Marzieh Araghi1, Maria Rosaria Galanti1,2, Michael Lundberg1, Zhiwei Liu3, Weimin Ye3, Anton Lager1,2, Gunnar Engström4, Lars Alfredsson5, Anders Knutsson6, Margareta Norberg7, Patrik Wennberg8, Ylva Trolle Lagerros9,10, Rino Bellocco3,11, Nancy L Pedersen3, Per-Olof Östergren12, Cecilia Magnusson1,2. 1. Department of Public Health Sciences, Karolinska Institutet, Stockholm, Sweden. 2. Centre for Epidemiology and Community Medicine, Stockholm Health Care District, Sweden. 3. Department of Medical Epidemiology and Biostatistics, Karolinska Institutet, Sweden. 4. Department of Clinical Sciences, Lund University, Sweden. 5. Institute of Environmental Medicine, Karolinska Institutet, Sweden. 6. Department of Health Sciences, Mid Sweden University, Sweden. 7. Department of Public Health and Clinical Medicine, Umeå University, Sweden. 8. Division of Family Medicine, Umeå University, Sweden. 9. Clinical Epidemiology Unit, Karolinska Institutet, Sweden. 10. Clinic of Endocrinology, Metabolism and Diabetes, Karolinska University Hospital Huddinge, Sweden. 11. Department of Statistics and Quantitative Methods, University of Milano-Bicocca, Milan, Italy. 12. Social Medicine and Global Health, Lund University, Sweden.
Abstract
Aims: Worldwide, smokeless-tobacco use is a major risk factor for oral cancer. Evidence regarding the particular association between Swedish snus use and oral cancer is, however, less clear. We used pooled individual data from the Swedish Collaboration on Health Effects of Snus Use to assess the association between snus use and oral cancer. Methods: A total of 418,369 male participants from nine cohort studies were followed up for oral cancer incidence through linkage to health registers. We used shared frailty models with random effects at the study level, to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) adjusted for confounding factors. Results: During 9,201,647 person-years of observation, 628 men developed oral cancer. Compared to never-snus use, ever-snus use was not associated with oral cancer (adjusted HR 0.90, 95% CI: 0.74, 1.09). There were no clear trends in risk with duration or intensity of snus use, although lower intensity use (⩽ 4 cans/week) was associated with a reduced risk (HR 0.65, 95% CI: 0.45, 0.94). Snus use was not associated with oral cancer among never smokers (HR 0.87, 95% CI: 0.57, 1.32). Conclusions: Swedish snus use does not appear to be implicated in the development of oral cancer in men.
Aims: Worldwide, smokeless-tobacco use is a major risk factor for oral cancer. Evidence regarding the particular association between Swedish snus use and oral cancer is, however, less clear. We used pooled individual data from the Swedish Collaboration on Health Effects of Snus Use to assess the association between snus use and oral cancer. Methods: A total of 418,369 male participants from nine cohort studies were followed up for oral cancer incidence through linkage to health registers. We used shared frailty models with random effects at the study level, to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) adjusted for confounding factors. Results: During 9,201,647 person-years of observation, 628 men developed oral cancer. Compared to never-snus use, ever-snus use was not associated with oral cancer (adjusted HR 0.90, 95% CI: 0.74, 1.09). There were no clear trends in risk with duration or intensity of snus use, although lower intensity use (⩽ 4 cans/week) was associated with a reduced risk (HR 0.65, 95% CI: 0.45, 0.94). Snus use was not associated with oral cancer among never smokers (HR 0.87, 95% CI: 0.57, 1.32). Conclusions: Swedish snus use does not appear to be implicated in the development of oral cancer in men.