Objectives: Using common alcohol consumption categories, to conduct a pooled analysis of six ongoing large-scale cohort studies in Japan in order to produce concrete estimates of the quantitative contribution of alcohol consumption to all-cause and major causes of mortality in the Japanese population.
Methods: Of the 309 082 subjects, there were 35 801 deaths during 3 832 285 person-years of follow-up. Using a random-effect model, we conducted a meta-analysis of the HRs of each alcohol consumption category in each study, thereby obtaining pooled estimates for the risk of total and major causes of mortality due to alcohol consumption.
Results: There was a J- or U-shaped association for the risk of total and major causes of mortality in men, and the risk of total and heart disease mortality in women. Compared with non-drinkers, there was a significantly lower risk for total mortality at an alcohol consumption level of <69 g/day, cancer mortality at <46 g/day, heart disease mortality at <69 g/day and cerebrovascular disease mortality at <46 g/day in men, and for total mortality at <23 g/day in women. In addition, mortality risk increased linearly with rising alcohol dose among drinkers. It was estimated that 5% of total mortality, 3% of cancer mortality, 2% of heart disease mortality and 9% of cerebrovascular disease mortality in men, but only 0-1% of these risks in women, could be prevented by reducing alcohol consumption to <46 g/day in men and <23 g/day in women.
Conclusion: Maintaining alcohol consumption below 46 g/day in men and 23 g/day in women appears to minimise the risks of mortality in the Japanese population.