Background: The scientific evidence on cardiovascular risks associated with long-term use of snuff is limited and inconclusive. The use of this smokeless tobacco has increased in recent decades, and adverse health effects associated with snuff use could be of great public health concern.
Objective: We aimed to study whether long-term use of snuff affects the risk of myocardial infarction.
Design: Between 1978 and 1993 all construction workers in Sweden were offered repeated health check-ups by the Swedish Construction Industry's Organization for Working Environment Safety and Health. A cohort was created with information on tobacco use and other risk factors, collected through questionnaires.
Setting: In total, 118,395 nonsmoking men without a history of myocardial infarction were followed through 2004. Information on myocardial infarction morbidity and mortality was obtained from national registers. Relative risk estimates were derived from Cox proportional hazards regression model, with adjustment for age, body mass index and region of residence.
Results: Almost 30% of the men had used snuff. In total, 118 395 nonsmoking men without a history of myocardial infarction were followed through 2004. The multivariable-adjusted relative risks for ever snuff users were 0.91 (95% confidence interval, 0.81-1.02) for nonfatal cases and 1.28 (95% confidence interval, 1.06-1.55) for fatal cases. Heavy users (>or=50 g day(-1)) had a relative risk of fatal myocardial infarction of 1.96 (95% confidence interval, 1.08-3.58). Snuff use increased the probability of mortality from cardiovascular disease amongst nonfatal myocardial infarction patients.
Conclusion: Our results indicate that snuff use is associated with an increased risk of fatal myocardial infarction.