The interactions of tobacco smoking and other agents in cancer etiology

Our plain-English summary of The interactions of tobacco smoking and other agents in cancer etiology, by R. Saracci (Epidemiologic Reviews, 1987).

The study

• Author: R. Saracci
• Journal: Epidemiologic Reviews
• Published: 1987;9:175-93
• Type of article: Review
• Cited by: 121 articles, as counted by NIH iCite
• Read it: PubMed · Publisher
• In J-M's library: Johns-Manville's company medical library held a copy (J-M no. 000353).

In plain English

This 1987 article was a review, not a new study. The author examined published studies on how tobacco smoking combines with other agents in causing cancer. The agents were asbestos, radon, atomic bomb radiation, nickel, arsenic, chloromethylethers, aromatic amines and alcohol. The asbestos studies covered miners and millers, factory workers, and insulators and shipyard workers. They included 34 lung cancer cases among nonsmoking asbestos workers, plus 53 in a mixed group of nonsmokers and light smokers. In most asbestos studies, the joint effect on lung cancer fell in the multiplicative range, but the pattern varied. The interaction was weak among Canadian chrysotile miners and millers and more than multiplicative among Western Australian crocidolite miners and millers. None of the asbestos studies could formally reject a multiplicative pattern at the 0.05 significance level. One set of data, from US and Canadian insulation workers, showed a substantially decreasing lung cancer relative risk with time since quitting smoking. The author concluded that a multiplicative relation was either an approximately satisfactory description of the data or an upper limit. The author noted that statistical tests for interaction have low power.

We wrote this plain-English summary from the full article with the help of AI, and a second AI model checked each sentence against the article. It is not the authors' wording; the abstract and the article are their own account.

What the study did and found

• Design: Review of published epidemiologic studies on interactions between tobacco smoking and other agents in cancer causation
• Who was studied: For asbestos: published studies of miners and millers, workers manufacturing asbestos products, and user workers (mostly insulators in building and shipyards), plus case-control studies. In total these included 34 lung cancer cases among nonsmoking asbestos workers and 53 cases in a mixed category of nonsmokers and low-level smokers. Studies of radon-exposed miners, atomic bomb survivors, other occupational groups and alcohol drinkers were also reviewed.
• Exposure: Tobacco smoking combined with asbestos (chrysotile, crocidolite and amosite), radon daughters, gamma and neutron radiation, nickel, arsenic, chloromethylethers, aromatic amines, or alcohol
• Main results:
  • In most of the asbestos studies reviewed, the size of the asbestos-smoking interaction on lung cancer was in the multiplicative region. This was not uniform across studies, workplaces or fiber types.
  • Among Canadian chrysotile miners and millers, the interaction was weak, accounting for less than 25 per cent of the total excess lung cancer due to joint exposure
  • Among crocidolite underground miners and millers of Western Australia, a more than multiplicative interaction was observed. A detailed analysis did not reject the simpler multiplicative hypothesis.
  • At one UK factory, the original study's authors asked whether the weaker interaction in the second follow-up might partly reflect smoking misclassification. Of 15 subjects found to be nonsmokers, eight were classified as nonsmokers by both questionnaire and later informants.
  • None of the asbestos studies gave enough evidence to formally reject a multiplicative interaction at p = 0.05
  • In most asbestos exposure circumstances studied, the share of total excess risk due to interaction was at least 25 per cent and often above 50 per cent
  • One set of data, from insulators in the United States and Canada, showed a substantially decreasing lung cancer relative risk with time since quitting smoking
  • Two studies of asbestos, smoking, alcohol and laryngeal cancer had data inadequate to assess an asbestos-smoking interaction
  • For nickel, the limited data available supported a simple additive relation with smoking for lung cancer
• The authors' conclusion: The author concluded that no agent had a consistent, statistically significant antagonistic or more than multiplicative interaction with smoking. A multiplicative relation could be regarded either as an approximately satisfactory representation of the data or, at worst, as an upper limit of the interaction's strength.
• Limitations the authors state:
  • Statistical tests for interactions have low power
  • Published reports did not give enough detail to judge the kind and size of possible biases
  • Some confounding may have affected the reported results
  • For some asbestos studies, a relative risk of 10 for smokers versus nonsmokers was assumed rather than derived from the data

Topics

Medical terms in this study, explained in our Lexicon: Etiology.

Related studies

• Interaction between tobacco smoking and occupational exposures in the causation of lung cancer — K. Steenland, M. Thun (1986)
• Absence of multiplicative interactions between occupational lung carcinogens and tobacco smoking: a systematic review involving asbestos, crystalline silica and diesel engine exhaust emissions — M. El Zoghbi, P. Salameh, et al. (2017)
• The joint effect of asbestos exposure, tobacco smoking and alcohol drinking on laryngeal cancer risk: evidence from the French population-based case-control study, ICARE — G. Menvielle, A. Fayossé, et al. (2016)
• Risk of human health by particulate matter as a source of air pollution--comparison with tobacco smoking — M. Enomoto, W.J. Tierney, et al. (2008)
• Phenotypes of lung cancer and statistical interactions between tobacco smoking and occupational exposure to asbestos and crystalline silica from a large case-only study: The CaProMat study — M. El Zoghbi, P. Salameh, et al. (2017)
• Arsenic, tobacco smoke, and occupation: associations of multiple agents with lung and bladder cancer — C. Ferreccio, Y. Yuan, et al. (2013)

Browse return to medical research.