Coffee, green tea, black tea and oolong tea consumption and risk of mortality from cardiovascular disease in Japanese men and women
Author: Yohei Mineharu, and Akio Koizumi, and Yasuhiko Wada, and Hiroyasu Iso, and Yoshiyuki Watanabe, and Chigusa Date, and Akio Yamamoto, and Shogo Kikuchi, and Yutaka Inaba, and Hideaki Toyoshima, and Takaaki Kondo, and Akiko Tamakoshi
Background: The effects of coffee and green, black and oolong teas and caffeine intake on cardiovascular disease (CVD) mortality have not been well defined in Asian countries. Methods: To examine the relationship between consumption of these beverages and risk of mortality from CVD, we prospectively followed 76,979 individuals aged 40-79 y free of stroke, coronary heart disease (CHD), and cancer at entry. Daily consumption of beverages was assessed by questionnaires. Results: We documented 1362 deaths from strokes and 650 deaths from CHD after 1,010,787 person-years of follow-up. Compared with non-drinkers of coffee, the multivariable hazard ratios (HRs) and 95% confidence interval for those drinking 1-6 cups/wk, 1-2 cups/d and a ‰Ψ3 cups/d were 0.78 (0.50-1.20), 0.67 (0.47-0.96) and 0.45 (0.17-0.87) for strokes among men (p=0.009 for trend). Compared with non-drinkers of green tea, the multivariable HRs for those drinking 1-6 cups/wk, 1-2 cups/d, 3-5 cups/d and a ‰Ψ6 cups/d were 0.34 (0.06-1.75), 0.28 (0.07-1.11), 0.39 (0.18-0.85), and 0.42 (0.17-0.88) for CHD among women (p=0.038 for trend). As for oolong tea, the multivariable HRs of those drinking 1-6 cups/wk and a ‰Ψ1 cups/d were 1.00 (0.65-1.55) and 0.39 (0.17-0.88) for total CVD among men (p=0.049 for trend). Risk reduction for total CVD across categories of caffeine intake was most prominently observed in the second highest quintile with a 38% lower risk among men and 22% among women. Conclusions: Consumption of coffee, green tea and oolong tea and total caffeine intake was associated with a reduced risk of mortality from CVD.