|
 |
|
|||||||
|
|||||||||
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
© American Diabetes Association ®, Inc., 2006
Medical Nutrition Therapy for Hypertension and Albuminuria
 |
Abstract |
|---|
 Top Abstract IntroductionMEDICAL NUTRITION THERAPY FOR...MNT FOR THE TREATMENT...PUTTING NUTRITION...SUMMARYReferences |
|---|
In Brief
Modest weight reduction, the Dietary Approaches to Stop Hypertension eating plan, sodium reduction, physical activity, and moderation in alcohol intake are effective in lowering blood pressure and preventing hypertension. However, combining these lifestyle interventions is more effective than single approaches. Potassium supplementation can help control or prevent hypertension. Other lifestyle factors—dietary fiber, calcium, magnesium, fish oil intakes—have been studied but have uncertain efficacy. To delay the progression of nephropathy, the first priority of medical nutrition therapy is to assist in glucose and blood pressure control. In addition, instituting a low-protein diet has been shown to improve renal function in people with diabetes.
|
Introduction |
|---|
|
TopAbstractIntroductionMEDICAL NUTRITION THERAPY FOR...MNT FOR THE TREATMENT...PUTTING NUTRITION...SUMMARYReferences |
|---|
Lifestyle modifications play a crucial role in controlling hypertension. Hypertension is often present in people who are overweight or obese, are sedentary, smoke, or drink alcohol in excess. These factors make elevated blood pressure difficult to control, despite progressively increasing doses of multiple medications.1 Lifestyle modifications are equally as important for people without the above concerns but who are genetically predisposed to develop hypertension. For people with microalbuminuria, controlling blood pressure and achieving near-normoglycemia slows the progression to macroalbumininuria and end-stage renal disease.2 Lifestyle modifications can positively affect both blood pressure and glucose control. Moderate protein restriction can also contribute to slowing the progression of nephropathy.
|
MEDICAL NUTRITION THERAPY FOR THE TREATMENT OF HYPERTENSION |
|---|
|
TopAbstractIntroductionMEDICAL NUTRITION THERAPY FOR...MNT FOR THE TREATMENT...PUTTING NUTRITION...SUMMARYReferences |
|---|
Lifestyle modifications have been shown to lower blood pressure, enhance effectiveness of antihypertensive drug therapy, and reduce overall cardiovascular risk.3,4 However, few studies have been carried out exclusively in people with diabetes. Therefore, lifestyle recommendations for people with diabetes are by necessity extrapolated from studies in the general population. Along with the lifestyle modifications discussed below, interventions to stop smoking are of primary importance.
The effects of lifestyle modifications are dose and time dependent and therefore can be greater for some individuals than others and may have greater benefits when combined. It is important for clinicians to know the potential outcomes from medical nutrition therapy (MNT) in the majority of people. Lifestyle recommendations to manage hypertension and their potential to reduce blood pressure are summarized in Table 1.3
|
Weight Reduction
In people with diabetes, there is a general association between weight
reduction and a reduction in blood pressure, but there is a great deal of
variability in this response. In almost all weight-reduction studies in the
general population, systemic blood pressure is reduced even if the degree of
weight loss is
small.1 Overall, the
greater the weight loss, the greater the reduction in blood pressure. In a
meta-analysis5 of 11
weight-loss trials, the average systolic and diastolic blood pressure
reductions per kilogram of weight loss were 2 and 1 mmHg, respectively. In the
Trials of Hypertension
Prevention,6 weight
loss (goal of 4.5-kg loss) alone or in combination with sodium restriction
lowered the incidence of hypertension; however, behavior changes tended not to
be sustained over time, thus diminishing the positive effects on blood
pressure.
DASH Eating Plan
The Dietary Approaches to Stop Hypertension (DASH)
Study7 evaluated the
effects on blood pressure of three dietary patterns: 1) a control
diet that was similar to a traditional American diet, 2) a diet high
in fruit and vegetables, and 3) the DASH diet, which was higher in
fruits, vegetables, and low-fat dairy products and lower in total fat,
saturated fat, and cholesterol. Sodium intake, physical activity, and body
weight remained constant. Both test diets lowered blood pressure compared to
the control diet. However, the DASH diet lowered systolic and diastolic blood
pressure by 8 and 6 mmHg, respectively. The diet was effective in all
subgroups, although systolic blood pressure in African Americans and
hypertensive individuals decreased more than in whites and nonhypertensive
individuals.
Dietary Sodium Intake
Although blood pressure response to a reduction in sodium appears to vary
widely, when different levels of sodium were used in conjunction with the DASH
diet in people with and without hypertension, the lower the sodium intake, the
greater the lowering of blood
pressure.8 The
effects were greater in hypertensive individuals, African Americans, and
women. Compared to the control diet, which was high in sodium (3.6 g), the
DASH diet with its low sodium level (1.2 g) led to a mean systolic blood
pressure 11.5 mmHg lower in participants with hypertension and 7.1 mmHg lower
in participants without hypertension. The intermediate diet (2.4 g sodium) had
an effect between those of the high- and low-sodium diets. Furthermore, the
DASH diet and reduced-sodium eating plan has effects similar to single-drug
therapy.8
Several meta-analyses have examined the relationship between sodium intake
and blood pressure. A meta-analysis by He and
MacGregor9 assessed
the effect of modest salt reduction on blood pressure in trials with a
duration 
4 weeks. A total of 17 trials in hypertensive subjects and 11
trials in normotensive subjects were included. In hypertensive subjects, the
decrease in systolic blood pressure was 5.0 mmHg, and in diastolic blood
pressure it was 2.7 mmHg. In normotensive subjects, systolic blood pressure
decreased 2.0 mmHg, and diastolic blood pressure decreased 0.3 mmHg. The
weighted linear regression analyses showed a dose response between the change
in urinary sodium and blood pressure. The authors concluded that a modest
reduction in salt intake for a duration of 4 weeks does have a
significant and, from a population viewpoint, important effect on blood
pressure.
The response to sodium reduction may be greater in subjects who are salt-sensitive, a factor that may apply to many individuals with diabetes.10,11 Reducing sodium intake can best be done by avoiding processed foods, the source of 75% of sodium intake in the usual diet. Other tips for cutting back on salt (sodium) are listed in Table 2.
|
Physical Activity
Two
meta-analyses12,13
have demonstrated the beneficial effects of exercise on blood pressure. The
first analysis12
showed that walking reduced resting systolic and diastolic blood pressure in
adults by an average of 3 mmHg. In the second, in 54 randomized clinical
trials, aerobic exercise reduced systolic blood pressure an average of 4 mmHg
and diastolic blood pressure 2 mmHg, irrespective of changes in body
weight.13 Thus,
increasing the amount of low- to moderate-intensity physical activity to
30–45 minutes most days of the week is an important adjunct to other
lifestyle strategies.
Moderate Alcohol Intake
The association between alcohol consumption and risk of chronic
hypertension appears to follow a J-shaped curve, with light-to-moderate intake
associated with a decrease in cardiovascular risk and excessive and chronic
intake associated with an increased risk of
hypertension.14
Moderate intake of alcohol is usually defined as 
2 alcoholic drinks per
day for adult men and 1 alcoholic drink per day for adult women. One
drink is defined as 12 oz of beer, 5 oz of wine, or 1 1/2 oz of distilled
spirits (
15 g alcohol). A
meta-analysis15 of
15 randomized controlled trials examined the effects of alcohol on blood
pressure in heavy drinkers. A reduction of alcohol to moderate intakes reduced
systolic and diastolic blood pressure by 3.3 and 2.0 mmHg, respectively.
Dietary Fiber
A
meta-analysis16 of
24 randomized placebo-controlled trials was done to estimate the effect of
fiber supplementation on blood pressure. Fiber supplementation (average dose
11.5 g/day) lowered systolic blood pressure by 1.1 mmHg and diastolic blood
pressure by 1.3 mmHg. Reductions tended to be larger in older (> 40 years)
and hypertensive populations than in younger and normotensive ones. An earlier
meta-analysis17 of
12 randomized controlled trials published before 1995 found a similar effect:
an average reduction in blood pressure of 1.2/1.8 mmHg with dietary fiber
supplements averaging 14 g/day.
Potassium, Calcium, Magnesium, and Fish Oils
Clinical trials have reported a beneficial effect of potassium
supplementation on blood pressure. A
meta-analysis18
found that high dietary potassium intake may help prevent and control
hypertension. Most population studies have found no significant relationship
between calcium and the prevalence of hypertension. However, a
meta-analysis19
showed a small reduction in blood pressure with the use of calcium
supplements. In most clinical studies, magnesium supplementation has been
ineffective in altering blood pressure, possibly because of the confounding
effects of antihypertensive medications and the short duration of the
studies.20 Thus,
the role of calcium and magnesium supplementation in preventing or treating
hypertension is unknown. Nonetheless, a DASH-type diet that includes fruits
and vegetables (five to nine servings per day) and low-fat dairy products (two
to four servings per day) will be rich in potassium, magnesium, and calcium
and may contribute to a reduction in blood pressure.
More recently, studies have shown that supplementation with large doses of fish oil (median dose of 5.7 g/day) can produce a modest reduction in blood pressure of 2.1/1.6 mmHg, especially in older hypertensive people.21
The National High Blood Pressure Education Program cautions that some widely publicized approaches have less proven or uncertain efficacy.22 Specifically, they mention calcium and fish oil supplements that lower blood pressure only slightly in individuals with hypertension. In addition, they caution that the ability of herbal and botanical supplements to safely lower blood pressure is unproven, and these products can interact adversely with medications. Lifestyle modifications shown to be beneficial for hypertension management and prevention are summarized in Table 3.
|
Combining Lifestyle Interventions
Most encouraging are the trials implementing multiple lifestyle
modifications and showing that combining lifestyle interventions can lower
blood pressure more effectively than single approaches. Two
trials23,24
evaluated the efficacy of implementing simultaneously multiple lifestyle
modifications: sodium reduction, weight loss, the DASH diet, and regular
physical activity. The Diet, Exercise, and Weight Loss Intervention
Trial23 randomized
hypertensive participants to a lifestyle change or control group. At the end
of the 9-week intervention, net reductions in 24-hour ambulatory systolic and
diastolic blood pressure were 9.5 and 5.3 mmHg, respectively, and changes in
daytime systolic and diastolic blood pressure were 12.1 and 6.6 mmHg,
respectively. In the PREMIER
trial24 of
hypertensive adults, multicomponent, behavioral interventions or multiple
behavioral interventions plus DASH were compared to an "advice
only" control group. In the multiple behavioral interventions plus DASH
group, the mean net reduction in systolic blood pressure was 11.1 mmHg, and in
diastolic blood pressure it was 6.4 mmHg. Both studies concluded that in
people with hypertension, a comprehensive lifestyle intervention program can
substantially lower blood pressure and reduce cardiovascular disease risk.
|
MNT FOR THE TREATMENT OF ALBUMINURIA |
|---|
|
TopAbstractIntroductionMEDICAL NUTRITION THERAPY FOR...MNT FOR THE TREATMENT...PUTTING NUTRITION...SUMMARYReferences |
|---|
Research on low-protein diets delaying the progression of renal disease has been controversial. The role of MNT in glucose and blood pressure control is clearly the first priority, but there is some evidence that once albuminuria is present, there may be a beneficial effect on renal function with a reduction of protein to 0.8–1.0 g/kg body wt per day.25 Accurate evaluation and interpretation of protein studies in people with diabetes is difficult because of flaws in design, choice of outcome indicators, retrospective and uncontrolled study designs, unknown state of nephropathy, short-term studies with small numbers of patients, poorly documented adherence to the recommended protein intake, and the limited number of studies in type 2 diabetes. However, despite these flaws, in virtually all reports in subjects with diabetes, renal function improves with a low-protein diet.
A reduction of protein intake in subjects with diabetes and microalbuminuria has been attempted in four studies.25 The achieved protein reduction as measured by urine urea nitrogen ranged from 0.8 to 1.2 g/kg. Even with these small reductions in protein intake, the glomerular filtration rates improved significantly in all four studies, and the albumin excretion rates were reduced significantly in three. In a dose-response analysis, a 0.1 g/kg body wt per day change in intake of animal protein was related to an 11.1% improvement in albuminuria.26
Five studies have been done in subjects with diabetes and macroalbuminuria.25 The achieved protein reduction ranged from 0.7 to 0.9 g/kg. Although beneficial effects from the protein restriction were reported, one study27 raised concern that too low a protein intake may cause malnutrition. Patients in the low-protein group reported lower energy intakes and a significant decrease in body weight compared to the control group.
Therefore, although the majority of the studies report that a reduction of protein to 0.8 g/kg body wt per day may slow progression of overt nephropathy, this must be done in the context of overall adequate energy and nutrient intake. Restricting protein intake to 0.6 g/kg requires the use of special low-protein foods. Of concern is the reported malnourishment with the reduced energy intake accompanying the restricted protein intake. Furthermore, there is no strong evidence supporting the benefit of lowering protein to this extent. In macroalbuminuria, there may be additional benefits in lowering phosphorus intake to 500–1,000 mg/day along with the low-protein diet.28 Patients with nephropathy who are hypertensive and edematous may also benefit from a sodium intake that does not exceed 2,000 mg/day.28
|
PUTTING NUTRITION RECOMMENDATIONS INTO ACTION |
|---|
|
TopAbstractIntroductionMEDICAL NUTRITION THERAPY FOR...MNT FOR THE TREATMENT...PUTTING NUTRITION...SUMMARYReferences |
|---|
How do dietitians and educators assist people with diabetes in putting into action the above recommendations for treating hypertension and, when needed, albuminuria? One way is to focus on the nutrition recommendations by implementing the DASH diet, which corresponds to the American Diabetes Association's A-level evidence-based recommendation, "Foods containing carbohydrate from whole grains, fruits, vegetables, and low-fat milk should be included in a healthy diet."29 Table 4 provides a list of food groups and the number of daily servings to be included in a meal plan of an individual requiring 2,000 cal per day. The number of servings may increase or decrease depending on an individual's energy needs. Individuals also need to heed advice to reduce sodium intake.
|
Fortunately, carbohydrate counting and the DASH diet mesh well. Many of the
serving sizes listed in Table 4
are also the equivalent of one carbohydrate serving.
Table 5 is a sample day's menu
incorporating the DASH diet and carbohydrate counting. The 2,000-calorie menu
contains 1,950 mg of sodium, which is less than the 2,300 mg recommended
for the general public but more than the 1,500 mg found most beneficial in the
DASH-Sodium trial. It is also much less than the 3,500–5,000 mg of daily
sodium that Americans typically average each day, so it is a big step in the
right direction of cutting back on sodium. Even getting down to
2,000–3,000 mg of sodium daily, along with eating more fruits and
vegetables and low-fat dairy foods, would have a significant blood
pressure–lowering effect based on the DASH research data.
|
Fortunately, eating a lot of produce and dairy foods automatically lowers sodium intake. Very little sodium is found in fresh foods; it is processed items that contain the lion's share, contributing up to 80% of the sodium in most diets. Only 20% comes from the salt shaker on the kitchen table.
Counseling patients with diabetes and renal disease requires a dietitian familiar with MNT for both diabetes and renal disease. Table 630 is an example of a diabetes menu incorporating 40 g of protein, 2,000 mg of sodium, low phosphorus, and carbohydrate counting.
|
|
SUMMARY |
|---|
|
TopAbstractIntroductionMEDICAL NUTRITION THERAPY FOR...MNT FOR THE TREATMENT...PUTTING NUTRITION...SUMMARYReferences |
|---|
It is estimated that a population-wide reduction in blood pressure comparable to that seen with the reduced sodium DASH diet would result in a decrease of 17% in the prevalence of hypertension, a 6% reduction in the risk of coronary heart disease, and a 15% reduction in stroke and transient ischemic attacks.31 High blood pressure can be controlled by weight loss in people who are overweight; being physically active; eating more fruits, vegetables, and low-fat dairy foods; choosing foods lower in sodium; limiting alcohol intake; and, if prescribed, taking antihypertensive medications. All but the last also help prevent high blood pressure. If micro- or macroalbuminuria is present, a modest reduction in protein may slow progression of nephropathy.
|
Footnotes |
|---|
Marion J. Franz, MS, RD, CDE, is a nutrition/health consultant at Nutrition Concepts by Franz, in Minneapolis, Minn.
|
References |
|---|
|
TopAbstractIntroductionMEDICAL NUTRITION THERAPY FOR...MNT FOR THE TREATMENT...PUTTING NUTRITION...SUMMARYReferences |
|---|
-
1 Kaplan NM:
Lifestyle modifications for prevention and treatment of hypertension.
J Clin Hypertens 6:716
–719, 2004
2 American Diabetes Association: Nephropathy in diabetes (Position Statement). Diabetes Care 27 (Suppl. 1):S79 –S83, 2004
3 Chobanian AV,
Bakris GL, Black HR, Cushman WC, Green LA, Izzo JL Jr, Jones DW, Maataerson
BJ, Oparil S, Wright JT Jr, Roccella EJ; National Heart, Lung, and Blood
Institute Joint National Committee on Prevention, Detection, Evaluation, and
Treatment of Blood Pressure; National High Blood Pressure Education Program
Coordinating Committee: The Seventh Report of the Joint Committee on
Prevention, Detection, Evaluation, and Treatment of High Blood Pressure.
JAMA 289:2560
–2572, 2003
4 Whitworth JA, Chalmers J: World Health Organization-International Society of Hypertension (WHO/ISH) hypertension guidelines. Clin Exp Hypertens26 : 747–752,2004[Medline]
5 Staessen J, Fagard R, Lijnen P, Amery A: Body weight, sodium intake, and blood pressure. J Hypertens 7 (Suppl.):S19 –S23, 1989
6 The Trials of Hypertension Collaborative Research Group: Effects of weight loss and sodium reduction intervention on blood pressure and hypertension incidence in overweight people with high-normal blood pressure. Arch Intern Med157 : 657–667,1997[Abstract]
7 Appel LJ, Moore
TJ, Obarzanek E, Vollmer WM, Svetky LP, Sacks FM, Bray GA, Vogt TM, Cutler JA,
Windhauser MM, Lin PH, Karanja N, the DASH Collaborative Research Group: A
clinical trial of the effects of dietary pattern on blood pressure.
N Engl J Med 336:1117
–1124, 1997
8 Sacks FM, Svetkey
LP, Vollmer WM, Appel LJ, Bray GA, Harsha D, Obarzanek E, Conlin PR, Miller ER
3rd, Simon-Morton DG, Karanja N, Lin PH, DASH-Soodium Collaborative Research
Group: Effects on blood pressure of reduced dietary sodium intake and Dietary
Approaches to Stop Hypertension (DASH) diet. N Eng J
Med 344:3
–10, 2001
9 He FJ, MacGregor GA: Effect of modest salt reduction on blood pressure: a meta-analysis of randomized trials: implications for public health. J Hum Hypertens 16:761 –770, 2002[Medline]
10 Tuck M, Corry D, Trujillo A: Salt-sensitivity blood pressure and exaggerated vascular reactivity in the hypertension of diabetes mellitus. Am J Med 88:210 –216, 1991
11 Imanishi M,
Yoshioka K, Okumura M, Konishi Y, Okada N, Morikawa T, Sato T, Tanaka S, Fujii
S: Sodium sensitivity related to albuminuria appearing before hypertension in
type 2 patients with diabetes. Diabetes Care24
: 111–116,2001
12 Kelley GA, Kelley
KS: Progressive resistance exercise and resting blood pressure: a
meta-analysis of randomized controlled trials.
Hypertension 35:838
–843, 2000
13 Whelton SP, Chin
A, Xin X, He J: Effect of aerobic exercise on blood pressure: a meta-analysis
of randomized controlled trials. Ann Intern Med136
: 493–503,2002
14 He J, Bazzano LA: Effects of lifestyle modification on treatment and prevention of hypertension. Curr Opin Nephrol Hypertens 9:267 –271, 2000[Medline]
15 Xin X, He J,
Frontini MG, Ogden LG, Motsamai OI, Whelton PK: Effects of alcohol reduction
on blood pressure: a meta-analysis of randomized controlled trials.
Hypertension 38:1112
–1117, 2001
16 Streppel MT,
Arends LR, van `t Veer P, Grobbee DE, Geleijnse JM: Dietary fiber and blood
pressure: a meta-analysis of randomized placebo-controlled trials.
Arch Int Med 165:150
–156, 2005
17 He J, Whelton PK, Klag MJ: Dietary fiber supplementation and blood pressure reduction: meta-analysis of controlled clinical trials [Abstract] Am J Hyertens 9: 74A,1996
18 Whelton PK, He J, Cutler JA, Brancati FL, Appel LJ, Follman D, Klag MJ: Effects of oral potassium on blood pressure: meta-analysis of randomized controlled clinical trials. JAMA 277:1624 –1632, 1997[Abstract]
19 Griffith LE, Guyatt GH, Cook RJ: The influence of dietary and non-dietary calcium supplementation on blood pressure: an updated meta-analysis of randomized controlled trials. Am J Hyertens12 : 84–92,1999
20 Jee SH, Miller ER, Guallar E: The effect of magnesium supplementation on blood pressure: a meta-analysis of randomized clinical trials. Am J Hypertens 15:691 –696, 2002[Medline]
21 Geleijnse JM, Giltay EJ, Grobbee DE: Blood pressure response to fish oil supplementation: meta-regression analysis of randomized trials. J Hypertens 20:1493 –1499, 2002[Medline]
22 Whelton PK, He J,
Appel LJ, Cutler JA, Havas S, Kotchen TA, Roccella EJ, Stout R, Vallbona C,
Winston MC, Karimbakas J, National High Blood Pressure Education Program
Coordinating Committee: Primary prevention of hypertension: clinical and
public health advisory from the National High Blood Pressure Education
Program. JAMA 288:1882
–1888, 2002
23 Miller ER 3rd,
Erlinger TP, Young DR, Jehn M, Charleston J, Rhodes D, Wasan DK, Appel LJ:
Results of the Diet, Exercise, and Weight Loss Intervention Trial (DEW-IT).
Hypertension 40:612
–618, 2002
24 Appel LJ,
Champagne CM, Harsha DW, Cooper LS, Obarzanek E, Elmer PJ, Stevens VJ, Vollmer
WM, Lin PH, Svetkey LP, Stedman SW, Young DR, Writing Group of the PREMIER
Collaborative Research Group: Effects of comprehensive lifestyle modification
on blood pressure control: main results of the PREMIER clinical trial.
JAMA 289:2083
–2093, 2003
25 Franz MJ, Wheeler ML: Nutrition therapy for diabetic nephropathy. Curr Diab Reports 3:412 –417, 2003
26 Pijils LTJ,
deVries H, Donker AJM, van Eijk JTM: The effect of protein restriction on
albuminuria in patients with type 2 diabetes mellitus: a randomized trial.
Nephrol Dial Transplant 14:1445
–1453, 1999
27 Meloni C, Morosetti M, Suraci G, Ennafina MG, Tozzo C, Taccone-Gallucci M, Casciani CU: Severe dietary protein restriction in overt diabetic nephropathy: benefits or risks? J Renal Nutr 12:96 –101, 2002[Medline]
28 Zeller K, Whittaker E, Sullivan L, Raskin P, Jacobson HR: Effect of restricting dietary protein on the progression of renal failure in patients with insulin-dependent diabetes mellitus. N Engl J Med324 : 78–84,1991[Abstract]
29 American Diabetes Association: Nutrition principles and recommendations in diabetes. Diabetes Care 27 (Suppl. 1):S36 –S46, 2004
30 American Association of Kidney Patients: KidneyBeginnings: A Patient's Guide To Living With Reduced Kidney Function. Tampa Fla., American Association of Kidney Patients,2004
31 Greenland P:
Beating high blood pressure with low-sodium DASH. N Engl J
Med 344:53
–55, 2001
CiteULike 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
Related Article:
- Hypertension in Diabetes: Controlling a Critical Comorbid Condition
- Samuel L. Abbate
Diabetes Spectr 2006 19: 17.[Extract] [Full Text] [PDF]
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Diabetes | Diabetes Care | Clinical Diabetes | Diabetes Spectrum |