Increased tea consumption is associated with decreased arterial stiffness in a Chinese population.
BACKGROUND
Tea has attracted considerable attention for its potential cardioprotective effects. The primary chemical components of tea are thought to have a beneficial effect by reducing arterial stiffness. The objective of this study was to assess the association between tea consumption and brachial-ankle pulse wave velocity (baPWV) in a relatively healthy Chinese population.


METHODS
We enrolled 3,135 apparently healthy subjects from October 2006 to August 2009. Subjects taking medication for diabetes, hypertension, or hyperlipidemia, or with a history of cardiovascular disease, were excluded from the study. The subjects were categorized into three groups according to their tea-drinking habits: (1) none to low (n = 1615), defined as non-habitual tea drinkers, or drinking for <1 year, or drinking ≤150 mL per day for ≥1 year ; (2) moderate tea consumption, defined as drinking for ≥1 year and consumption between 151 and 450 mL per day; and (3) heavy tea consumption, defined as a drinking for ≥1 year and consumption >450 mL per day. Multiple logistic regression was used to determine whether different levels of consumption were independently associated with the highest quartile of baPWV values, defined as ≥1428.5 cm/s.


RESULTS
Of the 3,135 subjects, 48.5% had drunk >150 mL of tea per day for at least 1 year. In multivariate regression analysis with adjustment for co-variables, including, age, sex, current smoking, alcohol use, habitual exercise, total cholesterol/high-density lipoprotein cholesterol (TC/HDL-C) ratio >5, obesity, newly diagnosed hypertension and diabetes, subjects with high tea consumption had a decreased risk of highest quartile of baPWV by 22% (odds ratio = 0.78, 95% confidence interval = 0.62-0.98, p = 0.032), while subjects with moderate tea consumption did not (p = 0.742), as compared subjects with none to low tea consumption.


CONCLUSIONS
High, but not moderate, habitual tea consumption may decrease arterial stiffness.
Department of Family Medicine, Tainan Municipal An-Nan Hospital- China Medical University, Taiwan.
Chung-Hao
CH
Li
Department of Family Medicine, National Cheng Kung University Hospital, Tainan, Taiwan ; Department of Family Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Yi-Ching
YC
Yang
Department of Family Medicine, National Cheng Kung University Hospital, Tainan, Taiwan ; Department of Family Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Jin-Shang
JS
Wu
Department of Family Medicine, National Cheng Kung University Hospital, Tainan, Taiwan.
Ying-Hsiang
YH
Huang
Department of Family Medicine, National Cheng Kung University Hospital, Tainan, Taiwan.
Chih-Ting
CT
Lee
Department of Family Medicine, National Cheng Kung University Hospital, Tainan, Taiwan ; Department of Family Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Feng-Hwa
FH
Lu
Department of Family Medicine, National Cheng Kung University Hospital, Tainan, Taiwan ; Department of Family Medicine, College of Medicine, National Cheng Kung University, Tainan, Taiwan.
Chih-Jen
CJ
Chang
D000328:Adult; D000368:Aged; D055109:Ankle Brachial Index / Q000706:statistics & numerical data; D044466:Asian People / Q000706:statistics & numerical data; D002681:China; D003920:Diabetes Mellitus / Q000175:diagnosis / Q000503:physiopathology; D005260:Female; D006801:Humans; D006973:Hypertension / Q000175:diagnosis / Q000503:physiopathology; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009765:Obesity / Q000175:diagnosis / Q000503:physiopathology; D058729:Peripheral Arterial Disease / Q000208:ethnology / Q000503:physiopathology* / Q000517:prevention & control*; D063177:Pulse Wave Analysis; D012307:Risk Factors; D013662:Tea; D059289:Vascular Stiffness / Q000502:physiology*
D013662:Tea