Associations of Coffee, Tea, and Caffeine Intake with Coronary Artery Calcification and Cardiovascular Events

Abstract

Background: Coffee and tea are 2 of the most commonly consumed beverages in the world. The association of coffee and tea intake with coronary artery calcium and major adverse cardiovascular events remains uncertain.

Methods: We examined 6508 ethnically diverse participants with available coffee and tea data from the Multi-Ethnic Study of Atherosclerosis. Intake for each was classified as never, occasional (<1 cup per day), and regular (≥1 cup per day). A coronary artery calcium progression ratio was derived from mixed effect regression models using loge(calcium score+1) as the outcome, with coefficients exponentiated to reflect coronary artery calcium progression ratio versus the reference. Cox proportional hazards analyses were used to evaluate the association between beverage intake and incident cardiovascular events.

Results: Over a median follow-up of 5.3 years for coronary artery calcium and 11.1 years for cardiovascular events, participants who regularly drank tea (≥1 cup per day) had a slower progression of coronary artery calcium compared with never drinkers after multivariable adjustment. This correlated with a statistically significant lower incidence of cardiovascular events for ≥1 cup per day tea drinkers (adjusted hazard ratio 0.71; 95% confidence interval 0.53-0.95). Compared with never coffee drinkers, regular coffee intake (≥1 cup per day) was not statistically associated with coronary artery calcium progression or cardiovascular events (adjusted hazard ratio 0.97; 95% confidence interval 0.78-1.20). Caffeine intake was marginally inversely associated with coronary artery calcium progression.

Conclusions: Moderate tea drinkers had slower progression of coronary artery calcium and reduced risk for cardiovascular events. Future research is needed to understand the potentially protective nature of moderate tea intake.

Keywords: Caffeine; Cardiovascular events; Coffee; Coronary artery calcium; Tea.

Figure 1

Odds ratio of coronary artery calcium scores (CAC score ≥100) by coffee, tea and caffeine consumption. The curves represent the adjusted OR of CAC scores ≥100 Agatston unit) and coffee/tea/caffeine consumption. The reference values (diamond dots) were set at 0 drink per day. The dose response association was estimated by using a linear and a cubic spline term for coffee/tea consumption in the multivariable logistic regression. The model adjusted for age, sex, race/ethnicity, education, smoking (never, former, current), physical activity, total fat, alcohol consumption, fruits quartiles, vegetables quartiles, red meat quartiles, systolic and diastolic blood pressures, use of antihypertensive medications, lipid-lowering medication, anti-diabetic medication, BMI, family history of CHD, diabetes, HDL-cholesterol, total cholesterol, and triglyceride. For daily caffeine consumption, curves represent adjusted odds ratio (solid line) and their 95% confidence intervals (dashed lines) based on restricted cubic splines for caffeine intake among all participants with knots at the 5th, 35th, 65th and 95th percentiles of their sample distributions (corresponding to 0.5, 59, 161, 626 mg). The reference values (diamond dots) were set at 10^th percentile (5 mg).

Figure 2

Change log (coronary artery calcium scores+1) during follow up among all participants by coffee, tea and caffeine consumption at baseline. The curves represent the adjusted change of CAC scores and coffee/tea consumption. The dose response association of coffee/tea consumption was estimated by using a linear and a cubic spline term for coffee/tea consumption in the mixed effect regression. The reference values (diamond dots) were set at 0 drink per day. For caffeine intake, knots were set at the 5th, 35th, 65th and 95th percentiles of their sample distributions (corresponding to 0.5, 59, 161, 626 mg). The reference values (diamond dots) were set at 10th percentile (5 mg). The model adjusted for age, sex, race/ethnicity, education, smoking (never, former, current), physical activity, total fat, alcohol consumption, fruits quartiles, vegetables quartiles, red meat quartiles, systolic and diastolic blood pressures, use of antihypertensive medications, lipid-lowering medication, anti-diabetic medication, BMI, family history of CHD, diabetes, HDL-cholesterol, total cholesterol, and triglyceride.