| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
(Hypertension. 2001;38:821.)
© 2001 American Heart Association, Inc.
Scientific Contributions |
From the Department of Medicine, University of Western Australia, Royal Perth Hospital and West Australian Heart Research Institute, Perth, Australia.
Correspondence to Dr V. Burke, University Department of Medicine, Royal Perth Hospital, rear of 50 Murray St, Box X2213 GPO, Perth WA 6847, Australia. E-mail vburke{at}cyllene.uwa.edu.au
| Abstract |
|---|
|
|
|---|
Key Words: diet blood pressure blood pressure monitoring, ambulatory
| Introduction |
|---|
|
|
|---|
2 mm Hg, relative to control subjects,10 in 35- to 65-year-old Chinese subjects with untreated high-normal BP. Dietary fiber may also be related inversely to BP.2,1113 A recent meta-analysis14 concluded that fiber probably has a small BP-lowering effect. In Chinese populations, BP has been associated inversely with both protein and fiber intake,2 consistent with additive effects. However, associations with specific nutrients may arise through other dietary or lifestyle differences that affect BP.
Given the worldwide prevalence of hypertension, it is important to resolve whether dietary protein and fiber can influence BP alone or additively. We therefore conducted a randomized controlled trial in treated hypertensives in whom protein or fiber intake, or both, was increased against a background of a standardized diet low in both constituents.
| Methods |
|---|
|
|
|---|
20 years old and were receiving drug therapy for hypertension were recruited via advertisement. Inclusion criteria included drug therapy for
6 months with
2 antihypertensive agents, SBP between 130 and 160 mm Hg, and alcohol intake of
210 g alcohol/wk. Exclusion criteria included diabetes, renal disease (creatinine >130 mmol/L), symptomatic heart disease, regular use of nonsteroidal anti-inflammatory drugs, psychiatric illness, or body mass index of >33 kg/m2 for men and >37 kg/m2 for women. The study was approved by the University of Western Australia Committee for Human Rights, and all participants gave written consent.
Dietary Intervention
During the initial 4-week period (baseline), subjects followed their usual diet, and nutrient intake was assessed individually from 3-day weighed-food records to establish isoenergetic, weight-maintenance diets for the subsequent intervention. In the next 4 weeks (familiarization period), subjects were supplied home-delivered meals that provided 12.5% of energy from protein and 15 g fiber/d. Participants then entered into an 8-week-long study of factorial design in which they were randomized to continue the 12.5% protein15 g fiber/d diet (low fiber, low protein) or to consume a protein additive to provide a total of 25% energy as protein. Within each arm, subjects were further randomized to continue the low fiber intake or to consume an additional 15 g psyllium/d, providing 12 g soluble fiber/d. The low-protein diet provided an intake of protein equal to the 10th percentile for the average Australian diet, and the supplements equaled a protein intake of the 90th percentile.15
Protein was provided as 66 g soy protein/d (Archer Daniels Midland Co). The equivalent energy intake was provided as a supplement of 66 g maltodextrin powder/d (Starch Australasia Ltd) in groups not consuming the soy supplement. Soluble fiber was provided as psyllium husks from a single batch (DHA Pty Ltd Designer Wise Foods). Supplements were provided as weighed daily amounts to be taken as a drink mixed with juice or water throughout the day; these consisted of (1) maltodextrin only in the low-fiber, low-protein group; (2) soy protein only in the low-fiber, high-protein group; (3) psyllium with maltodextrin in the high-fiber, low-protein group; and (4) soy protein with psyllium in the high-fiber, high-protein group. Because the soy protein was higher in potassium than the maltodextrin or psyllium supplements, an additional 786 mg potassium/d, as potassium chloride, was added to the nonprotein supplements.
Dietary meals (lunch, dinner, snack, and fruit drinks) with specified nutrient content were obtained from Home Chef. Participants provided breakfasts, based on a list of permissible low-fiber cereals or low-fiber white bread. Meals were based on 2 serving sizes, supplying
8 and
10 MJ/d, respectively. Participants were instructed on appropriate deviations from their supplied meals to ensure that energy requirements were met and not exceeded. Individual adjustments were made as needed based on food diaries, weight monitoring, and weekly reviews with the same dietician. Compliance with the supplements was monitored by weekly issue of counted sachets and a final check on the number of sachets returned at the end of the study. Urinary urea provided a further check on compliance in the groups receiving protein supplements. Alcohol intake was assessed using 7-day retrospective diaries at the end of baseline, familiarization, and intervention periods.
Block randomization was carried out at the end of familiarization using computer-generated randomly assigned numbers provided by the statistician. Differences in taste and texture of the supplements prevented blinding of the participants and the staff carrying out the intervention, who also needed to provide specific dietary advice to participants who had difficulty in compliance with the intervention. Outcome assessment depended on electronically recorded ambulatory BP data and was independent of assessment by trial staff.
Anthropometry, Biochemical Variables, and Lifestyle Monitoring
Weight was recorded weekly; height was measured with a stadiometer. During the weekly visits, any changes in alcohol intake, physical activity, health status, and medication use were monitored by interview. Laboratory measurements, carried out at baseline and at the end of each study period, included serum electrolytes, urea, creatinine, uric acid, and 24-hour urinary creatinine, sodium, and potassium.
Ambulatory BP Monitoring
BP was recorded over 24 hours at the end of baseline, familiarization, and intervention with an Accutracker II (model 104; Suntech). BP was recorded every 30 minutes during waking hours and every hour during sleep. A nurse fitted the monitor and explained its use to the volunteers, who completed diaries describing their activity at the time that ambulatory BP (ABP) was recorded. If the pulse pressure was <20 mm Hg or readings were associated with a test code, they were excluded from the analysis.
Statistical Analysis
Xyris software, based on the 1995 Australian NUTTAB database, was used to assess nutrient intake. Characteristics of groups at baseline were compared by ANOVA. Effects of dietary change on change in 24-hour, awake, and asleep SBP, DBP, and heart rate were examined using pooled time series random effects models (PROC MIXED; SAS Institute) with change in mean 24-hour ABP as the primary outcome measure. Age, gender, change in weight, change in urinary sodium, and change in alcohol intake were included in subsequent models. P<0.05 was considered significant.
| Results |
|---|
|
|
|---|
|
|
Nutrient Intake
Analysis of nutrient intake confirmed compliance with the diets, showing a significant increase in protein, fiber, or carbohydrate intake appropriate to group allocation (Table 2). There were no other significant changes in dietary variables with no significant between-group differences in sodium or potassium intake, confirming that potassium added to the low-protein supplements achieved intakes equivalent to those from the soy protein supplements.
|
Body Weight, Urinary Analytes, and Antihypertensive Drugs
There were no significant differences in body weight related to the intervention (Table 3). Urine urea increased significantly with higher protein intake (mean change relative to nonprotein groups, 228.4 mmol/L; 95% confidence limits [CL], 156.1 and 300.7 mmol/L), but there was no significant change in the group with fiber only (net mean change, -121.3 mmol/L; 95% CL, -375.0 to 132.5 mmol/L). Changes in serum creatinine and urea and urinary potassium, sodium, sodium/potassium ratio, and creatinine did not differ significantly between treatment groups. Except for the 1 patient who withdrew from the study, there was no change in the dose or type of antihypertensive medication during the trial.
|
ABP and Heart Rate
Table 3 shows the mean 24-hour SBP, DBP, and heart rate at the end of familiarization and at the end of intervention, with the greatest fall in BP in the high-fiber, high-protein group. Net changes in mean 24-hour, asleep, and awake SBP, DBP, and heart rate for main effects are shown in Table 4. Random effects models showed significant independent effects of fiber and protein on 24-hour SBP and awake SBP and a significant effect of protein on asleep SBP. Interactions between protein and fiber were not significant. Change in 24-hour and awake DBP was significantly related to protein but not to fiber. Changes in BP were independent of age, gender, and changes in weight, alcohol intake, and urinary sodium or potassium excretion. Protein significantly reduced 24-hour and awake heart rates.
|
Relative to control subjects, 24-hour mean SBP fell by 2.4 mm Hg (95% CL, -10.0 and 5.2 mm Hg) in the high-fiber, low-protein group; by 2.9 mm Hg (95% CL, -14.5 and 2.8 mm Hg) in the low-fiber, high-protein group; and by 10.5 mm Hg (95% CL, -20.4 and -0.6 mm Hg) in the high-fiber, high-protein group. Net decreases for DBP were 1.9 mm Hg (95% CL, -7.8 and 4.0 mm Hg), 2.5 mm Hg (95% CL, -6.6 and 1.6 mm Hg), and 3.6 mm Hg (95% CL, -8.3 and 1.1 mm Hg), respectively, whereas heart rate increased by 3.5 bpm (95% CL, -5.7 and 12.7 bpm) in the high-fiber, low-protein group and fell by 0.5 bpm (95% CL, -5.4 and 4.4 bpm) in the low-fiber, high-protein group and by 1.7 bpm (95% CL, -5.8 and 3.1 bpm) in the high-fiber, high-protein group.
| Discussion |
|---|
|
|
|---|
6 mm Hg both with soy protein sufficient to increase protein intake from the 10th to the 90th percentile for Australian diets15 and with psyllium supplements that doubled the fiber intake. Additive effects of protein and fiber produced the greatest fall in BP in the group that received both supplements. Our findings are consistent with population studies that link lower BP with higher intake of protein and fiber and indicate a causal association. Population studies suggest an inverse association between SBP and protein intake of either animal or vegetable origin. Among rural Japanese, a higher ratio of urinary sulfate to nitrogen, reflecting the intake of animal protein, was related to lower SBP in men.16 In a 7-year prospective study in the United States, in which animal products are the main source of dietary protein, a change in SBP related inversely to protein intake at baseline.5 Similar inverse relationships have been reported for the intake of vegetable protein2,4 and animal protein.6,7
Amino acid content of proteins may be relevant to effects on BP.17 L-Arginine, acting via NO,18 lowers BP and improves endothelial function. Taurine lowers BP in animals19 and is inversely related to BP in population studies.20 A nonspecific dose-dependent diuretic effect of amino acids may also contribute to the BP-lowering effect.21
There are no satisfactory controlled trials that compare the effects of both the quantity and the type of protein on BP (see Beilin8 for a review). We used a supplement of soy protein rather than of animal protein to minimize changes in other nutrients, but soy proteins contain isoflavones, which may themselves have cardiovascular effects.22 Soy protein supplements that provide 118 mg isoflavone/d reduced SBP by 7.5 mm Hg in men and postmenopausal women.23 In a randomized controlled trial, 55 mg isoflavonoids/d, on a background of a usual diet, had no significant effect on ABP in men or women,24 consistent with the report that BP in women was unchanged by 80 mg isoflavones/d.25 In the present study, soy protein provided 23 mg isoflavones/d, and it is unlikely that the isoflavone content alone accounts for the findings.
Several epidemiological studies have shown an inverse association between dietary fiber and BP2,1113 or the development of hypertension,12 and clinical trials suggest a small antihypertensive effect.14 Inconsistent results of fiber supplement studies may have arisen from variations in types of fibers and background diets. In stroke-prone spontaneously hypertensive rats, psyllium attenuated salt-accelerated hypertension,26 an effect that the authors suggested may be explained by increased fecal excretion of sodium bound to the soluble fiber. Soluble fiber seems more likely to induce cardiovascular effects.
Estimates from the International Study of Salt and Blood Pressure (INTERSALT) study1 suggest that an increase of 37 g dietary protein/d, less than the 66 g/d used in the present study, would lead to falls in population mean SBP of
3 mm Hg, sufficient to substantially reduce population morbidity and mortality rates from cardiovascular diseases.27 These findings therefore have important implications for the prevention and management of hypertension. In developing populations, a high prevalence of hypertension occurs against a background of a low intake of protein and fiber and high dietary salt consumption. However, even in industrialized countries, there are wide discrepancies in dietary fiber and protein intakes, in large part related to socioeconomic status. Our findings suggest that adequate intake of protein and fiber, particularly with fruits and vegetables as sources of soluble fiber, should be considered in recommendations of an optimal diet for reduction of cardiovascular risk in subjects with normal renal function. Epidemiological studies on the whole suggest that low-fat animal products may be equally effective protein sources for lowering BP, whereas fish, fruit, and vegetables have a variety of other constituents thought to be of benefit for cardiovascular health.
| Acknowledgments |
|---|
Received November 9, 2000; first decision December 13, 2000; accepted April 4, 2001.
| References |
|---|
|
|
|---|
2. He J, Klag MJ, Whelton PK, Chen JY, Qian MC, He GQ. Dietary macronutrients and blood pressure in southwestern China. J Hypertens. 1995; 13: 12671274.[Medline] [Order article via Infotrieve]
3. Stamler J, Caggiula A, Granditz GA. Relationships of dietary variables to blood pressure (BP): findings of the Multiple Risk Factor Intervention Trial. Circulation. 1992; 85: 867.
4.
Liu K, Ruth K, Flack J, Jones-Webb R, Burke G, Savage PJ, Hulley SB. Blood pressure in young blacks and whites: relevance of obesity and lifestyle factors in determining differences: the CARDIA Study. Circulation. 1996; 93: 6066.
5. Liu K, Ruth KJ, Shekelle RB, Stamler J. Macronutrients and long-term change in systolic blood pressure. Circulation. 1993; 87: 679.
6. Zhou B, Wu X, Tao S Q, Yang J, Cao TX, Zheng RP, Tian XZ, Lu CQ, Miao HY, Ye FM. Dietary patterns in 10 groups and the relationship with blood pressure. Chin Med J. 1989; 102: 257261.[Medline] [Order article via Infotrieve]
7.
Zhou B, Zhang X, Zhu A, Zhao L, Zhu S, Ruan L, Zhu L, Liang S. The relationship of dietary animal protein and electrolytes to blood pressure: a study on three Chinese populations. Int J Epidemiol. 1994; 23: 716722.
8.
Beilin LJ. Vegetarian and other complex diets, fats, fiber, and hypertension. Am J Clin Nutr. 1994; 59 (5 Suppl): 1130S1135S.
9. Yamori Y, Horie R, Nara Y, Ikeda K, Kihara M, Ooshima A, Fukase M. Genetics of hypertensive diseases: experimental studies on pathogenesis, detection of predisposition and prevention. Adv Nephrol. 1981; 10: 5174.
10. He J, Wu X, Gu D, Duan X, Whelton PK. Soybean protein supplementation and blood pressure: a randomized controlled clinical trial. Presented at the 40th Annual Conference on Cardiovascular Disease Epidemiology and Prevention, American Heart Association, La Jolla, Calif, 2000.
11.
Appel LJ, Moore TJ, Obarzanek E, Vollmer WM, Svetkey LP, Sacks FM, Bray GA, Vogt TM, Cutler JA, Windhauser MM, Lin PH, Karanja N. A clinical trial of the effects of dietary patterns on blood pressure. DASH Collaborative Research Group. N Engl J Med. 1997; 336: 11171124.
12.
Ascherio A, Rimm EB, Giovanucci EL, Colditz GA, Rosner B, Willett WC, Sacks F, Stampfer MJ. A prospective study of nutritional factors and hypertension among US men. Circulation. 1992; 86: 14751484.
13. Stamler J, Caggiula AW, Grandits GA. Relation of body mass and alcohol, nutrient, fiber, and caffeine intakes to blood pressure in the special intervention and usual care groups in the Multiple Risk Factor Intervention Trial. Am J Clin Nutr. 1997; 65: 338365.
14. He J, Whelton PK, Klag MJ. Dietary fiber supplementation and BP reduction: a meta-analysis of controlled trials. Presented at the 16th Scientific Meeting of the International Society of Hypertension, Glasgow, UK, 1996.
15. McLennan W, Podger A,eds. National Nutrition Survey: Nutrient Intakes and Physical Measurements. Australia 1995. Canberra, Australia: Australian Bureau of Statistics; 1998: 85.
16.
Kihara M, Fujikawa J, Ohtaka M, Mano M, Nara Y, Horie R, Tsunematsu T, Note S, Fukase M, Yamori Y. Interrelationships between blood pressure, sodium, potassium, serum cholesterol and protein intake in Japanese. Hypertension. 1984; 6: 736742.
17. Anderson GH. Proteins and aminoacids: effects on the sympathetic nervous system and blood pressure regulation. Can J Physiol Pharmacol. 1986; 64: 863870.[Medline] [Order article via Infotrieve]
18. Pedrinelli R, Ebel M, Catapano G, DellOmo G, Ducci M, Del Chicca M, Clerico A. Pressor, renal and endocrine effects of L-arginine in essential hypertension. Eur J Clin Pharmacol. 1995; 48: 195201.[Medline] [Order article via Infotrieve]
19. Fujita T, Sato Y. Hypotensive effect of taurine: possible involvement of the sympathetic nervous system and endogenous opiates. J Clin Invest. 1988; 82: 993997.
20. Nittynen L, Nurminen ML. Korpela R, Vapaatalo H. Role of arginine, taurine and homocysteine in cardiovascular diseases. Ann Med. 1999; 31: 318326.[Medline] [Order article via Infotrieve]
21.
Cernadas MR, Lopez-Farre A, Riesco A, Gallego MJ, Espinosa G, Diguini E, Hernado L, Casado S, Caramelo C. Renal and systemic effects of amino acids administered separately: comparison between L-arginine and non-nitric oxide donor amino acids. J Pharmacol Exp Ther. 1992; 263: 10231029.
22. Adlercreutz H. Western diet and western diseases: some hormonal and biochemical mechanisms and associations. Scand J Clin Lab Invest. 1990; 50 (Suppl 201): 323.
23. Teede HJ, Dalais FS, Kotsopoulos D, Liang YL, Davis SR, McGrath BP. Phytoestrogen dietary supplementation improves lipid profiles and blood pressure: a double blind, randomised, placebo-controlled study in men and postmenopausal women. Climacteric. 1999; 2 (Suppl 1): 127.
24. Hodgson JM, Puddey IB, Beiln LJ, Mori TA, Burke V, Croft KD, Rogers PB. Effects of isoflavonoids on blood pressure in subjects with high-normal ambulatory blood pressure levels: a randomized controlled trial. Am J Hypertens. 1999; 12: 4753.[Medline] [Order article via Infotrieve]
25.
Nestel PJ, Yamshita T, Sashra T, Pomeroy S, Dart A, Komesaroff P, Owen A, Abbey M. Soy isoflavones improve systemic arterial compliance but not plasma lipids in menopausal and perimenopausal women. Arterioscler Thromb Vasc Biol. 1997; 17: 33923398.
26. Obata K, Ikeda K, Yamasaki M, Yamori Y. Dietary fiber, psyllium, attenuated salt-accelerated hypertension in stroke-prone spontaneously hypertensive rats. J Hypertens. 1998; 16: 19591964.[Medline] [Order article via Infotrieve]
27.
Cook NR, Cohen J, Herbert PR, Taylor JO, Hennekens CH. Implications of small reductions in diastolic blood pressure for primary prevention. Arch Intern Med. 1995; 155: 701709.
This article has been cited by other articles:
![]() |
Y. P Lee, T. A Mori, I. B Puddey, S. Sipsas, T. R Ackland, L. J Beilin, and J. M Hodgson Effects of lupin kernel flour-enriched bread on blood pressure: a controlled intervention study Am. J. Clinical Nutrition, March 1, 2009; 89(3): 766 - 772. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Kan, J. Stevens, G. Heiss, R. Klein, K. M Rose, and S. J London Dietary fiber intake and retinal vascular caliber in the Atherosclerosis Risk in Communities Study Am. J. Clinical Nutrition, December 1, 2007; 86(6): 1626 - 1632. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Djousse and J. M. Gaziano Breakfast Cereals and Risk of Heart Failure in the Physicians' Health Study I Arch Intern Med, October 22, 2007; 167(19): 2080 - 2085. [Abstract] [Full Text] [PDF] |
||||
![]() |
F. Muzio, L. Mondazzi, W. S Harris, D. Sommariva, and A. Branchi Effects of moderate variations in the macronutrient content of the diet on cardiovascular disease risk factors in obese patients with the metabolic syndrome Am. J. Clinical Nutrition, October 1, 2007; 86(4): 946 - 951. [Abstract] [Full Text] [PDF] |
||||
![]() |
T. Jauhiainen and R. Korpela Milk Peptides and Blood Pressure J. Nutr., March 1, 2007; 137(3): 825S - 829S. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. M Hodgson, V. Burke, L. J Beilin, and I. B Puddey Partial substitution of carbohydrate intake with protein intake from lean red meat lowers blood pressure in hypertensive persons. Am. J. Clinical Nutrition, April 1, 2006; 83(4): 780 - 787. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. J. Appel, M. W. Brands, S. R. Daniels, N. Karanja, P. J. Elmer, and F. M. Sacks Dietary Approaches to Prevent and Treat Hypertension: A Scientific Statement From the American Heart Association Hypertension, February 1, 2006; 47(2): 296 - 308. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Elliott, J. Stamler, A. R. Dyer, L. Appel, B. Dennis, H. Kesteloot, H. Ueshima, A. Okayama, Q. Chan, D. B. Garside, et al. Association Between Protein Intake and Blood Pressure: The INTERMAP Study Arch Intern Med, January 9, 2006; 166(1): 79 - 87. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. J. Appel, F. M. Sacks, V. J. Carey, E. Obarzanek, J. F. Swain, E. R. Miller III, P. R. Conlin, T. P. Erlinger, B. A. Rosner, N. M. Laranjo, et al. Effects of Protein, Monounsaturated Fat, and Carbohydrate Intake on Blood Pressure and Serum Lipids: Results of the OmniHeart Randomized Trial JAMA, November 16, 2005; 294(19): 2455 - 2464. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. He, D. Gu, X. Wu, J. Chen, X. Duan, J. Chen, and P. K. Whelton Effect of Soybean Protein on Blood Pressure: A Randomized, Controlled Trial Ann Intern Med, July 5, 2005; 143(1): 1 - 9. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. A. Cutler and E. Obarzanek Nutrition and Blood Pressure: Is Protein One Link? Toward a Strategy of Hypertension Prevention Ann Intern Med, July 5, 2005; 143(1): 74 - 75. [Full Text] [PDF] |
||||
![]() |
G. Yang, X.-O. Shu, F. Jin, X. Zhang, H.-L. Li, Q. Li, Y.-T. Gao, and W. Zheng Longitudinal study of soy food intake and blood pressure among middle-aged and elderly Chinese women Am. J. Clinical Nutrition, May 1, 2005; 81(5): 1012 - 1017. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. Cordain, S B. Eaton, A. Sebastian, N. Mann, S. Lindeberg, B. A Watkins, J. H O'Keefe, and J. Brand-Miller Origins and evolution of the Western diet: health implications for the 21st century Am. J. Clinical Nutrition, February 1, 2005; 81(2): 341 - 354. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. T. Streppel, L. R. Arends, P. van 't Veer, D. E. Grobbee, and J. M. Geleijnse Dietary Fiber and Blood Pressure: A Meta-analysis of Randomized Placebo-Controlled Trials Arch Intern Med, January 24, 2005; 165(2): 150 - 156. [Abstract] [Full Text] [PDF] |
||||
![]() |
L. J. Beilin, V. Burke, and I. B. Puddey Effects of Exercise and Weight Loss on Hypertension JAMA, August 20, 2003; 290(7): 887 - 887. [Full Text] [PDF] |
||||
![]() |
D. Mozaffarian, S. K. Kumanyika, R. N. Lemaitre, J. L. Olson, G. L. Burke, and D. S. Siscovick Cereal, Fruit, and Vegetable Fiber Intake and the Risk of Cardiovascular Disease in Elderly Individuals JAMA, April 2, 2003; 289(13): 1659 - 1666. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. Stamler, K. Liu, K. J. Ruth, J. Pryer, and P. Greenland Eight-Year Blood Pressure Change in Middle-Aged Men: Relationship to Multiple Nutrients Hypertension, May 1, 2002; 39(5): 1000 - 1006. [Abstract] [Full Text] [PDF] |
||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
Hypertension Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 2001 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |