Cancer and mortality among users and nonusers of snus

Scandinavian moist snuff (snus) is claimed to be a safer alternative to smoking. We aimed to quantify cancer incidence among male snus users and to shed light on the net health outcome by studying their overall mortality. A cohort, comprised of 9,976 men who participated in a population-based survey, was compiled in 1973-74. Follow-up until January 31, 2002, was accomplished through record-linkages with nation-wide and essentially complete registers of demographics, cancer and causes of deaths. Adjusted relative risks among exposed relative to unexposed men were estimated using Cox proportional hazards regression. The cohort members contributed more than 220,000 person-years at risk for cancer. A statistically significant increase in the incidence of the combined category of oral and pharyngeal cancer among daily users of snus (incidence rate ratio 3.1, 95% confidence interval 1.5-6.6) was found. Overall mortality was also slightly increased (hazard ratio 1.10, 95% confidence interval 1.01-1.21). Although the combined previous literature on snus and oral cancer weigh toward no association, this population-based prospective study provided suggestive evidence of snus-related risks that cannot be lightly ignored. (C) 2008 Wiley-Liss, Inc.