The association of green tea consumption and cardiovascular risk : the Guangzhou biobank cohort study (GBCS)

Abstract

Introduction: Exposure to green tea may have a protective effect on cardiovascular health. However, some other studies showed an increasing risk of cardiovascular disease after drinking tea, the goal of this study is to find out the association between green tea consumption and cardiovascular risk.

Methods: This was a cross-sectional study. I selected 3422 people who didn’t drink tea as the controlled group, and selected 3141 people who drink green tea as the exposed group. Green tea consumption was divided into 5 groups and the first group is the reference group. I made use of generalized linear model to study green tea effect on cardiovascular disease, simultaneously adjusted for potential confounders (age, sex, education, personal income, smoking and alcohol use status, temperature and strength of tea). The outcome variable was the adjusted Framingham Risk Score, which accounted for cardiovascular disease risk by several body indexes such as systolic blood pressure, diastolic blood pressure, HDL-cholesterol, LDL-cholesterol and fasting plasma glucose.

Results: Green tea drinkers and those who did not drink had significant different effect on cardiovascular disease (P<0.001). Green tea consumption was consistent associated with higher Framingham Risk Score, (1-5cups/day compared to none: mean change in Framingham Risk Score:1.280 95%CI 1.062,1.543), systolic blood pressure(1.077,95%CI 0.312,3.719), diastolic blood pressure(1.424, 95%CI 0.751,2.699) ,HDL-cholesterol (0.976, 95%CI 0.953, 0.999), LDL-cholesterol(1.069, 95%CI 1.027,1.113). Risk factors including age, sex, education, personal income, smoking and alcohol use status, physical activity, temperature and strength of green tea were adjusted.

Conclusions: Green tea consumption is associated with increasing risk of cardiovascular disease. Significant difference (p<0.001) was found between green tea consumption and cardiovascular disease in this study.