Abstract
Objective
Despite the implementation of the WHO Framework Convention on Tobacco Control (FCTC) program in Iran, the regulation of second-hand smoke (SHS) exposure—an often-overlooked hazard—, still requires improvement. We employed a multi-center case-control study to investigate the association between exposure to secondhand smoke (SHS) from various tobacco products (cigarettes, water-pipes, pipes, and chopogh), opium use, and the risk of lung cancer.
Method
We included 627 lung cancer cases and 3477 controls. Exposure to SHS tobacco and SHS opium was collected through a questionnaire. We used mixed-model logistic regressions to estimate odds ratios (ORs) and 95% confidence intervals (CI).
Result
Among the overall population exposed to second-hand tobacco smoke (SHTS), the odds ratio (OR) compared to those never exposed was 1.35 (95% CI: 1.08–1.71). Never smokers who were ever exposed to second-hand tobacco smoke (SHTS) had 1.69-fold risk of lung cancer compared to those who were never exposed (95% CI: 1.13–2.52). Exposure to SHTS between 2–3 per day (OR = 2.27, 95% CI: 1.13–4.53) and more than three hours per day (OR = 2.29, 95% CI: 1.20–4.37) can increase the risk of lung cancer compared with the no exposure group (P-trend <0.01). We did not observe any association between exposure to second-hand opium smoke (SHOS) and the risk of lung cancer, either in the overall population or among never-smokers.
Conclusion
Our study estimates the impact of second-hand tobacco smoke (SHTS) on lung cancer risk in both the overall population and never-smokers. Additional studies are required to evaluate the association between exposure to second-hand smoke from opium and other type of tobacco, including water-pipe and the risk of lung cancer.
Funder
National Institute for Medical Research Development
Publisher
Public Library of Science (PLoS)
Reference37 articles.
1. Proportion and number of cancer cases and deaths attributable to potentially modifiable risk factors in the United States;F Islami;CA: a cancer journal for clinicians,2018
2. Cancer incidence attributable to lifestyle and environmental factors in Alberta in 2012: summary of results;A Grundy;Canadian Medical Association Open Access Journal,2017
3. Global, regional, and national burden of lung cancer and its attributable risk factors, 1990 to 2017;N Wang;Cancer,2020
4. Lung cancer in never smokers: clinical epidemiology and environmental risk factors;JM Samet;Clinical Cancer Research,2009