Smokeless tobacco use and increased cardiovascular mortality among Swedish construction workers.

OBJECTIVES: Little is known about the risks of cardiovascular disease associated with the use of smokeless tobacco, which produces blood nicotine levels similar to those caused by cigarette smoking. METHODS: Male Swedish construction industry employees (n = 135,036) who attended a health examination were followed by studying cause-specific mortality during a 12-year period. The study population comprised 6297 smokeless tobacco users, 14,983 smokers of fewer than 15 cigarettes per day, 13,518 smokers of 15 or more cigarettes per day, 17,437 ex-smokers, 50,255 "other" tobacco users, and 32,546 nonusers. RESULTS: The age-adjusted relative risk of dying from cardiovascular disease was 1.4 for smokeless tobacco users and 1.9 for smokers of 15 or more cigarettes per day, compared with nonusers. Among men aged 35 through 54 years at the start of follow-up, the relative risk was 2.1 for smokeless tobacco users and 3.2 for smokers. When data were adjusted for body mass index, blood pressure, and history of heart symptoms, the results were essentially unchanged. Cancer mortality was not raised in smokeless tobacco users. CONCLUSIONS: Both smokeless tobacco users and smokers face a higher risk of dying from cardiovascular disease than nonusers. Although the risk is lower for smokeless tobacco users than for smokers, the excess risk gives cause for preventive actions.