- Japan Epidemiological Association
- Journal of Epidemiology (ISSN:09175040)
- pp.JE20170330, (Released:2018-05-31)
Background: Annually, more than 1.2 million deaths due to road traffic accidents occur worldwide. Although previous studies have examined the association between cigarette smoking and injury death, the mortality outcome often included non-traffic accident-related deaths. This study aimed to examine the association between cigarette smoking and traffic accident death.Methods: We conducted a prospective cohort study using data from the Ibaraki Prefectural Health Study conducted between 1993 and 2013. The cohort included 97,078 adults (33,138 men and 63,940 women) living in Ibaraki Prefecture, who were aged 40–79 years at an annual health checkup in 1993. We divided participants into four smoking status groups: non-smokers, ex-smokers and current smokers who smoked <20 and ≥20 cigarettes per day. Hazard ratios (HRs) of traffic accident death were calculated using a Cox proportional hazards model.Results: During 20 years of follow-up, average person-year of follow-up were 16.8 and 18.2 in men and women, respectively. Among men, after adjusting for age and alcohol intake, compared to non-smokers, HRs for traffic accident death among current smokers of <20 cigarettes/day and ≥20 cigarettes/day were 1.32 (95% confidence interval (CI), 0.79–2.20) and 1.54 (95% CI, 0.99–2.39), respectively. In contrast, among women, we found no association between smoking status and traffic accident deaths.Conclusion: In this prospective cohort study, we found a positive association, though marginally significant, between smoking and traffic accident death among men in Japan. Among women, because smaller number of death among smokers, adequate estimation could not be obtained.