Smokeless tobacco (snus) and risk of heart failure: results from two Swedish cohorts

BACKGROUND: Oral moist snuff (snus) is discussed as a safer alternative to smoking, and its use is increasing. Based on its documented effect on blood pressure, we hypothesized that use of snus increases the risk of heart failure. DESIGN: Two independent Swedish prospective cohorts; the Uppsala Longitudinal Study of Adult Men (ULSAM), a community-based sample of 1076 elderly men, and the Construction Workers Cohort (CWC), a sample of 118,425 never-smoking male construction workers. METHODS: Cox proportional hazards models were used to investigate possible associations of snus use with risk of a first hospitalization for heart failure. RESULTS: In ULSAM, 95 men were hospitalized for heart failure, during a median follow up of 8.9 years. In a model adjusted for established risk factors including past and present smoking exposure, current snus use was associated with a higher risk of heart failure [hazard ratio (HR) 2.08, 95% confidence interval (CI) 1.03-4.22] relative to non-use. Snus use was particularly associated with risk of non-ischaemic heart failure (HR 2.55, 95% CI 1.12-5.82). In CWC, 545 men were hospitalized for heart failure, during a median follow up of 18 years. In multivariable-adjusted models, current snus use was moderately associated with a higher risk of heart failure (HR 1.28, 95% CI 1.00-1.64) and non-ischaemic heart failure (HR 1.28, 95% CI 0.97-1.68) relative to never tobacco use. CONCLUSION: Data from two independent cohorts suggest that use of snus may be associated with a higher risk of heart failure.