The effects of age, gender, obesity, health habits, and vegetable consumption frequency on hypertension in elderly Chinese Americans

Nutrition Research 25 (2005) 31 – 43 www.elsevier.com/locate/nutres

The effects of age, gender, obesity, health habits, and vegetable consumption frequency on hypertension in elderly Chinese Americans Chick F. Tama,*, Lan Nguyena, Susan S. Pea, Karine Hajyana, Sareen Kevorka, Rebecca Davisb, George Poonc, Polong Lewc a

Department of Kinesiology and Nutritional Science, College of Health and Human Services, 5151 State University Drive, Los Angeles, CA 90032, USA b Department of Art, School of Arts and Letters, California State University, Los Angeles, CA 90032, USA c Chinatown Senior Citizen Service Center, Los Angeles, CA 90032, USA Received 3 November 2003; revised 15 December 2003; accepted 12 March 2004

Abstract The purpose of this study was to assess the effects of age, gender, obesity, consumption frequency of selected vegetables, alcohol consumption, cigarette smoking, and tea consumption on the prevalence rate (PR) of hypertension in elderly Chinese Americans. Hypertension is defined as having a systolic blood pressure (SBP) and/or diastolic blood pressure (DBP) z140 mm Hg and z90 mm Hg, respectively. A total of 205 subjects were recruited in the Chinatown section of Los Angeles, CA. Hypertension was more prevalent in the oldest age groups for both sexes (45.1%), and the percentage of hypertension for men was lower than those of female counterparts (47% vs. 53%, respectively). The percentage of lean (body mass index [BMI] b 25 kg/m2) hypertensive subjects was higher than those of obese (BMI N 27 kg/m2) hypertensive subjects in group 1 (50-64 years), group 2 (65-74 years), and group 3 (z75 years) (32%, 24%, and 26%; vs. 3%, 11%, and 13%, respectively). The overall percentage of obese hypertensive subjects was higher in women than those of their male counterparts (13% vs. 6%, respectively) and increased substantially with age as well. In conclusion, age and gender (particularly in lean men and obese women), were the greater risk factors for the development of hypertension. D 2005 Published by Elsevier Inc. Keywords: Elderly Chinese Americans; Hypertension; Vegetable consumption frequency; Alcohol consumption; Cigarette smoking; Tea consumption

* Corresponding author. Tel.: +1 323 343 4641; fax: +1 323 343 6482. E-mail address: [email protected] (C.F. Tam). 0271-5317/$ – see front matter D 2005 Published by Elsevier Inc. doi:10.1016/j.nutres.2004.03.004

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1. Introduction Epidemiological studies have demonstrated that arterial hypertension or high blood pressure is a significant risk factor for cardiovascular mortality and morbidity [1]. The number of hypertensive cases in the United States continues to rise due to improper diet, sedentary lifestyle, and the growing population of the elderly. According to Svetkey et al., approximately 43 million Americans have hypertension and 50% of adults aged z60 years have high blood pressure [2]. Furthermore, systolic hypertension adds to the risk of cardiovascular disease independently of any associated arteriosclerosis [3]. The two major types of hypertension most common in older persons are isolated systolic hypertension and combined systolic-diastolic hypertension [4]. Fortunately, the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) reported that dietary and lifestyle modifications have been shown to reduce arterial blood pressure, especially in patients with prehypertension (systolic blood pressure [SBP] 120-139 mm Hg and/or diastolic blood pressure [DBP] 80-89 mm Hg) or stage 1 hypertension (SBP 140-159 mm Hg and/or DBP 90-99 mm Hg) [5]. One nutritional antihypertensive therapy available to hypertensive patients is the Dietary Approaches to Stop Hypertension (DASH) diet. The rationale and efficacy of the DASH diet is attributed to its low total fat consumption and high fruits/vegetables intake. Studies have shown that high-quality nutrient dense foods such as fruits/vegetables contain various phytochemicals, vitamins, minerals, and fiber that are associated with healthy systolic and diastolic blood pressures [6]. However, it has been difficult to isolate the specific nutrients responsible for differences in the prevalence rate of hypertension among different age, gender, and ethnic groups. Even though dietary habits can have a direct effect on blood pressure, lifestyle choices such as alcohol intake, cigarette smoking, physical activity, and obesity can profoundly impact blood pressure regulation as well. The JNC 7 report has advised four lifestyle changes for reducing hypertension: weight loss, increased physical exercise, reduced alcohol intake, and reduced sodium consumption [7]. Despite increased advancement in the pathophysiology and detection of hypertension, not adhering to set nutritional dietary and lifestyle guidelines could result in the accumulation of other health complications such as juvenile/adult obesity, elevated plasma lipid levels, and advanced progression of atherosclerotic lesion formation [8]. Of the many known risk factors for hypertension, age, sex, ethnicity, and genetic predisposition cannot be altered. However, certain risk factors can be minimized, and it is essential to characterize the specific causes that can reduce the progression of this disease in various age groups and ethnic populations. The purpose of this study was to assess the following: 1) the prevalence of various classifications of hypertension according to the Chinese population’s three age groups and according to gender; 2) the influence of age, gender, and obesity on the prevalence rate of hypertension; and 3) the influence of vegetable consumption frequency, cigarette smoking, alcohol intake, and tea consumption on the prevalence rate of hypertension.

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2. Methods and materials 2.1. Subjects Moderately healthy elderly Chinese Americans residing in the Cathay Manor Senior Service Center in the Chinatown section of Los Angeles, CA, were involved in the study. This study was reviewed and approved by the Institutional Review Board on Human Subjects Committee at the California State University, Los Angeles. bModerately healthyQ was defined as being physically mobile with limitations due to the symptoms of chronic diseases such as hypertension. A total of 205 subjects (90 men and 115 women) between the ages of 53 and 90 years (mean age, 72.6 F 7.6 years) were assigned to one of three age groups: 1) group 1, young-old group (50-64 years); group 2, middle-old group (65-74 years), and group 3, oldold group (z75 years). A subgroup of 97 elderly Chinese Americans (47 men and 50 women) were randomly selected for assessment of health habits and vegetable consumption frequency. 2.2. Physiological measurements A resident physician measured blood pressures using a random-zero sphygmomanometer. Height was measured in feet and inches, and weight was measured in pounds. 2.3. Survey methods To assess the incidence rate of hypertension in elderly Chinese Americans, a survey questionnaire was distributed and filled out by the randomly selected subgroup of 97 participants. The survey questionnaire included self-reported demographic and lifestyle questions such as name, age, gender, vegetable consumption frequency, cigarette smoking, alcohol intake, and tea consumption. Vegetable consumption frequency was assessed by the frequency rate of never/rarely; once/week; 2-3 times/week; once/day; or z2 times/day. The assessed vegetables most frequently consumed in the Chinese diet included amaranth, Chinese and/or American broccoli, Chinese and/or American celery, Chinese greens, leek, lettuce, Pak-Coy and/or cabbage, and spinach. Subjects were asked to report the status of their past and current consumption of alcohol and cigarette smoking. The amount of alcohol consumption was surveyed in cups and reported in milliliters per day (236.6 mL = 1 cup). The alcohol consumption of subjects was categorized as light drinker (V13 mL of ethanol/day) or heavy drinker (N13 mL/day of ethanol/day). Cigarette smoking was reported as current smoker or ex-smoker and history of habitual smoking was stated in years. The amount of tea consumption was reported in cup(s)/day (1 cup = 6 ounces). 2.4. Data analyses Raw data were converted to uniform units such as centimeters for height and kilograms for weight. The Standard Quetelet Index was used to calculate body mass index (BMI). The cup unit was converted to milliliters. The numerical coding system was used to calculate the level of vegetable consumption frequency, with 0 representing the least frequency and 4 representing the most frequency rate. Subjects were categorized as lean with BMI b25 kg/m2 and as obese with BMI N27 kg/m2. Hypertension was defined as SBP z 140 and/or DBP z 90 mm Hg. The classification of hypertension was adapted from the published criteria [7].

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2.5. Statistical analyses The results were analysed using the SPSS statistical program (SPSS Inc., Chicago, IL). Descriptive statistics were performed for the generation of mean, standard deviation (SD) of the mean, frequency, percentage, prevalence rate (PR), independent-samples t test, and Pearson correlation coefficient. An a level of 0.05 was used as the standard for statistical significance. 3. Results This study included 205 elderly Chinese-American subjects. The average age was 72.4 F 7.6 years, ranging from 53 to 90 years (Table 1). There were 90 men (average age 72.7 F 6.6 years) and 115 women (average age 72.5 F 8.3 years). Their height, weight, and blood pressures (systolic and diastolic) were measured and recorded (Table 1). Both current and past alcohol intake, cigarette smoking, and tea consumption habits were collected from 97 subjects (47 men and 50 women). 3.1. Age differences in hypertension Age difference was statistically significant for all three age groups. There was statistical significance in diastolic blood pressures between groups 1 and 3 ( P = 0.019) and between groups 2 and 3 ( P = 0.006) (Table 1). For systolic blood pressures, a significant variation was

Table 1 Mean age, height, weight, BMI, and systolic/diastolic blood pressures of 205 elderly Chinese Americans subdivided into three age groups Total sample Sample size Age (yr.) Height (cm) Weight (kg) BMI (kg/m2) Blood pressure SBP DBP

Age groups Group 1 (50-64 yr.)

Group 2 (65-74 yr.)

Group 3 ( z 75 yr.)

205 72.4 F 7.6 157.6 F 9.7 60.2 F 9.8 24.3 F 3.5

31 61.0 F 2.8* 157.9 F 10.2 58.2 F 8.0 23.4 F 2.7

92 69.7 F 3.0y 158.7 F 10.7 61.9 F 9.7§ 24.7 F 3.7

82 79.8 F 4.2z 157.0 F 9.1 58.9 F 10.1 24.0 F 3.7

141.5 F 12.7 80.3 F 8.1

135.2 F 16.8b 82.2 F 8.5yy

140.9 F 12.5O 81.4 F 7.5zz

144.2 F 10.5** 78.2 F 7.5

Data were expressed as Mean F SD. * P = 0.000 between Group 1 and y P = 0.000 between Group 1 and z P = 0.000 between Group 2 and § P = 0.046 between Group 2 and b P = 0.050 between Group 1 and O P = 0.001 between Group 1 and ** P = 0.058 between Group 2 and yy P = 0.019 between Group 1 and zz P = 0.006 between Group 2 and

Group Group Group Group Group Group Group Group Group

2. 3. 3. 3. 2. 3. 3. 3. 3.

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Table 2 Mean percentage of the prevalence rate (PR) of systolic blood pressure (SBP N 140 mm Hg) and diastolic blood pressure (DBP N 90 mm Hg) hypertension in three age groups of the elderly Chinese Americans Age groups Group 1 (50-64 yr.) Group 2 (65-74 yr.) Group 3 (z75 yr.)

N 31 92 82

Systolic hypertension (z140 mmHg)

Diastolic hypertension (z90 mmHg)

N

Mean % PR

N

Mean % PR

11 36 36

35 40 44

4 30 20

13 33 24

found among the three age groups. The incidence rate of systolic hypertension progressively increased with age, whereas the incidence rate of diastolic hypertension gradually declined with age between groups 2 and 3 (Table 2). The percentage of hypertension was ~40% for all three age groups. The highest percentage of hypertension was borderline isolated systolic hypertension (BH) observed in group 3. The lowest percentage of hypertension was combined systolic–diastolic hypertension, and isolated systolic hypertension (ISH). There was no severe diastolic hypertension observed in this population (Fig. 1). The percentage of lean hypertensive subjects was highest in group 1 (age 50-64 years) and lowest in group 2 (age 65-74 years). Conversely, the percentage of obese hypertensive subjects progressively increased with increasing age (Table 3). 3.2. Gender differences in hypertension The average age of both women and men were similar in this population and the percentage of hypertension in both genders was N40%. The mean systolic blood pressure and diastolic blood pressure were not significantly different between genders. In general, the mean percentage of classification for various types of hypertension was higher in men than

Fig. 1. Mean percentage of classification for various types of hypertension in elderly Chinese Americans in study groups 1, 2, and 3.

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Table 3 Mean percentage of the prevalence rate (PR) of hypertensive and normotensive cases in lean and obese subjects for the three age groups and between genders Age group

N

Lean Hypertensive

Group 1 Group 2 Group 3 Gender Males Females

Obese Normotensive

Hypertensive

Normotensive

N

Mean % PR

N

Mean % PR

N

Mean % PR

N

Mean % PR

31 92 82

10 22 21

32 24 26

13 28 36

42 30 44

1 10 11

3 11 13

1 12 6

3 13 7

90 115

27 26

30 23

35 42

39 37

5 15

6 13

5 13

6 11

those in women with the exception of borderline isolated systolic hypertension (BH). Women had the highest percentage of BH in this population (Fig. 2). The percentage of diastolic hypertension (i.e., hypertension based on diastolic blood pressure), combined hypertension, isolated systolic hypertension (ISH), and mild diastolic hypertension (MDH) were higher in men than in women (Table 4). However, the percentage of systolic hypertension and borderline isolated systolic hypertension (BH) was higher in women than in men. There were no reported subjects with severe diastolic hypertension (Table 4).

Fig. 2. Mean percentage of classification for various types of hypertension in male and female elderly Chinese Americans.

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Table 4 Mean percent classification of various hypertensions in Groups 1-3 between male and female elderly Chinese Americans Classification of hypertension

Total N = 205

Hypertension Systolic hypertension Diastolic hypertension Combined hypertension Borderline isolated systolic hypertension Isolated systolic hypertension Mild diastolic hypertension Moderate diastolic hypertension

Men N = 90

Women N = 115

N

%

N

Mean %

N

Mean %

88 84 10 6 88 12 51 1

43.0 41.0 4.9 3.0 43.0 5.9 25.0 0.5

41 39 6 4 30 8 28 1

47 46 60 67 34 67 55 100

47 45 4 2 58 4 23 0

53 54 40 33 66 33 45 0

3.3. Differences in vegetable consumption frequency between hypertensive and normotensive subjects The most common vegetable consumption frequency patterns were 2-3 times/week and once/day for each specifically assessed vegetable. In contrast, z2 times/day was the least common consumption pattern (Table 5). According to data collected, Pak-Coy/cabbage was the most popular choice of vegetable to be consumed once daily for both hypertensive and normotensive subjects. However, more hypertensive individuals consumed Pak-Coy/cabbage once daily than those of their normotensive counterparts. Table 5 Mean percentage of vegetable consumption frequency in the hypertensive group (HG) and normotensive group (NG) in elderly Chinese Americans Vegetable

Group

N

Once/Week, % Mean

2-3 Times/Week, % Mean

Once/Day, % Mean

z2 Times/Day, % Mean

Amaranth

HG NG HG NG HG NG HG NG HG NG HG NG HG NG HG NG HG NG

40 57 40 57 40 57 40 57 40 57 40 57 40 57 40 57 40 57

7.5 3.5 0.0 1.8 2.5 1.8 15.0 14.0 0.0 1.8 0.0 0.0 2.5 7.0 7.5 0.0 35.0 29.9

2.5 1.8 20.0 8.8 2.5 3.5 17.5 33.3 0.0 0.0 0.0 1.8 15.0 19.3 5.0 5.3 62.5 73.8

0.0 0.0 0.0 10.5 0.0 1.8 35.0 14.0 0.0 0.0 2.5 3.5 60.0 43.9 2.5 1.8 100.0 75.5

0.0 0.0 0.0 1.8 0.0 0.0 2.5 8.8 0.0 0.0 0.0 0.0 5.0 1.8 0.0 0.0 7.5 12.4

Broccoli Celery Greens Leek Lettuce Pak-Coy Spinach Total

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Table 6 Comparisons of health habits in hypertensive and normotensive subjects in elderly Chinese Americans Characteristic

Hypertensive

Normotensive

Sample size % Alcohol drinker % Ex-drinker Alcohol consumption (mL of ethanol/day) Ex-alcohol consumption (mL of ethanol/day) % Cigarette smoker % Ex-smoker Smoking history (yr.) Tea consumption (cups/day)

40 5.0 12.5 11.9 47.4 10.0 32.5 10.0 0.7

57 3.5 17.5 7.1 27.1 3.5 29.8 5.6 0.8

Majority of the assessed vegetables were consumed once/week and 2-3 times/week in both groups. Comparisons between two groups’ consumption of all the assessed vegetables in each frequency category revealed that normotensive subjects (12.4%) consumed vegetables more frequently (i.e., z2 times per day) than did hypertensive subjects. However, the majority of hypertensive subjects (100.0%) consumed vegetables at least once per day. There were no substantial differences in a reduced consumption frequency category (Table 5). 3.4. Differences between health habits in hypertensive and normotensive subjects Using an independent-samples t test, assessment of differences in health habits in hypertensive versus normotensive individuals indicated that there was no statistical significance in any of the health habits assessed. However, there were more hypertensive individuals reported as being current cigarette smokers, and their respective smoking histories were almost twice as long as their normotensive counterparts (Table 6). There were no significant differences found in the amount of current alcohol consumption and previous alcohol consumption between both groups and current alcohol consumption was b13 mL of ethanol/day (light drinker). However, the former consumers of alcohol were reported as having consumed N13 mL/day of ethanol (heavy drinkers) for both hypertensive and normotensive subjects (Table 6). Table 7 Comparisons of health habits in hypertensive male and female subjects in elderly Chinese Americans Characteristic

Hypertensive Men

Hypertensive Women

Sample size % Alcohol drinker % Ex-drinker Alcohol consumption (mL of ethanol/day) Ex-alcohol consumption (mL of ethanol/day) % Cigarette smoker % Ex-smoker Smoking history (yr.) Tea consumption (cups/day)

24 8.3 20.8 22.5 73.5 16.7 54.2 16.6 0.70

16 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.34

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Table 8 Correlation coefficient of age, body mass index (BMI), and blood pressures to vegetable consumption frequency Vegetable Amaranth Broccoli Celery Greens Leek Lettuce Pak-Coy Spinach

Age

BMI

SBP

DBP

G*

P

G

P

G

P

G

P

0.19 0.13 0.17 0.02 0.09 0.00 0.07 0.08

0.069 0.192 0.107 0.871 0.395 0.998 0.482 0.428

0.00 0.03 0.06 0.04 0.12 0.04 0.06 0.05

0.977 0.805 0.581 0.729 0.246 0.720 0.577 0.623

0.05 0.03 0.10 0.02 0.08 0.05 0.19 0.03

0.601 0.805 0.345 0.832 0.465 0.612 0.061 0.755

0.14 0.04 0.01 0.08 0.01 0.06 0.03 0.10

0.182 0.667 0.938 0.466 0.935 0.566 0.786 0.337

DBP = diastolic blood pressure; SBP = systolic blood pressure. * Pearson correlation coefficient.

3.5. Differences between health habits in male and female hypertensive subjects It is worth noting that there were significant health habit differences in gender among hypertensive individuals. There is clear indication in Table 7 that female hypertensive subjects did not consume alcohol or smoke cigarettes, whereas significantly more male hypertensive subjects were reported to be drinkers and smokers. Also, significantly more male hypertensive subjects were reported as ex-smokers, and their smoking history was also considered significantly longer (mean, 16.6 years) than those of their female counterparts (Table 7). Among male hypertensive subjects, their current alcohol consumption (22.5 mL of ethanol/day) and former alcohol consumption (73.5 mL of ethanol/day) categorized them as being heavy drinkers. However, the amount of ex-alcohol consumption was comparatively more than current alcohol consumption in male hypertensive subjects. The results of Pearson correlation coefficient analyses indicated that there was no significant association between age, BMI, or blood pressures and the assessed vegetable consumption frequency (Table 8). By regression analyses, advancing age was strongly associated with systolic ( P = 0.0024) and diastolic ( P = 0.0024) blood pressures. Also, diastolic blood pressure was observed to be statistically significant for BMI ( P = 0.0037) and alcohol consumption ( P = 0.0002) (Table 9).

Table 9 Regression analyses of age, body mass index (BMI), and alcohol consumption to systolic and diastolic blood pressures in elderly Chinese Americans Independent variable

N

Systolic blood pressure (mm Hg), P value

Diastolic blood pressure (mm Hg), P value

Age (yr.) BMI (kg/m2) Alcohol consumption (mL/day)

205 205 97

0.0024 0.3164 0.3242

0.0024 0.0037 0.0002

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4. Discussion The purpose of this study was to assess the effects of age, gender, obesity, vegetable consumption frequency, and selected health habits on the incidence rate of hypertension in elderly Chinese Americans. Our findings may not represent all elderly populations because this was a biased, nonrandomized sample population selected from the nearby Los Angeles Chinese community. The study was cross-sectional rather than longitudinal, which potentially biased some of the observed results. However, because of temporal and fiscal limitations, a longitudinal study was not possible. It would be worthwhile to conduct future longitudinal studies to observe how the dietary patterns and health habits of elderly Chinese Americans change over time and the consequent effects on the hypertensive status of these individuals. Our results indicated that the percentage of hypertension was at about 40% in the total groups, which was slightly lower than the comparable age group (50%) of the general population [2]. However, the two major types of hypertension most common in older persons, isolated systolic hypertension and combined systolic-diastolic hypertension (6.0% and 3.7%, respectively), were much lower in this population than those of the comparable age group in the general population [2]. Furthermore, the prevalence rate of diastolic hypertension gradually declining with age (Table 2) may indicate that the lower DBP is a beneficial factor for the survival in the older group (group 3, z75 years). There was more borderline isolated systolic hypertension (BH) in women than in men. In contrast, there was more mild diastolic hypertension (MDH) observed in men than in women. The percentage of the prevalence rate of lean hypertensive subjects was greater than in obese hypertensive subjects in all age groups, and lean male hypertensive subjects were more prevalent than their female counterparts (30% vs 23%). Conversely, the percentage of the prevalence rate of obese hypertensive women was higher than their male counterparts (13% vs 6%). Lean hypertension seems to be the predominate form of hypertension for men and obese hypertension seems to be the physiological manifestation for women. Further studies need to be conducted to examine why obese women and lean men have a higher prevalence rate for hypertension. Also, in this population, the percentage of diastolic hypertension and combined hypertension were higher in men than those of their female counterparts (60% vs 40%, and 67% vs 33%, respectively). The majority of hypertensive subjects tended to consume vegetables, in particular PakCoy, once per day. A higher percentage of normotensive subjects consumed vegetables more frequently, especially Chinese greens or Pak-Coy (z2-3 times/day). Since our sample population (97 cases) was relatively small and nonrandomized, it would be presumptuous to suggest that Pak-Coy intake had a hypertensive effect whereas Chinese greens had a hypotensive effect. The daily consumption of vegetables, in particular Pak-Coy (once per day in most hypertensive subjects) may reflect their self-awareness or belief that eating Pak-Coy could help in lowering blood pressure. The consumption frequency of selected vegetables was probably compromised by factors such as the addition of condiments (salt and oil) while cooking. However, since the food composition and preparation methods were not surveyed in this population of elderly Chinese Americans, future studies should investigate whether composition and preparation methods have a profound impact on hypertension. In addition,

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the total consumption of vegetables/fruits may be more important than the consumption frequency on only selected vegetables. Significantly more men than women were reported as ex-alcohol drinkers and heavy drinkers (mean 73.5 mL/day of ethanol). Moreover, significantly more men than women were reported as former cigarette smokers. Consequently, there were significantly more male hypertensive subjects than those of female hypertensive subjects reported as ex-drinkers and ex-smokers. Also, male hypertensive subjects had a significantly longer history of habitual smoking. Male hypertensive subjects consumed more tea (cup/day) than those of female hypertensive subjects (mean 0.70 cup/day vs 0.34 cup/day, respectively). The active constituents of caffeine in tea could have been a risk factor for hypertension. For example, in a study conducted by Grifoni et al., oral administration of caffeine (30 mmol/L) in male Wistar rats induced rapid and phasic contractions in intact vascular endothelium [9]. The inherent weakness of this study was the high probability of inaccuracy in selfestimating the amount of alcohol consumption in cup(s)/day. The problem was further compounded by conversion from a larger volume unit, i.e., cup(s)/day, to a smaller volume unit (mL of ethanol/day). It was assumed that the calculated amount of alcohol consumption (N13 mL/day) was overestimated. Also, in assessing the mean percentage of hypertensive and normotensive cases in lean and obese subjects among the three age groups and between genders, many of the subjects could not be identified as lean or obese because their BMI ranged between 25 and 27 kg/m2. Consequently, their data could not be used in evaluating the prevalence rate of hypertension between lean and obese subjects. According to Cheng, the ideal body mass index for Chinese people is lowered in China because it takes smaller rises in BMI to induce the risk of hypertension, coronary artery disease, and type 2 diabetes in the Chinese population. In China, a BMI between 24 and 27.9 kg/m2 and z28 kg/m2 is considered overweight and obese, respectively [10]. Further analyses of age, BMI, vegetable consumption frequency, and health habits on blood pressures by Pearson correlation coefficient showed that there was no clear association between vegetable consumption frequency and blood pressures. However, by regression analyses, advancing age was associated with elevated systolic and diastolic blood pressures. In addition, there was no significant association between light alcohol (b13 mL of ethanol/ day) consumption and blood pressures. However, the effects of alcohol consumption on cardiovascular disease, more specifically hypertension, are complex. Many epidemiological studies have indicated that alcohol consumption exceeding 2 ounces/day can elevate blood pressures in adults of all ages [11]. In contrast, evidence of moderate alcohol consumption has been observed to increase levels of high-density lipoprotein and its subfractions which can decrease myocardial infarctions [12]. In this study, diastolic blood pressure was associated with alcohol consumption (milliliters of ethanol per day) ( P = 0.0002). Since the type of alcohol consumed was not categorized in this study, it would be worthwhile to conduct future research to ascertain whether the type of alcohol consumed (e.g., beer, wine, or spirits) could increase or reduce blood pressure levels. Advanced age, male gender, and leanness may be risk factors in the development and progression of hypertension in elderly Chinese Americans. Studies have shown that the mortality rate for men is twice that of women due to the higher incidence of heart disease in men [13]. Also, additive risk effects in the development of hypertension appear to be more

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prevalent in lean men with a combined history of drinking and smoking. For Chinese women, the combination of advanced age and obesity appear to be risk factors for hypertension. Even though 25% of the adult population have hypertension, synthetic antihypertensive treatment has effectively regulated blood pressure in only about 50% of patients treated in the United States [2]. Adhering to synthetic antihypertensive therapy is a major complication due to the numerous side effects caused by treatment, such as vomiting, nausea, heart attacks, and strokes [14]. While the type and quantity of medication used by elderly Chinese Americans was not surveyed in this study, it would be significant to investigate in future studies the efficacy of synthetic antihypertensive medication in comparison to altering specific dietary patterns and health habits. The introduction of antihypertensive therapy that is efficient, safe, affordable, and accessible for daily supplementation would provide Chinese Americans significant medical advantages in the fight against hypertension. One nutritional antihypertensive therapy available to hypertensive patients is the Dietary Approaches to Stop Hypertension (DASH) diet. The DASH diet promotes the consumption of fruits, vegetables, low-fat dairy products, whole grains, fish, poultry, and nuts. The diet reduces the consumption of total fat, red meats, processed sugars, and sugar-containing beverages [15]. The DASH program approximates a 2000-kcalorie diet that intentionally promotes weight loss, a significant factor in reducing hypertension in obese patients [16]. The advantage of using the DASH diet versus synthetic drug treatment for reducing hypertension is that this dietary pattern can be adapted into one’s lifestyle for safe long-term use. Even though numerous epidemiological studies have demonstrated that the DASH diet can reduce hypertension with minimal side effects, the majority of the population in the United States does not know that this remedy exists. Essentially, more studies need to be conducted on antihypertensive nutritional therapies and programs must be implemented to inform the general public about the benefits of using these alternative treatments. Additionally, further studies should be conducted on the potential side effects of using alternative antihypertensive nutritional treatments in association with traditional antihypertensive medication. It is believed that 50% of arterial diseases and hypertension can be attributed to dietary intake in the United States [17]. Also, it is indicated that more than 100 million residents in China have unfavorable blood pressure levels and that even a reduction of 2 mm Hg in systolic or diastolic blood pressures would significantly decrease the incidence of strokes and coronary heart diseases in China [18]. We must use these known facts to uncover further nutritional antihypertensive treatments that will promote the long-term health of our young and elderly populations.

References [1] Hosseini S, Lee J, Sepulveda T, Rohdewald P, Watson R. A randomized double-blind, placebo-controlled, prospective, 16 week crossover study to determine the role of Pycnogenol in modifying blood pressure in mildly hypertensive patients. Nutr Res 2001;21:1251 - 60. [2] Svetkey LP, Harsha DW, Vollmer WM, Steven VJ, Obarzanek E, Elmer PJ, et al. PREMIER: a clinical trial of comprehensive lifestyle modification for blood pressure control: rationale, design, and baseline characteristics. AEP 2003;13:1 - 10.

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