Abstract
Background
This study was conducted to examine the impacts of coffee and green tea consumption on cardiovascular disease (CVD) mortality among people with severe hypertension.
Methods and Results
In the JACC (Japan Collaborative Cohort Study for Evaluation of Cancer Risk), 18 609 participants (6574 men and 12 035 women) aged 40 to 79 years at baseline who completed a lifestyle, diet, and medical history questionnaire, and health examinations, were followed up until 2009. We classified the participants into four blood pressure (BP) categories: optimal and normal BP, high‐normal BP, grade 1 hypertension, and grade 2–3 hypertension. A Cox proportional hazard model was used to calculate the multivariable hazard ratios with 95% CIs of CVD mortality. During the 18.9 years of median follow‐up, a total of 842 CVD deaths were documented. Coffee consumption was associated with an increased risk of CVD mortality among people with grade 2–3 hypertension; the multivariable hazard ratios (95% CI) of CVD mortality were 0.98 (0.67–1.43) for <1 cup/day, 0.74 (0.37–1.46) for 1 cup/day, and 2.05 (1.17–3.59) for ≥2 cups/day, compared with non–coffee drinkers. Such associations were not found among people with optimal and normal, high‐normal BP, and grade 1 hypertension. Green tea consumption was not associated with an increased risk of CVD across any BP categories.
Conclusions
Heavy coffee consumption was associated with an increased risk of CVD mortality among people with severe hypertension, but not people without hypertension and with grade 1 hypertension. In contrast, green tea consumption was not associated with an increased risk of CVD mortality across all categories of BP.
Keywords: coffee, cohort study, diet, green tea, hypertension
Subject Categories: Epidemiology, Diet and Nutrition, Lifestyle, Hypertension, High Blood Pressure
Nonstandard Abbreviations and Acronyms
- DBP
diastolic blood pressure
- JACC
Japan Collaborative Cohort Study for Evaluation of Cancer Risk
- SBP
systolic blood pressure
Clinical Perspective.
What Is New?
Heavy coffee consumption was associated with an increased risk of cardiovascular disease mortality among people with severe hypertension but not in those without hypertension or with grade 1 hypertension.
In contrast, green tea consumption was not associated with an increased risk of cardiovascular disease mortality across all blood pressure categories.
What Are the Clinical Implications?
Heavy coffee consumption can increase the risk of cardiovascular disease mortality among people with severe hypertension, while green tea consumption does not increase the risk of cardiovascular disease mortality.
The present study may support the assertion that heavy coffee consumption should be avoided among people with severe hypertension.
Coffee consumption can reduce the risk of incident hypertension 1 and mortality among the general population, 2 , 3 , 4 while it can lead to a short‐term increase in blood pressure (BP) among people with hypertension. 5 In an experimental study, Hartley et al compared the acute effects of the oral administration of caffeine on arterial BP among 182 men divided into 5 hypertension risk groups. 6 The most substantial acute response of BP elevation to caffeine ingestion was observed among diagnosed hypertensive groups, followed by stage 1 (systolic blood pressure [SBP] 140–159 mm Hg or diastolic blood pressure [DBP] 90–99 mm Hg) and high‐normal (SBP 130–139 mm Hg or DBP 85–89 mm Hg) groups and then by normal (SBP 120–129 mm Hg or DBP 80–85 mm Hg) and optimal (SBP <120 mm Hg and DBP <80 mm Hg) groups. As an acute increase in BP can increase an individual's risk of cardiovascular disease (CVD), 7 these results can suggest that the preventive effect of caffeinated coffee consumption depends on the drinkers' BP level and applies only to people without severe hypertension.
Caffeinated green tea consumption has been shown to lower BP among people with prehypertension and stage 1 hypertension 8 and reduce the risk of mortality from all causes and CVD among those with CVD 9 and the general population. 10 We recently reported that ≥7 cups of green tea consumed per day was associated with a reduced risk of all‐cause mortality among people with a history of stroke or myocardial infarction by 62% and 53%, respectively, compared with non‐drinkers. 9 Approximately 50% of the stroke and myocardial infarction survivors in that study had a history of hypertension, suggesting that green tea consumption may also reduce the risk of mortality among people with hypertension.
To the best of our knowledge, only 1 study of a small number of participants examined the associations between habitual coffee consumption and the risk of CVD mortality or incidence among people with hypertension across multiple BP categories. 11 In particular, little is known about whether the protective effect of coffee consumption exists for people with severe hypertension. Moreover, no study has examined whether the association between green tea consumption and the risk of CVD mortality varies across the BP categories. Therefore, this study aimed to examine and compare the effect of green tea or coffee consumption on the risk of CVD mortality across multiple BP categories in a large long‐term cohort study of Japanese men and women.
METHODS
The data that support the findings of this study are available from the corresponding author upon reasonable request.
Study Population
The JACC (Japan Collaborative Cohort Study for Evaluation of Cancer Risk) is a large, nationwide, community‐based prospective study that was established between 1988 and 1990 and enrolled 110 585 individuals (46 395 men and 64 190 women) aged 40 to 79 years, living in 45 communities across Japan. The methodology of the JACC has been described elsewhere. 12 In brief, a total of 110 585 participants from 45 communities were asked to complete self‐administered questionnaires, including demographic characteristics, medical history, lifestyle, and diet.
Among these participants, BP was measured for 29 928 participants (10 884 men and 19 044 women) from 30 communities who underwent health examinations conducted by municipal governments (Figure). We excluded 8267 participants (3160 men and 5107 women) in 6 communities because the questions on the frequency of green tea or coffee consumption or the questions on the number of cups of green tea and coffee consumed per day were not included in the questionnaire. Furthermore, we excluded 2483 participants (918 men and 1565 women) because of missing responses to questions about green tea and coffee consumption; 567 participants (232 men 335 women) who reported a history of stroke, coronary heart disease, or cancer at baseline; and 2 participants with outliers of pulse pressure (≤10 mm Hg). Thus, a total of 18 609 participants (6574 men and 12 035 women) from 24 communities were included in the analyses. Before completing the questionnaire, the participants or community representatives provided informed consent to participate in this epidemiological study according to the guidelines of the Council for International Organizations of Medical Sciences. Informed consent was obtained from each participant in 18 of the 24 communities. In the remaining 6 areas, group consent was obtained from each area leader. The study protocol was approved by the Ethics Committees of Hokkaido University (reference number: 14–044), Nagoya University (reference number: 177 and 227), and Osaka University (reference number: 14285–8), and in compliance with the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.
Figure . Flowchart of study population selection.
JACC indicates Japan Collaborative Cohort Study for Evaluation of Cancer Risk.
Assessment of Blood Pressure
Baseline BP was measured by trained staff using a standard mercury sphygmomanometer on the right arm of seated participants after a 5‐minute rest. In principle, BP was measured twice and averaged according to the guideline from the Japanese Association for Cerebro‐Cardiovascular Disease Control. According to the modified classification of the 2018 European Society of Hypertension–European Society of Cardiology guidelines, 13 we classified the participants into 5 BP categories: optimal and normal BP, high‐normal BP, grade 1 hypertension, grade 2 hypertension, and grade 3 hypertension. Optimal and normal BP was defined as SBP <130 mm Hg and DBP <85 mm Hg, high normal BP as SBP 130–139 mm Hg or DBP 85–89 mm Hg, grade 1 hypertension as SBP 140–159 mm Hg or DBP 90–99 mm Hg, grade 2 hypertension as SBP of 160–179 mm Hg or DBP of 100–109 mm Hg, and grade 3 hypertension as SBP ≥180 mm Hg or DBP ≥110 mm Hg. Because of the relatively low percentage of the categories of participants with grade 3 hypertension, the categories of grade 2 and 3 hypertension were combined.
Assessment of Coffee and Green Tea Consumption
We asked participants about their frequency and amount of coffee and green tea consumed using the following choices: “almost every day,” “3 to 4 cups per week,” “1 to 2 cups per week,” “1 to 2 cups per month,” and “almost never.” For those who answered “almost every day,” we asked questions about the number of cups consumed per day. According to their responses to these two questions, we classified their responses into 4 levels for coffee consumption (occasionally or none, <1, 1, and ≥2 cups per day) and into 6 levels for green tea consumption (occasionally or none, <1, 1–2, 3–4, 5–6, and ≥7 cups per day). Coffee type, such as decaffeinated or caffeinated, was not asked because decaffeinated coffee was not common, and most participants consumed instant or drip brewed coffee during the baseline survey period in Japan. The validation study of the food frequency questionnaire used in this cohort was conducted during the 1‐year follow‐up period, indicating a relatively higher correlation coefficient of coffee (Spearman's correlation coefficient, 0.86) and green tea (Spearman's correlation coefficient, 0.62). 14
Assessment of Confounding Variables
Height, weight, and total cholesterol levels were measured during the health examinations. Other demographic, lifestyle, and biological factors were derived from a self‐administered questionnaire at baseline: age, sex, history of diabetes, use of antihypertensive medication, smoking and alcohol drinking status, exercise and walking habits, mental status, educational level, occupation, and eating habits. Body mass index was calculated as body weight (kg) divided by height squared (m2).
Mortality Surveillance
To determine the cause of death, a systematic review of death certificates was conducted for each area. Mortality data were sent centrally to the Ministry of Health and Welfare through the local public health center, and the underlying cause of death was coded for the National Vital Statistics according to the International Classification of Diseases, Tenth Revision (ICD‐10). The end point of death in this study was CVD mortality defined as ICD‐10 codes: I01 to I99. The follow‐up was finished by the end of 1999 in 2 areas, the end of 2003 in 1 area, the end of 2008 in 2 areas, and the end of 2009 in the rest of the areas. The date of moving from the community was verified using the population registration documents. Participants were censored when they moved from the areas.
Statistical Analysis
Person‐years of follow‐up were calculated as the duration from the date of the baseline questionnaire to the date of death, emigration from the community, or the end of follow‐up, whichever occurred first. Age‐adjusted mean values and proportions of cardiovascular risk factors were calculated using generalized linear models. Hazard ratios with 95% CIs of CVD mortality were calculated for each BP category using Cox proportional hazards regression models according to coffee and green tea consumption. We confirmed no violation for the proportional hazard assumption in all models. We adjusted for age (continuous); sex (women or men); use of antihypertensive medication (yes or no); history of diabetes (yes or no); body mass index (sex‐specific quintile); total cholesterol level (mg/dL; sex‐specific quintile); smoking status (never, ex‐smoker, current smoker of 1–19 cigarettes per day, or current smoker of ≥20 cigarettes per day); alcohol consumption (never drinker, ex‐drinker, current drinker of 0.1–45.9 g ethanol per day, or ≥46.0 g ethanol per day); hours of exercise (almost never, 1–4 hours, or ≥5 hours per week); hours of walking (almost never, 0.5 hours, or >0.5 hours per day); perceived mental stress (low, moderate, or high); educational level (≤18 or ≥19 years of age upon completion of education); employment status (unemployed or employed); frequency of consuming vegetables, fish, fruits, and soybean intakes (quintile); and coffee consumption or green tea consumption. The number of missing for each variable was as follows: use of antihypertensive medication (n=795), a history of diabetes (n=935), body mass index (n=35), total cholesterol level (n=1005), smoking (n=1126) and alcohol drinking status (n=1572), exercise (n=893) and walking habits (n=834), mental status (n=1275), educational level (n=883), employment status (n=519), and eating habits (vegetable, n=1995; fish, n=1903; fruit, n=1816; soy; n=1142). The proportion of missing for each variable was at most about 10% of the study participants. To account for missing values for each covariate, dummy variables for missing were created and put into the Cox model. In the sensitivity analysis, we repeated the same analysis by using multiple imputation techniques (10 repetitions) to impute missing covariates. SAS version 9.4 (SAS, Inc., Cary, NC) was used for the statistical analyses.
RESULTS
Table 1 shows the age‐adjusted baseline characteristics of the participants by coffee consumption in each BP category. People with more frequent coffee consumption were more likely to be younger, be current smokers, be current drinkers, eat fewer vegetables, and have higher total cholesterol levels and lower SBP regardless of the BP category.
Table 1.
Age‐Adjusted Baseline Characteristics of Participants by Coffee Consumption in Each Blood Pressure Category
| Coffee consumption | P for trend | ||||
|---|---|---|---|---|---|
| Blood pressure category | None | <1 cup/d | 1 cup/d | ≥2 cups/d | |
| Optimal and normal | |||||
| No. of participants | 2459 | 3186 | 1204 | 1473 | |
| Age, y | 56.7 | 53.8 | 52.4 | 50.4 | <0.001 |
| Sex, male, % | 26.6 | 32.6 | 25.2 | 34.8 | <0.001 |
| Systolic blood pressure, mm Hg | 115.6 | 115.4 | 114.9 | 114.9 | 0.009 |
| Diastolic blood pressure, mm Hg | 71.0 | 71.3 | 70.7 | 70.9 | 0.29 |
| Total cholesterol, mg/dL | 192.2 | 192.6 | 195.6 | 196.2 | <0.001 |
| Body mass index, kg/m2 | 22.4 | 22.6 | 22.3 | 22.3 | 0.06 |
| Antihypertensive medication, % | 4.4 | 3.2 | 3.2 | 2.6 | 0.008 |
| History of diabetes, % | 2.6 | 2.2 | 1.4 | 2.3 | 0.54 |
| Current smoker, % | 14.7 | 18.8 | 17.1 | 30.8 | <0.001 |
| Current drinker, % | 29.0 | 37.0 | 29.9 | 35.8 | 0.007 |
| High mental stress, % | 17.7 | 17.3 | 18.4 | 23.0 | <0.001 |
| College or higher education, % | 9.7 | 10.6 | 9.2 | 11.7 | 0.08 |
| Unemployed, % | 13.9 | 11.0 | 11.6 | 11.6 | 0.09 |
| Walking≥30 min/d, % | 42.8 | 44.1 | 45.0 | 47.4 | 0.006 |
| Exercise≥1 h/wk, % | 21.5 | 26.5 | 25.5 | 25.1 | 0.10 |
| Vegetable intake, times/wk | 15.8 | 15.0 | 14.9 | 14.4 | <0.001 |
| Fish intake, times/wk | 7.4 | 7.0 | 7.1 | 6.7 | <0.001 |
| Fruits intake, times/wk | 6.8 | 6.7 | 7.2 | 6.9 | 0.21 |
| Soybeans intake, times/wk | 5.2 | 5.0 | 4.9 | 4.8 | <0.001 |
| High‐normal | |||||
| No. of participants | 1371 | 1423 | 521 | 532 | |
| Age, y | 59.4 | 56.6 | 55.4 | 52.4 | <0.001 |
| Sex, male, % | 34.2 | 40.8 | 32.3 | 42.2 | 0.02 |
| Systolic blood pressure, mm Hg | 132.2 | 132.5 | 132.0 | 131.8 | 0.02 |
| Diastolic blood pressure, mm Hg | 78.5 | 78.8 | 79.1 | 78.7 | 0.68 |
| Total cholesterol, mg/dL | 196.5 | 198.8 | 201.7 | 201.4 | 0.01 |
| Body mass index, kg/m2 | 23.1 | 23.1 | 23.2 | 23.1 | 0.89 |
| Antihypertensive medication, % | 10.7 | 7.3 | 10.5 | 10.1 | 0.71 |
| History of diabetes, % | 3.4 | 3.6 | 2.2 | 3.3 | 0.74 |
| Current smoker, % | 17.4 | 21.3 | 18.9 | 33.6 | <0.001 |
| Current drinker, % | 36.5 | 40.3 | 37.7 | 40.6 | 0.25 |
| High mental stress, % | 14.2 | 13.6 | 13.0 | 19.7 | 0.002 |
| College or higher education, % | 7.1 | 11.4 | 9.9 | 11.5 | 0.03 |
| Unemployed, % | 18.5 | 14.7 | 14.9 | 16.9 | 0.68 |
| Walking ≥30 min/d, % | 40.2 | 42.6 | 48.4 | 46.3 | 0.02 |
| Exercise ≥1 h/wk, % | 23.7 | 27.4 | 26.5 | 26.0 | 0.55 |
| Vegetable intake, times/wk | 16.1 | 15.3 | 14.9 | 14.0 | <0.001 |
| Fish intake, times/wk | 7.0 | 7.3 | 6.8 | 6.9 | 0.38 |
| Fruits intake, times/wk | 6.7 | 7.0 | 7.0 | 6.6 | 0.46 |
| Soybeans intake, times/wk | 5.1 | 5.3 | 5.2 | 4.8 | 0.03 |
| Grade 1 hypertension | |||||
| No. of participants | 1776 | 1709 | 577 | 570 | |
| Age, y | 60.5 | 57.9 | 57.1 | 55.0 | <0.001 |
| Sex, male, % | 39.8 | 41.3 | 34.8 | 43.0 | 0.36 |
| Systolic blood pressure, mm Hg | 144.4 | 143.8 | 144.8 | 143.6 | 0.10 |
| Diastolic blood pressure, mm Hg | 85.4 | 85.3 | 85.3 | 85.8 | 0.26 |
| Total cholesterol, mg/dL | 199.0 | 199.4 | 206.0 | 202.4 | 0.02 |
| Body mass index, kg/m2 | 23.7 | 23.6 | 23.8 | 23.5 | 0.25 |
| Antihypertensive medication, % | 22.4 | 20.9 | 16.1 | 16.9 | 0.00 |
| History of diabetes, % | 5.0 | 3.6 | 1.8 | 3.1 | 0.06 |
| Current smoker, % | 20.7 | 21.5 | 20.7 | 29.2 | <0.001 |
| Current drinker, % | 40.4 | 43.4 | 38.9 | 44.2 | 0.27 |
| High mental stress, % | 14.4 | 15.9 | 13.8 | 20.3 | 0.003 |
| College or higher education, % | 6.9 | 8.2 | 13.3 | 9.7 | 0.02 |
| Unemployed, % | 19.6 | 17.6 | 17.1 | 17.3 | 0.26 |
| Walking≥30 min/d, % | 45.3 | 45.3 | 45.4 | 46.7 | 0.56 |
| Exercise≥1 h/wk, % | 24.6 | 28.9 | 23.8 | 25.9 | 0.94 |
| Vegetable intake, times/wk | 15.4 | 15.3 | 15.5 | 14.9 | 0.25 |
| Fish intake, times/wk | 7.1 | 7.2 | 7.1 | 6.5 | 0.003 |
| Fruits intake, times/wk | 6.4 | 6.7 | 7.2 | 6.7 | 0.23 |
| Soybeans intake, times/wk | 5.0 | 5.2 | 5.2 | 5.0 | 0.53 |
| Grade 2–3 hypertension | |||||
| No. of participants | 753 | 633 | 222 | 200 | |
| Age, y | 61.8 | 59.7 | 58.6 | 56.9 | <0.001 |
| Sex, male, % | 44.4 | 43.2 | 33.9 | 40.2 | 0.21 |
| Systolic blood pressure, mm Hg | 167.2 | 165.7 | 167.5 | 164.0 | 0.01 |
| Diastolic blood pressure, mm Hg | 94.6 | 94.6 | 94.3 | 96.8 | 0.007 |
| Total cholesterol, mg/dL | 202.1 | 202.6 | 203.9 | 212.3 | 0.001 |
| Body mass index, kg/m2 | 24.2 | 24.1 | 24.2 | 24.2 | 0.93 |
| Antihypertensive medication, % | 38.2 | 33.7 | 32.8 | 31.7 | 0.14 |
| History of diabetes, % | 5.9 | 4.4 | 5.9 | 2.4 | 0.09 |
| Current smoker, % | 22.1 | 21.4 | 19.7 | 27.6 | 0.10 |
| Current drinker, % | 44.4 | 42.2 | 37.7 | 42.2 | 0.58 |
| High mental stress, % | 16.0 | 17.1 | 14.3 | 14.3 | 0.44 |
| College or higher education, % | 5.2 | 8.6 | 6.2 | 11.7 | 0.009 |
| Unemployed, % | 21.0 | 18.7 | 20.1 | 18.1 | 0.46 |
| Walking≥30 min/d, % | 48.5 | 47.4 | 56.9 | 54.9 | 0.05 |
| Exercise≥1 h/wk, % | 27.0 | 35.9 | 28.5 | 25.4 | 0.22 |
| Vegetable intake, times/wk | 15.4 | 14.6 | 15.5 | 13.4 | 0.01 |
| Fish intake, times/wk | 6.7 | 6.9 | 6.8 | 6.4 | 0.38 |
| Fruits intake, times/wk | 6.9 | 7.1 | 7.1 | 6.5 | 0.26 |
| Soybeans intake, times/wk | 5.0 | 4.9 | 5.1 | 4.9 | 0.83 |
Data are mean for continuous variables and percentages for categorical variables.
Age‐adjusted baseline characteristics of the participants by green tea consumption in each BP category are presented in Table 2. People with more frequent green tea consumption were more likely to be older and less likely to be unemployed, be smokers, or eat fruits regardless of BP categories. Among people with grade 2–3 hypertension, frequent green tea consumption was associated with a lower total cholesterol level.
Table 2.
Age‐Adjusted Baseline Characteristics of Participants by Green Tea Consumption in Each Blood Pressure Category
| Green tea consumption | P for trend | ||||||
|---|---|---|---|---|---|---|---|
| Blood pressure category | None | <1 cup/d | 1–2 cups/d | 3–4 cups/d | 5–6 cups/d | ≥7 cups/d | |
| Optimal and normal | |||||||
| No. of participants | 679 | 994 | 1020 | 2024 | 2245 | 1360 | |
| Age, y | 53.9 | 52.5 | 52.4 | 53.8 | 54.2 | 55.2 | <0.001 |
| Sex, male, % | 25.6 | 28.8 | 33.5 | 27.1 | 30.5 | 34.9 | <0.001 |
| Systolic blood pressure, mm Hg | 114.7 | 115.1 | 115.2 | 115.0 | 115.4 | 115.9 | 0.002 |
| Diastolic blood pressure, mm Hg | 71.0 | 71.1 | 71.1 | 70.8 | 71.1 | 71.3 | 0.51 |
| Total cholesterol, mg/dL | 196.5 | 192.4 | 193.3 | 193.8 | 194.4 | 191.2 | 0.08 |
| Body mass index, kg/m2 | 22.7 | 22.7 | 22.3 | 22.3 | 22.4 | 22.4 | 0.03 |
| Antihypertensive medication, % | 3.5 | 5.1 | 2.6 | 4.2 | 2.7 | 3.0 | 0.07 |
| History of diabetes, % | 2.5 | 1.5 | 2.1 | 2.2 | 2.2 | 2.6 | 0.41 |
| Current smoker, % | 16.0 | 18.3 | 22.8 | 16.2 | 19.4 | 24.5 | <0.001 |
| Current drinker, % | 25.0 | 37.9 | 37.3 | 30.9 | 33.0 | 35.6 | 0.12 |
| High mental stress, % | 21.0 | 16.6 | 21.4 | 17.8 | 18.6 | 17.9 | 0.21 |
| College or higher education, % | 8.8 | 10.0 | 10.7 | 10.9 | 10.2 | 10.4 | 0.38 |
| Unemployed, % | 14.6 | 14.8 | 11.7 | 11.7 | 11.8 | 10.1 | <0.001 |
| Walking≥30 min/d, % | 41.2 | 42.9 | 44.5 | 46.2 | 46.5 | 41.1 | 0.51 |
| Exercise≥1 h/wk, % | 22.0 | 23.6 | 26.0 | 25.6 | 24.9 | 23.6 | 0.49 |
| Vegetable intake, times/wk | 15.7 | 14.5 | 14.9 | 15.2 | 14.8 | 15.8 | 0.14 |
| Fish intake, times/wk | 7.2 | 6.8 | 7.1 | 7.0 | 7.1 | 7.5 | 0.03 |
| Fruits intake, times/wk | 6.6 | 5.8 | 6.7 | 7.1 | 7.0 | 7.2 | <0.001 |
| Soybeans intake, times/wk | 5.0 | 4.8 | 5.0 | 4.9 | 5.1 | 5.2 | 0.04 |
| High‐normal | |||||||
| No. of participants | 283 | 443 | 442 | 907 | 1106 | 666 | |
| Age, y | 56.3 | 54.8 | 55.4 | 56.6 | 57.8 | 58.3 | <0.001 |
| Sex, male, % | 28.4 | 36.9 | 39.6 | 34.1 | 38.0 | 44.2 | <0.001 |
| Systolic blood pressure, mm Hg | 131.9 | 132.1 | 131.9 | 132.2 | 132.4 | 132.6 | 0.003 |
| Diastolic blood pressure, mm Hg | 78.7 | 79.2 | 78.9 | 78.5 | 78.7 | 78.6 | 0.25 |
| Total cholesterol, mg/dL | 198.6 | 199.2 | 198.3 | 199.4 | 199.5 | 196.8 | 0.62 |
| Body mass index, kg/m2 | 23.3 | 23.3 | 23.2 | 22.9 | 23.1 | 23.2 | 0.28 |
| Antihypertensive medication, % | 10.8 | 11.8 | 9.6 | 8.7 | 7.9 | 10.3 | 0.18 |
| History of diabetes, % | 2.8 | 4.2 | 4.2 | 3.0 | 2.4 | 4.1 | 0.81 |
| Current smoker, % | 16.1 | 21.1 | 23.8 | 18.3 | 22.0 | 24.9 | 0.03 |
| Current drinker, % | 30.6 | 43.8 | 44.0 | 37.3 | 37.0 | 39.7 | 0.87 |
| High mental stress, % | 15.4 | 13.8 | 12.8 | 14.9 | 15.5 | 13.9 | 0.86 |
| College or higher education, % | 7.5 | 9.1 | 11.7 | 8.2 | 10.3 | 10.5 | 0.28 |
| Unemployed, % | 22.4 | 22.1 | 15.4 | 16.6 | 12.9 | 16.4 | <0.001 |
| Walking ≥30 min/d, % | 39.2 | 38.3 | 49.2 | 43.2 | 44.2 | 41.7 | 0.42 |
| Exercise ≥1 h/wk, % | 19.4 | 28.4 | 28.6 | 24.0 | 26.9 | 25.2 | 0.54 |
| Vegetable intake, times/wk | 14.8 | 14.6 | 15.1 | 15.2 | 15.6 | 15.8 | 0.01 |
| Fish intake, times/wk | 7.2 | 6.8 | 7.1 | 6.9 | 7.1 | 7.3 | 0.40 |
| Fruits intake, times/wk | 6.0 | 5.3 | 7.2 | 6.9 | 7.3 | 7.0 | <0.001 |
| Soybeans intake, times/wk | 5.2 | 4.9 | 5.2 | 5.1 | 5.3 | 5.2 | 0.39 |
| Grade 1 hypertension | |||||||
| No. of participants | 347 | 512 | 550 | 1044 | 1397 | 782 | |
| Age, y | 57.7 | 56.7 | 57.5 | 58.7 | 58.7 | 59.7 | <0.001 |
| Sex, male, % | 34.3 | 37.4 | 42.6 | 36.6 | 40.3 | 47.1 | <0.001 |
| Systolic blood pressure, mm Hg | 143.5 | 143.5 | 144.6 | 144.5 | 144.2 | 144.0 | 0.17 |
| Diastolic blood pressure, mm Hg | 85.4 | 86.1 | 85.7 | 85.3 | 85.1 | 85.3 | 0.08 |
| Total cholesterol, mg/dL | 198.4 | 204.9 | 200.1 | 200.7 | 200.8 | 197.9 | 0.16 |
| Body mass index, kg/m2 | 23.8 | 24.0 | 23.6 | 23.7 | 23.5 | 23.5 | 0.02 |
| Antihypertensive medication, % | 24.8 | 23.0 | 18.2 | 20.8 | 19.1 | 19.9 | 0.04 |
| History of diabetes, % | 3.2 | 4.0 | 2.6 | 3.7 | 4.2 | 4.5 | 0.17 |
| Current smoker, % | 18.1 | 22.1 | 21.8 | 19.1 | 21.6 | 28.3 | 0.002 |
| Current drinker, % | 37.4 | 47.5 | 39.3 | 41.4 | 40.1 | 45.4 | 0.36 |
| High mental stress, % | 15.7 | 14.4 | 17.7 | 16.7 | 15.0 | 14.5 | 0.54 |
| College or higher education, % | 8.6 | 6.3 | 9.7 | 9.4 | 7.1 | 10.5 | 0.27 |
| Unemployed, % | 20.8 | 22.1 | 18.6 | 17.3 | 17.0 | 18.2 | 0.02 |
| Walking ≥30 min/d, % | 41.0 | 43.7 | 48.1 | 47.8 | 47.0 | 41.0 | 0.93 |
| Exercise ≥1 h/wk, % | 23.2 | 23.6 | 28.1 | 28.4 | 27.3 | 23.4 | 0.66 |
| Vegetable intake, times/wk | 14.9 | 15.3 | 14.6 | 15.2 | 15.2 | 16.3 | 0.005 |
| Fish intake, times/wk | 6.5 | 7.2 | 6.9 | 7.0 | 7.1 | 7.3 | 0.04 |
| Fruits intake, times/wk | 5.5 | 5.5 | 6.8 | 6.8 | 6.9 | 7.0 | <0.001 |
| Soybeans intake, times/wk | 4.6 | 5.2 | 5.0 | 5.0 | 5.2 | 5.3 | 0.01 |
| Grade 2–3 hypertension | |||||||
| No. of participants | 115 | 157 | 214 | 431 | 601 | 290 | |
| Age, y | 59.3 | 57.3 | 60.3 | 60.1 | 60.6 | 61.0 | <0.001 |
| Sex, male, % | 32.3 | 43.0 | 49.0 | 39.9 | 40.2 | 48.2 | 0.11 |
| Systolic blood pressure, mm Hg | 166.3 | 163.1 | 165.1 | 167.0 | 167.4 | 166.1 | 0.05 |
| Diastolic blood pressure, mm Hg | 95.8 | 94.1 | 94.7 | 95.0 | 94.9 | 94.3 | 0.55 |
| Total cholesterol, mg/dL | 212.2 | 204.4 | 200.0 | 204.5 | 204.2 | 200.5 | 0.06 |
| Body mass index, kg/m2 | 24.4 | 24.2 | 24.0 | 24.0 | 24.2 | 24.1 | 0.68 |
| Antihypertensive medication, % | 42.4 | 32.4 | 35.2 | 32.8 | 36.1 | 36.1 | 0.65 |
| History of diabetes, % | 5.8 | 7.2 | 3.9 | 5.2 | 5.5 | 3.1 | 0.21 |
| Current smoker, % | 13.6 | 19.9 | 19.5 | 21.7 | 21.3 | 31.1 | <0.001 |
| Current drinker, % | 38.4 | 51.2 | 47.1 | 39.0 | 41.7 | 43.2 | 0.46 |
| High mental stress, % | 19.1 | 11.8 | 17.6 | 14.7 | 17.2 | 15.2 | 0.90 |
| College or higher education, % | 6.4 | 4.7 | 8.2 | 9.0 | 6.8 | 6.7 | 0.69 |
| Unemployed, % | 24.3 | 25.9 | 17.0 | 23.6 | 17.5 | 16.0 | 0.009 |
| Walking ≥30 min/d, % | 50.3 | 42.9 | 54.1 | 51.9 | 49.6 | 47.6 | 0.96 |
| Exercise ≥1 h/wk, % | 24.2 | 26.6 | 34.1 | 32.8 | 29.8 | 28.2 | 0.51 |
| Vegetable intake, times/wk | 16.0 | 13.0 | 14.3 | 14.6 | 15.5 | 15.2 | 0.20 |
| Fish intake, times/wk | 6.9 | 6.5 | 6.8 | 6.6 | 6.9 | 6.7 | 0.97 |
| Fruits intake, times/wk | 6.1 | 5.3 | 6.6 | 6.9 | 7.5 | 7.2 | <0.001 |
| Soybeans intake, times/wk | 4.7 | 4.4 | 5.4 | 4.7 | 5.1 | 5.0 | 0.17 |
Data are mean for continuous variables and percentages for categorical variables.
Risk of Cardiovascular Disease Mortality According to Coffee Consumption
During the 18.9 years of median follow‐up, a total of 842 CVD deaths were documented. Among people with grade 2 to 3 hypertension, coffee consumption of ≥2 cups/day was associated with an increased risk of CVD mortality, compared with non‐drinkers (Table 3). Further adjustment for potential confounding factors did not materially change the association. The multivariable hazard ratios of CVD mortality among grade 2 to 3 hypertension were 0.98 (95% CI, 0.67–1.43) for <1 cup/day, 0.74 (95% CI, 0.37–1.46) for 1 cup/day, and 2.05 (95% CI, 1.17–3.59) for ≥2 cups/day compared with non‐drinkers (P for trend=0.09). No significant association between coffee consumption and CVD mortality was found among people with optimal and normal BP, high‐normal BP, or grade 1 hypertension. In the sensitivity analysis, multiple imputation to account for missing values did not change the associations materially (Table S1).
Table 3.
HRs (95% CIs) of Cardiovascular Disease Mortality by Coffee Consumption in Each Blood Pressure Category
| Coffee consumption | P for trend | ||||
|---|---|---|---|---|---|
| None | <1 cup/d | 1 cup/d | ≥2 cups/d | ||
| Optimal and normal | |||||
| Person‐years | 42 128 | 55 006 | 20 312 | 23 825 | |
| No. of cases | 99 | 78 | 21 | 30 | |
| Mortality rate (per 1000 person‐years) | 2.4 | 1.4 | 1.0 | 1.3 | |
| Age‐ and sex‐adjusted HR (95% CI) | Ref | 0.82 (0.61–1.10) | 0.76 (0.48–1.23) | 1.26 (0.83–1.90) | 0.51 |
| Multivariable HR (95% CI) | Ref | 0.83 (0.61–1.12) | 0.78 (0.48–1.28) | 1.19 (0.77–1.85) | 0.62 |
| High‐normal | |||||
| Person‐years | 22 953 | 24 297 | 8346 | 8389 | |
| No. of cases | 86 | 57 | 17 | 13 | |
| Mortality rate (per 1000 person‐years) | 3.7 | 2.3 | 2.0 | 1.5 | |
| Age‐ and sex‐adjusted HR (95% CI) | Ref | 0.73 (0.52–1.03) | 0.80 (0.47–1.35) | 0.84 (0.46–1.51) | 0.41 |
| Multivariable HR (95% CI) | Ref | 0.75 (0.52–1.07) | 0.84 (0.49–1.45) | 0.75 (0.40–1.40) | 0.33 |
| Grade 1 hypertension | |||||
| Person‐years | 28 693 | 28 337 | 9133 | 8644 | |
| No. of cases | 140 | 89 | 32 | 25 | |
| Mortality rate (per 1000 person‐years) | 4.9 | 3.1 | 3.5 | 2.9 | |
| Age‐ and sex‐adjusted HR (95% CI) | Ref | 0.82 (0.63–1.07) | 1.02 (0.69–1.49) | 1.05 (0.68–1.62) | 0.77 |
| Multivariable HR (95% CI) | Ref | 0.90 (0.68–1.19) | 1.16 (0.78–1.74) | 1.06 (0.68–1.66) | 0.57 |
| Grade 2–3 hypertension | |||||
| Person‐years | 11 602 | 9673 | 3047 | 2688 | |
| No. of cases | 77 | 49 | 10 | 19 | |
| Mortality rate (per 1000 person‐years) | 6.6 | 5.1 | 3.3 | 7.1 | |
| Age‐ and sex‐adjusted HR (95% CI) | Ref | 0.86 (0.60–1.23) | 0.71 (0.36–1.37) | 1.78 (1.07–2.97) | 0.16 |
| Multivariable HR (95% CI) | Ref | 0.98 (0.67–1.43) | 0.74 (0.37–1.46) | 2.05 (1.17–3.59) | 0.09 |
Multivariable HR: adjusted for age, sex, green tea consumption, use of antihypertensive medication, total cholesterol levels, history of diabetes, body mass index, smoking status, alcohol consumption, hours of exercise, hours of walking, perceived mental stress, educational level, regular employment, and dietary intakes of vegetable, fish, fruits and soybeans. HR indicates hazard ratio.
Risk of Cardiovascular Disease Mortality According to Green Tea Consumption
Green tea consumption was not associated with an increased risk of CVD mortality among grade 1 to 3 hypertension (Table 4). The 5 to 6 cups/day of green tea consumption among people with a high‐normal BP and 1 to 2 cups/day of green tea consumption among people with optimal or normal BP were associated with a borderline reduced risk of CVD mortality in age‐ and sex‐adjusted analyses. After the additional adjustment, the association was attenuated and no longer statistically significant. Similar associations were observed using multiple imputation to account for missing values (Table S2).
Table 4.
HRs (95% CIs) of Cardiovascular Disease Mortality by Green Tea Consumption in Each Blood Pressure Category
| Green tea consumption | P for trend | ||||||
|---|---|---|---|---|---|---|---|
| None | <1 cup/d | 1–2 cups/d | 3–4 cups/d | 5–6 cups/d | ≥7 cups/d | ||
| Optimal and normal | |||||||
| Person‐years | 11 844 | 17 595 | 17 077 | 33 611 | 37 803 | 23 341 | |
| No. of cases | 28 | 22 | 17 | 54 | 69 | 38 | |
| Mortality rate (per 1000 person‐years) | 2.4 | 1.3 | 1.0 | 1.6 | 1.8 | 1.6 | |
| Age‐ and sex‐adjusted HR (95% CI) | Ref | 0.67 (0.38–1.17) | 0.53 (0.29–0.97) | 0.75 (0.47–1.18) | 0.89 (0.57–1.38) | 0.65 (0.40–1.07) | 0.97 |
| Multivariable HR (95% CI) | Ref | 0.69 (0.39–1.22) | 0.56 (0.30–1.04) | 0.81 (0.51–1.30) | 0.91 (0.58–1.43) | 0.67 (0.40–1.10) | 0.96 |
| High‐normal | |||||||
| Person‐years | 4841 | 7809 | 7069 | 14 938 | 18 147 | 11 181 | |
| No. of cases | 18 | 22 | 18 | 41 | 41 | 33 | |
| Mortality rate (per 1000 person‐years) | 3.7 | 2.8 | 2.5 | 2.7 | 2.3 | 3.0 | |
| Age‐ and sex‐adjusted HR (95% CI) | Ref | 0.85 (0.46–1.59) | 0.82 (0.42–1.57) | 0.80 (0.46–1.40) | 0.56 (0.32–0.98) | 0.65 (0.37–1.16) | 0.04 |
| Multivariable HR (95% CI) | Ref | 0.88 (0.46–1.69) | 0.92 (0.46–1.83) | 0.94 (0.53–1.68) | 0.62 (0.34–1.10) | 0.69 (0.38–1.27) | 0.06 |
| Grade 1 hypertension | |||||||
| Person‐years | 5819 | 8768 | 8617 | 16 541 | 22 233 | 12 828 | |
| No. of cases | 23 | 35 | 32 | 64 | 70 | 62 | |
| Mortality rate (per 1000 person‐years) | 4.0 | 4.0 | 3.7 | 3.9 | 3.1 | 4.8 | |
| Age‐ and sex‐adjusted HR (95% CI) | Ref | 1.06 (0.63–1.80) | 0.92 (0.54–1.57) | 0.89 (0.55–1.44) | 0.71 (0.45–1.14) | 0.95 (0.59–1.53) | 0.24 |
| Multivariable HR (95% CI) | Ref | 0.94 (0.55–1.60) | 0.94 (0.54–1.63) | 0.90 (0.55–1.47) | 0.71 (0.43–1.15) | 0.99 (0.60–1.63) | 0.47 |
| Grade 2–3 hypertension | |||||||
| Person‐years | 1738 | 2619 | 3098 | 5997 | 8985 | 4573 | |
| No. of cases | 11 | 11 | 14 | 42 | 50 | 27 | |
| Mortality rate (per 1000 person‐years) | 6.3 | 4.2 | 4.5 | 7.0 | 5.6 | 5.9 | |
| Age‐ and sex‐adjusted HR (95% CI) | Ref | 0.56 (0.24–1.30) | 0.53 (0.24–1.17) | 0.97 (0.50–1.88) | 0.68 (0.36–1.32) | 0.65 (0.32–1.33) | 0.83 |
| Multivariable HR (95% CI) | Ref | 0.49 (0.20–1.19) | 0.62 (0.26–1.43) | 1.03 (0.50–2.10) | 0.75 (0.37–1.54) | 0.65 (0.30–1.39) | 1.00 |
Multivariable HR: adjusted for age, sex, coffee consumption, use of antihypertensive medication, total cholesterol levels, history of diabetes, body mass index, smoking status, alcohol consumption, hours of exercise, hours of walking, perceived mental stress, educational level, regular employment, and dietary intakes of vegetable, fish, fruits and soybeans. HR indicates hazard ratio.
DISCUSSION
In a large prospective observational study of Japanese men and women aged 40 to 79 years with a median follow‐up of 18.9 years, heavy coffee drinking (≥2 cups/day) was associated with twice the CVD mortality of no coffee drinking among those with grade 2 to 3 hypertension (SBP ≥160 or DBP ≥100), while such an association was not observed for other BP categories. In contrast, green tea consumption was not associated with an increased risk of CVD mortality across any BP category. Our results suggest that heavy coffee consumption can increase the risk of CVD mortality among people with severe hypertension, while green tea consumption does not increase the risk of CVD mortality.
To the best of our knowledge, this is the first study to find a positive association between heavy coffee consumption and CVD mortality among people with severe hypertension. In the Framingham study of 1354 participants aged ≥65 years with 10.1 years of follow‐up, habitual caffeinated coffee consumption (≥1.0 versus 0 cups per day) was associated with a reduced risk of coronary heart disease mortality among persons with a BP less than stage 2 hypertension (SBP <160 mm Hg and diastolic BP <100 mm Hg) but not among those with stage 2 hypertension (SBP ≥160 mm Hg and DBP ≥100 mm Hg); the multivariable hazard ratio was 0.57 (95% CI, 0.36–0.91) and 0.87 (95% CI, 0.44–1.72), respectively. 11 In the Nurses' Health Study of 83 076 women with 24 years of follow‐up, no association between habitual coffee consumption and the risk of incident stroke was observed among participants with hypertension; the relative risks of stroke across the categories of coffee consumption (<1 cup per month, 1 per month to 4 per week, 5–7 per week, 2–3 per day, and ≥4 per day) were 1.0, 0.97 (95% CI, 0.76–1.24), 0.90 (95% CI, 0.72–1.11), 0.98 (95% CI, 0.77–1.24), and 1.10 (95% CI, 0.76–1.58). 15 That study is the largest observational study to date with comprehensive adjustment for confounders, but the risks among people with severe hypertension were not investigated.
Caffeinated coffee, which contains ingredients such as chlorogenic acid and other phenolic compounds, magnesium, and trigonelline, has been shown to lower serum cholesterol levels, improve endothelial function, and reduce inflammation in women with diabetes. 16 , 17 Habitual coffee drinkers can also develop caffeine tolerance, which may reduce the adverse effects of caffeine on CVD outcomes. 18 The harmful cardiovascular effects of caffeine (ie, transient BP elevation) would be offset by the beneficial effects of these other components and tolerance to caffeine in the general population. However, because people with hypertension are more susceptible to the effects of caffeine, 6 caffeine's harmful effects may outweigh its protective effects and increase the risk of mortality in people with severe hypertension.
In contrast, the mechanism underlying the beneficial effects of green tea may be explained by the effect of (−)‐epigallocatechin3‐gallate, the most abundant polyphenol in green tea. Previous animal studies have suggested that (−)‐epigallocatechin3‐gallate can significantly reduce BP levels and enhance endothelial function in hypertensive rats. 19 , 20 , 21 (−)‐epigallocatechin3‐gallate can also reduce oxidative stress, 22 attenuate inflammation, 23 , 24 and improve the plasma lipid profile. 25 These beneficial effects of green tea catechins may partially explain why only coffee consumption was associated with an increased risk of mortality in people with severe hypertension despite both green tea and coffee containing caffeine.
The strength of the present study is its prospective design that minimizes recall bias of the exposure assessment and the sufficient number of CVD deaths among people with severe hypertension to enable the assessment of the impact of coffee and green tea consumption. Furthermore, we were able to examine the risk of a high consumption of green tea compared with studies in Western countries. However, this study also has several limitations. First, because the consumption of coffee or green tea was self‐reported, false reporting could be a potential problem. Second, since there was only a single baseline assessment of BP and coffee and green tea consumption, we did not take into account for BP and the consumption changes during the follow‐up. Nondifferential misclassification could result in underestimation of the association between coffee or green tea consumption and mortality outcomes across BP categories. However, a relatively high correlation coefficient of coffee (Spearman's correlation coefficient, 0.86) and green tea (Spearman's correlation coefficient, 0.62) consumption was observed at 1 year apart in the validation study. 14 Third, we cannot rule out confounding attributable to unmeasured factors or residual confounding despite our efforts to adjust for many potential confounding factors. Finally, the causality of coffee consumption in relation to CVD risk among people with hypertension cannot be determined because of the observational nature of this study.
Heavy coffee consumption was associated with an increased risk of CVD mortality among people with severe hypertension but not in those without hypertension or with grade 1 hypertension. In contrast, green tea consumption was not associated with an increased risk of CVD mortality across all BP categories. The present study may support the assertion that heavy coffee consumption should be avoided among people with severe hypertension. More research is needed to confirm the effects of coffee and green tea consumption among people with hypertension.
Sources of Funding
The JACC was supported by Grants‐in‐Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan (Monbusho); Grants‐in‐Aid for Scientific Research on Priority Areas of Cancer; and Grants‐in‐Aid for Scientific Research on Priority Areas of Cancer Epidemiology from the Ministry of Education, Culture, Sports, Science and Technology of Japan (MonbuKagaku‐sho) (Nos. 61010076, 62010074, 63010074, 1010068, 2151065, 3151064, 4151063, 5151069, 6279102, 11181101, 17015022, 18014011, 20014026, 20390156, and 26293138); grant‐in‐aid from the Ministry of Health, Labor and Welfare, Health and Labor Sciences research grants, Japan (Research on Health Services: H17‐Kenkou‐007; Comprehensive Research on Cardiovascular Disease and Life‐Related Disease: H18‐Junkankitou [Seishuu]‐Ippan‐012; H19‐Junkankitou [Seishuu]‐Ippan‐012; H20‐Junkankitou [Seishuu]‐Ippan‐013; H23‐Junkankitou [Seishuu]‐Ippan‐005; H26‐Junkankitou [Seisaku]‐Ippan‐001; H29‐Junkankitou‐Ippan‐003; 20FA1002); National Cancer Center Research and Development Fund (27‐A‐4, 30‐A‐15, 2021‐A‐16); and Japan Society for the Promotion of Science KAKENHI Grant Number JP16H06277 and JP25330039.
Disclosures
None.
Supporting information
Tables S1–S2
Acknowledgments
We thank all staff members involved in this study for their valuable help in conducting the baseline survey and follow‐up.
Supplemental Material is available at https://www.ahajournals.org/doi/suppl/10.1161/JAHA.122.026477
For Sources of Funding and Disclosures, see page 11.
References
- 1. Chei CL, Loh JK, Soh A, Yuan JM, Koh WP. Coffee, tea, caffeine, and risk of hypertension: the Singapore Chinese Health Study. Eur J Nutr. 2018;57:1333–1342. doi: 10.1007/s00394-017-1412-4 [DOI] [PubMed] [Google Scholar]
- 2. Freedman ND, Park Y, Abnet CC, Hollenbeck AR, Sinha R. Association of coffee drinking with total and cause‐specific mortality [published correction appears in N Engl J Med. 2012 Jul 19;367(3):285]. N Engl J Med. 2012;366:1891–1904. doi: 10.1056/NEJMoa1112010 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 3. Ding M, Bhupathiraju SN, Satija A, van Dam RM, Hu FB. Long‐term coffee consumption and risk of cardiovascular disease: a systematic review and a dose‐response meta‐analysis of prospective cohort studies. Circulation. 2014;129:643–659. doi: 10.1161/CIRCULATIONAHA.113.005925 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 4. Kim Y, Je Y, Giovannucci E. Coffee consumption and all‐cause and cause‐specific mortality: a meta‐analysis by potential modifiers. Eur J Epidemiol. 2019;34:731–752. doi: 10.1007/s10654-019-00524-3 [DOI] [PubMed] [Google Scholar]
- 5. Mesas AE, Leon‐Muñoz LM, Rodriguez‐Artalejo F, Lopez‐Garcia E. The effect of coffee on blood pressure and cardiovascular disease in hypertensive individuals: a systematic review and meta‐analysis. Am J Clin Nutr. 2011;94:1113–1126. doi: 10.3945/ajcn.111.016667 [DOI] [PubMed] [Google Scholar]
- 6. Hartley TR, Sung BH, Pincomb GA, Whitsett TL, Wilson MF, Lovallo WR. Hypertension risk status and effect of caffeine on blood pressure. Hypertension. 2000;36:137–141. doi: 10.1161/01.HYP.36.1.137 [DOI] [PubMed] [Google Scholar]
- 7. Mostofsky E, Schlaug G, Mukamal KJ, Rosamond WD, Mittleman MA. Coffee and acute ischemic stroke onset: the Stroke Onset Study. Neurology. 2010;75:1583–1588. doi: 10.1212/WNL.0b013e3181fb443d [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8. Peng X, Zhou R, Wang B, Yu X, Yang X, Liu K, Mi M. Effect of green tea consumption on blood pressure: a meta‐analysis of 13 randomized controlled trials. Sci Rep. 2014;4:6251. doi: 10.1038/srep06251 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 9. Teramoto M, Muraki I, Yamagishi K, Tamakoshi A, Iso H. Green tea and coffee consumption and all‐cause mortality among persons with and without stroke or myocardial infarction. Stroke. 2021;52:957–965. doi: 10.1161/STROKEAHA.120.032273 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 10. Abe SK, Saito E, Sawada N, Tsugane S, Ito H, Lin Y, Tamakoshi A, Sado J, Kitamura Y, Sugawara Y, et al. Green tea consumption and mortality in Japanese men and women: a pooled analysis of eight population‐based cohort studies in Japan. Eur J Epidemiol. 2019;34:917–926. doi: 10.1007/s10654-019-00545-y [DOI] [PubMed] [Google Scholar]
- 11. Greenberg JA, Chow G, Ziegelstein RC. Caffeinated coffee consumption, cardiovascular disease, and heart valve disease in the elderly (from the Framingham Study). Am J Cardiol. 2008;102:1502–1508. doi: 10.1016/j.amjcard.2008.07.046 [DOI] [PubMed] [Google Scholar]
- 12. Tamakoshi A, Ozasa K, Fujino Y, Suzuki K, Sakata K, Mori M, Kikuchi S, Iso H, JACC Study Group , Sakauchi F, et al. Cohort profile of the Japan Collaborative Cohort Study at final follow‐up. J Epidemiol. 2013;23:227–232. doi: 10.2188/jea.JE20120161 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 13. Williams B, Mancia G, Spiering W, Agabiti Rosei E, Azizi M, Burnier M, Clement DL, Coca A, de Simone G, Dominiczak A, et al. 2018 ESC/ESH Guidelines for the management of arterial hypertension: the Task Force for the management of arterial hypertension of the European Society of Cardiology and the European Society of Hypertension: the Task Force for the management of arterial hypertension of the European Society of Cardiology and the European Society of Hypertension [published correction appears in J Hypertens. 2019 Jan;37:226]. J Hypertens. 2018;36:1953–2041. doi: 10.1097/HJH.0000000000001940 [DOI] [PubMed] [Google Scholar]
- 14. Date C, Fukui M, Yamamoto A, Wakai K, Ozeki A, Motohashi Y, Adachi C, Okamoto N, Kurosawa M, Tokudome Y, et al. Reproducibility and validity of a self‐administered food frequency questionnaire used in the JACC study. J Epidemiol. 2005;15:S9–S23. doi: 10.2188/jea.15.S9 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 15. Lopez‐Garcia E, Rodriguez‐Artalejo F, Rexrode KM, Logroscino G, Hu FB, van Dam RM. Coffee consumption and risk of stroke in women. Circulation. 2009;119:1116–1123. doi: 10.1161/CIRCULATIONAHA.108.826164 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 16. Lopez‐Garcia E, van Dam RM, Qi L, Hu FB. Coffee consumption and markers of inflammation and endothelial dysfunction in healthy and diabetic women. Am J Clin Nutr. 2006;84:888–893. doi: 10.1093/ajcn/84.4.888 [DOI] [PubMed] [Google Scholar]
- 17. Williams CJ, Fargnoli JL, Hwang JJ, van Dam RM, Blackburn GL, Hu FB, Mantzoros CS. Coffee consumption is associated with higher plasma adiponectin concentrations in women with or without type 2 diabetes: a prospective cohort study. Diabetes Care. 2008;31:504–507. doi: 10.2337/dc07-1952 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 18. Geleijnse JM. Habitual coffee consumption and blood pressure: an epidemiological perspective. Vasc Health Risk Manag. 2008;4:963–970. doi: 10.2147/VHRM.S3055 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 19. Ikeda M, Suzuki C, Umegaki K, Saito K, Tabuchi M, Tomita T. Preventive effects of green tea catechins on spontaneous stroke in rats. Med Sci Monit. 2007;13:BR40–BR45. [PubMed] [Google Scholar]
- 20. Potenza MA, Marasciulo FL, Tarquinio M, Tiravanti E, Colantuono G, Federici A, Kim JA, Quon MJ, Montagnani M. EGCG, a green tea polyphenol, improves endothelial function and insulin sensitivity, reduces blood pressure, and protects against myocardial I/R injury in SHR. Am J Physiol Endocrinol Metab. 2007;292:E1378–E1387. doi: 10.1152/ajpendo.00698.2006 [DOI] [PubMed] [Google Scholar]
- 21. Negishi H, Xu JW, Ikeda K, Njelekela M, Nara Y, Yamori Y. Black and green tea polyphenols attenuate blood pressure increases in stroke‐prone spontaneously hypertensive rats. J Nutr. 2004;134:38–42. doi: 10.1093/jn/134.1.38 [DOI] [PubMed] [Google Scholar]
- 22. Frei B, Higdon JV. Antioxidant activity of tea polyphenols in vivo: evidence from animal studies. J Nutr. 2003;133:3275S–3284S. doi: 10.1093/jn/133.10.3275S [DOI] [PubMed] [Google Scholar]
- 23. Zhao J, Liu J, Pang X, Zhang X, Wang S, Wu D. Epigallocatechin‐3‐gallate inhibits angiotensin II‐induced C‐reactive protein generation through interfering with the AT1‐ROS‐ERK1/2 signaling pathway in hepatocytes. Naunyn Schmiedebergs Arch Pharmacol. 2016;389:1225–1234. doi: 10.1007/s00210-016-1279-6 [DOI] [PubMed] [Google Scholar]
- 24. Wang T, Xiang Z, Wang Y, Li X, Fang C, Song S, Li C, Yu H, Wang H, Yan L, et al. (−)‐Epigallocatechin gallate targets notch to attenuate the inflammatory response in the immediate early stage in human macrophages. Front Immunol. 2017;8:433. doi: 10.3389/fimmu.2017.00433 [DOI] [PMC free article] [PubMed] [Google Scholar]
- 25. Koo SI, Noh SK. Green tea as inhibitor of the intestinal absorption of lipids: potential mechanism for its lipid‐lowering effect. J Nutr Biochem. 2007;18:179–183. doi: 10.1016/j.jnutbio.2006.12.005 [DOI] [PMC free article] [PubMed] [Google Scholar]
Associated Data
This section collects any data citations, data availability statements, or supplementary materials included in this article.
Supplementary Materials
Tables S1–S2