Tea's Effect on Atherosclerosis Pilot Study (TEA Study)

Tea is widely thought to have health benefits, particularly on cardiovascular disease (CVD). The investigator's group recently found that intake of 2 or more cups of tea per day was associated with a 44% lower long-term mortality rate than abstention from tea among 1900 patients hospitalized with myocardial infarction. Short-term trials support a benefit of tea on endothelial function, but long-term randomized trials of tea intake on CVD and atherosclerosis are needed to test the effects of tea definitively. The researchers propose a proof-of-principle pilot study of the effect of long-term tea intake on atherosclerosis. From a large hospital-based primary care practice, 30 patients at high risk for CVD will be recruited and randomized to a six-month period of consumption of 3 cups per day of either tea, supplied as black tea solids readily dissolved in hot or cold liquid, or water. The polyphenol content of these solids will be confirmed at baseline, and a single batch of tea throughout the study will be used. At baseline and after 6 months, aortic atherosclerosis using magnetic resonance imaging, an accurate and reproducible method for measurement of arterial plaque size, will be assessed. Adherence using urinary catechins, the primary flavonoids in tea, will be measured. The primary outcomes will be compliance with tea intake and 2 MRI examinations. As secondary outcomes, standard and novel cardiovascular risk markers, including inflammatory, prothrombotic, fibrinolytic, and metabolic factors will be measured. The researchers will also assess the effects of tea consumption on oxidizability of LDL and VLDL cholesterol, using a novel affinity-column chromatography approach, and on endothelial integrity, as assessed by serum markers of endothelial function. If successful, this pilot study will form the basis for a larger, long-term randomized trial to determine the effect of tea consumption on progression of atherosclerosis.