Research from the US predicts that if smoking and solid fuel use in homes continues in China they will cause a total of 83 million deaths between 2003 and 2033 and that only large-scale interventions stand a chance of reducing this number.
The research is the work of a team from Harvard School of Public Health (HSPH) in Boston, Massachusetts, and is published online on October 4th and in the October 25th print issue of The Lancet. The quantitative study is the first to analyse the combined effects of smoking and use of household fuel on COPD, lung cancer and tuberculosis (TB).
The paper concludes that if the Chinese population continues to smoke and use biomass and coal fuel at current levels, between 2003 and 2033 an estimated 65 million of their people will die from COPD (chronic obstructive pulmonary disease) and another 18 million will die from lung cancer. These two causes will account for 80 per cent of COPD deaths and 75 per cent of lung cancer deaths, and will represent a total of 24 per cent of total deaths in China over the same period.
But, said lead author Dr Hsien-Ho Lin, a graduate student in the department of epidemiology at HSPH, and colleagues, large scale programs to help people quit smoking and reduce use of biomass fuels and coals for cooking and heating could significantly reduce these figures.
In China, where half of men smoke and more than 70 per cent of homes burn wood, coal, and crop residue for heating and cooking, respiratory diseases are among the top 10 leading causes of death. Smoking tobacco and inhaling the smoke from the indoor burning of these solid fuels are the main risk factors for COPD and lung cancer, and have also been linked with TB.
For the study, the researchers aimed to predict the effects of risk-factor trends on COPD, lung cancer, and TB by using current and anticipated levels of these diseases, plus representative data on smoking and fuel use. They estimated past trends in smoking and fuel use, and constructed a range of future scenarios.
By re-analysing pooled data from epidemiological studies (including large studies done in China) they assessed the impact of different causes on risk factors for the three diseases.
They then constructed a model to predict future COPD and lung cancer deaths, and the incidence of TB, and worked out what might happen in different scenarios depending on how aggressively China might try to control smoking and fuel use, from moderate, to aggressive to complete cessation.
The results predicted that:
- If smoking and solid fuel use stay at current levels, 65 million people in China will die from COPD and 18 million from lung cancer between 2003 and 2033.
- 82 per cent of COPD deaths and 75 per cent of lung cancer deaths will be due to the combined effects of smoking and solid-fuel use.
- Gradually eliminating smoking and solid fuel use by 2033 could avoid 26 million deaths from COPD and 6.3 million from lung cancer.
- Moderate to aggressive control scenarios would reduce deaths by between 6 and 31 per cent for COPD and 8 to 36 per cent for lung cancer.
- There would be major benefits for TB, more than can be achieved through treatment.
The authors concluded that:
“Reducing smoking and solid-fuel use can substantially lower predictions of COPD and lung cancer burden and would contribute to effective tuberculosis control in China.”
Hsien-Ho Lin said:
“This analysis shows that smoking and fuel use, which affects hundreds of millions of people in China, will be a defining feature of future health in that country.”
The authors suggested the Chinese authorities could introduce tighter regulations and policies to reduce smoking and promote clean household fuels. Such interventions at the public level, and also strategies at the individual level, for instance offering every TB patient the chance to go on a smoking cessation program, could significantly reduce the disease burden from smoking and home use of solid fuel in China.
Senior author Dr Majid Ezzati, who is associate professor of international health at HSPH, said:
“There are proven ways to reduce tobacco smoking and to provide homes with clean-burning energy alternatives.”
” China can save millions of premature deaths from respiratory diseases in the next few decades if it leverages its effective policy system to implement these interventions.”
“Effects of smoking and solid-fuel use on COPD, lung cancer, and tuberculosis in China: a time-based, multiple risk factor, modelling study.”
Hsien-Ho Lin, Megan Murray, Ted Cohen, Caroline Colijn, and Majid Ezzati.
The Lancet Early Online Publication, 4 October 2008
DOI:10.1016/S0140-6736(08)61345-8
Source: Harvard School of Public Health, journal abstract.
Written by: Catharine Paddock, PhD.