Usual alcohol consumption and fatal injuries in middle-aged and older men: A community-based prospective cohort study in Japan

Objectives: This study investigated the association between usual alcohol intake and the risk of fatal unintentional injuries among male subjects who participated in Jichi Medical School Cohort Study. Methods: We conducted a multicenter community-based cohort study in Japan. Among 3789 men aged between 40 and 79 years, information on both frequency and amount of usual alcohol consumption were obtained using a self-administered questionnaire from 1992 through 1995. We confirmed mortality data including causes of death by referring to death certificates. The endpoint measure was death from all unintentional injuries classified as V01-X59 and X85-Y89 according to ICD-10. We used Cox's proportional hazard model to assess the relative risk of fatal unintentional injuries with the adjustment for age, education level, marital status, and employment. Results: During the 11.8 years of mean follow-up time, 45 subjects died of unintentional injuries. Relative risk of fatal unintentional injuries were the highest in ex-drinkers (hazard ratio [HR]: 2.94, 95 % CI: 1.00-8.67). Among current drinkers, relative risk was inversely associated with alcohol intake frequency (HR for occasional drinkers: 2.14, daily drinkers: 0.72). When subjects were categorized by amount of alcohol consumption, moderate drinkers (consumed 23.0-45.7 g/day) showed the lowest (HR: 0.49, 95 % CI: 0.17-1.44), and heavy drinkers (consumed 45.8+ g/day) showed the highest relative risk (HR: 1.65, 95 % CI: 0.68-4.01). Conclusions: In addition to heavy drinkers, occasional drinkers had elevated risk of fatal injuries. The variety of drinking patterns should be considered in preventing fatal injuries in community.