Contemporary associations of exclusive cigarette, cigar, pipe, and smokeless tobacco use with overall and cause-specific mortality in the United States

Background: A growing proportion of tobacco users in the United States use non-cigarette products including cigars, pipes, and smokeless tobacco. Studies examining the disease and mortality risks of these products are urgently needed. Methods: We harmonized tobacco use data from 165 335 adults in the 1991, 1992, 1998, 2000, 2005, and 2010 National Health Interview Surveys. Hazard ratios (HRs) and 95% confidence intervals (CIs) for overall and cause-specific mortality occurring through December 31, 2015, were estimated by exclusive use of cigarettes, cigars, pipes, or smokeless tobacco using Cox proportional hazards regression with age as the underlying time metric and never tobacco users as the referent group. Results: Current use of cigarettes (HR = 2.23, 95% CI = 2.13 to 2.33) and smokeless tobacco (HR = 1.36, 95% CI = 1.17 to 1.59) were each associated with overall mortality. Relative to never tobacco users, higher risks were observed both in daily (HR = 2.34, 95% CI = 2.24 to 2.44) and nondaily (HR = 1.69, 95% CI = 1.54 to 1.86) cigarette smokers, with associations also observed across major smoking-related causes of death. Daily use of smokeless tobacco was also associated with overall mortality (HR = 1.41, 95% CI = 1.20 to 1.66) as was daily use of cigars (HR = 1.52, 95% CI = 1.12 to 2.08). Current smokeless tobacco use was associated with a higher risk of mortality from heart disease and smoking-related cancer, with strong associations observed for cancers of the oral cavity and bladder. Conclusions: Exclusive daily use of cigarettes, cigars, and smokeless tobacco was associated with higher mortality risk. Tobacco control efforts should include cigars and smokeless tobacco.