deaths caused by secondhand smoke occur later in life, reflecting the contribution of chronic lifelong exposure to the development of heart disease and lung cancer. There were more than twice as many deaths among adult women as there were among men reflecting the historically higher rates of non-smoking among women in previous decades.
These estimates are likely to be very conservative, since they do not include deaths from all of the diseases now understood to be associated with secondhand smoke exposure. Additionally, the estimates for deaths from lung cancer caused by secondhand smoke are restricted to exposed non-smokers married to a smoker and therefore exclude non-smokers exposed to secondhand smoke in workplaces and other settings). Finally, a cautious approach to quantifying deaths from ischaemic heart disease was adopted compared with the methods used in studies below.
While this report does not quantify morbidity (non-fatal illness) caused by secondhand smoke, the report states that ‘the overwhelming proportion of the morbidity attributable to involuntary smoking ... is borne by the young’.5 In a previous report, it was estimated that secondhand smoking caused close to 2000 hospital admissions in Australia in 1998. About three-quarters of these admissions were estimated to have occurred in children under the age of 14.6
In a study published by the Cancer Council NSW, US data was extrapolated to the Australian population to estimate the number of deaths attributable to secondhand smoke.7 This study estimated that in 1998 4200 adult non-smokers died in Australia from secondhand smoke. These estimates are based on deaths from a a wider range of diseases than those considered in the Department of Health and Ageing reports discussed above, but exclude deaths in infancy and childhood. The Cancer Council NSW report notes that even if only deaths from lung cancer and heart disease caused by secondhand smoke are considered the annual toll from secondhand smoke is still over 3400 deaths.7
Estimated numbers of deaths caused by secondhand smoke in Australia, 1998*
*Adults aged 15+
Source: Excerpt from Table 1 in Repace7
Estimates of mortality published by the National Health and Medical Research Council (NHMRC) in 1997 showed that 11 deaths from lung cancer and 77 deaths from a major cardiovascular event could be attributable to secondhand smoke annually.8 The authors acknowledged that these estimates are likely to be very conservative because they are restricted to never smokers who had been exposed to secondhand smoke in their home, due to limitations in the availability of more general Australian exposure data.
The NHMRC information paper also explored morbidity and estimated that secondhand smoke was a factor in causing asthma symptoms in 46,500 Australian children annually, and causing lower respiratory illness in 16,300 children. More than 5000 hospital separations in children every year were estimated to be attributable to secondhand smoke.8
1. Oberg M, Woodward A, Jaakkola JJ, Peruga A, and Pruss-Ustun A. Global estimate of the burden of disease from second-hand smoke. Geneva: WHO, 2010. Available from: http://apps.who.int/iris/bitstream/10665/44426/1/9789241564076_eng.pdf
2. Armour BS, Woollery T, Malarcher A, Pechacek TF, and Husten C. Annual smoking-attributable mortality, years of potential life lost, and productivity losses--united states, 1997-2001. Morbidity and Mortality Weekly Report, 2005; 54(25):625−8. Available from: http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5425a1.htm
3. Jamrozik K. Estimate of deaths attributable to passive smoking among uk adults: Database analysis. British Medical Journal, 2005; 330:812–6. Available from: http://www.bmj.com/cgi/content/abstract/bmj.38370.496632.8Fv3
4. Repace J. Exposure to secondhand smoke, in Exposure analysis. Ott W, Steinemann A, and Wallace L, Editors. Boca Raton, Florida: Taylor & Francis Group - CRC Press; 2007. p 201–31 Available from: http://tobaccosmoke.exposurescience.org/abcs-of-shs/references
5. Collins D and Lapsley H. The costs of tobacco, alcohol and illicit drug abuse to australian society in 2004–05. Canberra: Department of Health and Ageing, 2008. Available from: http://www.nationaldrugstrategy.gov.au/internet/drugstrategy/publishing.nsf/Content/mono64/$File/mono64.pdf
6. Ridolfo B and Stevenson C. Quantification of drug-caused mortality and morbidity in australia, 1998. Drug statistics series no. 7, AIHW cat. no. PHE-29.Canberra: Australian Institute of Health and Welfare, 2001. Available from: http://www.aihw.gov.au/publications/phe/qdcmma98/
7. Repace J. Estimated mortality from secondhand smoke among club, pub, tavern and bar workers in new south wales, australia. A report commissioned by the cancer council new south wales. Woolloomooloo, Australia: The Cancer Council New South Wales, 2004. Available from: http://www.cancercouncil.com.au/editorial.asp?pageid=1020