Swedish snuff and incidence of cardiovascular disease. A population-based cohort study

Background: The relationship between smoking and an increased incidence of cardiovascular diseases is well known. Whether smokeless tobacco (snuff) is related to myocardial infarction (MI) or stroke is still controversial. Aim of this study was to explore whether snuff users have an increased incidence of MI or stroke. Methods: A total of 16 754 women and 10 473 men (aged 45-73 years), without history of cardiovascular disease (CVD), belonging to the population-based "Malmo Diet and Cancer" study were examined. Incidence of MI and stroke were monitored over 10.3 years. Results: Snuff was used by 737 (7.0%) men and 75 (0.4%) women, respectively. Among men, snuff was significantly associated with low occupation level, single civil status, high BMI and with current and former smoking. In women, snuff was associated with lower systolic blood pressure. A total of 964 individuals (3.5%), i.e. 544 men (5.3%) and 420 (2.5%) women suffered a MI during the follow-up period. The corresponding numbers of incident stroke cases were 1048, i.e. 553 men (5.3%) and 495 (3.0%) women, respectively. Snuff was not associated with any statistically significant increased risk of MI or stroke in men or women. The relative risks (RR) in male snuff users compared to non-users were 1.05 (95% confidence interval (CI): 0.8-1.4, p = 0.740) for incident MI and 0.97 (0.7-1.4, p = 0.878) for stroke, after taking age and potential confounders into account. In women none of the 420 (2.5%) women who were snuff users had a MI and only one suffered a stroke during the follow-up. Conclusion: Several life-style risk factors were more prevalent in snuff-users than in non-users. However, the present study does not support any relationship between snuff and incidence of cardiovascular disease in men.