Transcript JNC 7 Organizational Structure

Hypertension: Medical Management
and Nutritional Approaches
Hypertension
 Persistently high arterial blood
pressure
 Systolic blood pressure above 140
mm Hg and/or diastolic blood
pressure above 90 mm Hg
 Normotensive = 120/80 mm Hg
 Prehypertensive = 120–139/80-89
mm Hg
 Stage 1 hypertension = 140–159/9099 mm Hg
 Stage 2 hypertension = >160/>100
mm Hg
Prevalence and Incidence
29% of adult US population
Related to body mass index
High prevalence in African Americans
5% of pediatric population; prevalence increases
with age
 Strong positive relationship between blood pressure
and risk of CVD events
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
Pathophysiology
 Blood pressure is a function of cardiac output
multiplied by peripheral resistance
 Affected by diameter of blood vessel
 Atherosclerosis decreases diameter, increases blood
pressure
 Drug therapy increases diameter, lowers blood
pressure
Circulatory Systems in the Body
1. Coronary—supplies blood to heart
muscle (can form collateral
circulation)
2. Cerebral—supplies blood to head
3. Splanchnic—supplies blood to
abdomen (exercise removes blood
and food attracts blood to this area)
4. Pulmonary—supplies blood to lungs
(O2 and CO2 exchange)
Measures of Heart Function
1. Beats or pulse
2. BP systolic and diastolic
3. ECG
Determinants of Blood Pressure
1. Blood volume
2. Vascular resistance to pressure
3. Heart stroke volume
Cardiac Output
■ Amount of
blood pumped by heart (vol/min)
■ Stroke volume times heart rate
Vascular Resistance
■ Viscosity of blood
■ Width of vessels—(constriction or
dilation)—controlled by muscle tone in
vessel walls
Regulation of Blood Pressure
Sympathetic nervous system (SNS)—responds
immediately; baroreceptors monitor BP
Vasomotor center in brain
SNS innervated tissues contract or dilate vascular
bed
2. Renin-angiotensin system—retains Na and H2O to
increase blood volume; constricts blood vessels;
increases aldosterone
3. Kidneys—respond to renin-angiotensin system;
aldosterone and antidiuretic hormone (ADH) are sent
out as needed
1.
Homeostatic Control of
Blood Pressure
 Short term
—Sympathetic nervous system
—Vasoconstriction
—Vasodilation
 Long term
—Fluid volume
—Renin-angiotensin system
Hypertension
1. 90% HTN is essential HTN (cause unknown;
perhaps prenatal impacts?)
2. 10% HTN is secondary to other diseases
3. HTN is a risk factor for MI, CVA, renal failure
Renin-Angiotensin Cascade
Redrawn from Guyton AC: Textbook of medical physiology, ed 8, Philadelphia, 1991, WB Saunders.
Causes of Hypertension
Algorithm content developed by John Anderson, PhD, and Sanford C. Garner, PhD, 2000.
Risk Factors for Developing
Hypertension
(Adapted from National High Blood Pressure Education Program Working Group report on primary prevention of hypertension.
Arch Intern Med 153:186, 1993. Copyright 1993, American Medical Association. Reprinted with permission.)
Risk Stratification in Patients with
Hypertension
(From The Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. sixth report
(JNC VI). Arch Intern Med 157:2413, 1997.)
Uncontrolled Hypertension
Leads to increased
 Workload on heart
 Damage to arteries
 Atherosclerosis
 Coronary heart disease esp. CHF
 Strokes
 Transient ischemic attacks (TIAs)
 Kidney damage
 Microvascular hemorrhages in brain and eye
The DASH Diet Trials
 Randomized feeding trial comparing effects of 3 diet
patterns: control, high fruits/vegetables, and high
fruits/vegetables/whole grains/lowfat dairy (DASH diet)
 DASH diet high in potassium, magnesium, calcium,
fiber and low in fat, saturated fat, and cholesterol
 DASH diet significantly lowered BP in all groups, but
especially in African-Americans
Effects of Diet on BP (DASH Trial)
OMNI-Heart Feeding Study
 Subjects were 164 adults with prehypertension or stage
1 hypertension, 55% African American, mean BMI 30
 Compared effect of 3 healthy diet patterns—all reduced
in saturated fat and cholesterol, rich in fruits,
vegetables, potassium, and other minerals at
recommended levels
 Diets were high CHO (58% of calories), high in protein,
high in unsaturated fat
 Researchers provided all the food for the study
 Each feeding period lasted 6 weeks and body weight
was kept constant.
http://www.medscape.com/viewarticle/523041
OMNI-Heart Diets
CHO Diet
PRO DIET
UNSAT FAT
DIET
CHO % kcal
58
48
48
PRO % kcal
15
25
15
FAT % kcal
27
27
37
MFA % kcal
13
13
21
PUFA % kcal
8
8
10
SFA % kcal
6
6
6
OMNI-HEART Results
 Results: All 3 diets lowered systolic blood pressure
 Substitution of protein or mfa for CHO lowered blood
pressure further; Compared with the carbohydrate diet,
estimated 10-year coronary heart disease risk was
lower and similar on the protein and unsaturated fat
diets
http://www.medscape.com/viewarticle/523041
OMNI-Heart Feeding Study
National Heart, Lung, and Blood Institute
National High Blood Pressure Education Program
U.S. Department of
Health and Human
Services
National Institutes
of Health
National Heart, Lung,
and Blood Institute
The Seventh Report of the
Joint National Committee on
Prevention, Detection,
Evaluation, and Treatment of
High Blood Pressure (JNC 7)
Express—Succinct evidence-based
recommendations. Published in JAMA May
21, 2003, and as a Government Printing Office
publication.
New Features and Key Messages
For persons over age 50, SBP is a more important
than DBP as CVD risk factor.
 Persons who are normotensive at age 55 have a 90%
lifetime risk for developing HTN.
 Those with SBP 120–139 mmHg or DBP 80–89 mmHg
should be considered prehypertensive who require
health-promoting lifestyle modifications to prevent
CVD.
New Features and Key Messages
(Continued)
 Thiazide-type diuretics should be initial drug therapy for
most, either alone or combined with other drug classes.
 Certain high-risk conditions are compelling indications for
other drug classes.
 Most patients will require two or more antihypertensive
drugs to achieve goal BP.
 If BP is >20/10 mmHg above goal, initiate therapy with two
agents, one usually should be a thiazide-type diuretic.
Blood Pressure Classification
BP Classification
SBP mmHg
DBP mmHg
Normal
<120
and
<80
Prehypertension
120–139
or
80–89
Stage 1 Hypertension
140–159
or
90–99
Stage 2 Hypertension
>160
or
>100
CVD Risk
 HTN prevalence ~ 50 million people in the United States.
 The BP relationship to risk of CVD is continuous, consistent,
and independent of other risk factors.
 Each increment of 20/10 mmHg doubles the risk of CVD
across the entire BP range starting from 115/75 mmHg.
 Prehypertension signals the need for increased education to
reduce BP in order to prevent hypertension.
Benefits of Lowering BP
Average Percent Reduction
Stroke incidence
35–40%
Myocardial infarction
20–25%
Heart failure
50%
BP Control Rates
Trends in awareness, treatment, and control of high
blood pressure in adults ages 18–74
National Health and Nutrition Examination Survey, Percent
II
1976–80
II
(Phase 1)
1988–91
II
(Phase 2)
1991–94
1999–2000
Awareness
51
73
68
70
Treatment
31
55
54
59
Control
10
29
27
34
Sources: Unpublished data for 1999–2000 computed by M. Wolz, National Heart, Lung, and Blood Institute; JNC 6.
BP Measurement Techniques
Method
Brief Description
In-office
Two readings, 5 minutes apart, sitting in
chair. Confirm elevated reading in
contralateral arm.
Ambulatory BP monitoring
Indicated for evaluation of “white-coat” HTN.
Absence of 10–20% BP decrease during
sleep may indicate increased CVD risk.
Provides information on response to therapy.
May help improve adherence to therapy and
evaluate “white-coat” HTN.
Self-measurement
CVD Risk Factors
 Hypertension*
 Microalbuminuria or
estimated GFR <60
 Cigarette smoking
ml/min
2
 Obesity* (BMI >30 kg/m )
 Age (older than 55 for
Physical inactivity
men, 65 for women)
 Dyslipidemia*
 Family history of
premature CVD (men
 Diabetes mellitus*
under age 55 or
women under age 65)
*Components of the metabolic syndrome.
Target Organ Damage
 Heart
• Left ventricular hypertrophy
• Angina or prior myocardial infarction
• Prior coronary revascularization
• Heart failure
 Brain
• Stroke or transient ischemic attack
 Chronic kidney disease
 Peripheral arterial disease
 Retinopathy
Goals of Therapy
Reduce CVD and renal morbidity and mortality.
 Treat to BP <140/90 mmHg or BP <130/80 mmHg in
patients
with diabetes or chronic kidney disease.
 Achieve SBP goal especially in persons >50 years of
age.
Lifestyle Modification
Modification
*Weight reduction
Approximate SBP reduction
(range)
5–20 mmHg/10 kg weight loss
*Adopt DASH eating plan
8–14 mmHg
*Dietary sodium reduction
2–8 mmHg
Physical activity
4–9 mmHg
*Moderation of alcohol
consumption
2–4 mmHg
*medical nutrition therapy interventions
Classification of
Antihypertensive Drugs
 Diuretics
—Thiazides
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


—Loop diuretics
—Potassium-sparing diuretics
Beta blockers (BB)
Angiotensin II receptor blockers (ARBs)
Alpha-beta blockers
Alpha1 receptor blockers
ACE inhibitors (angiotensin converting enzyme)
Calcium antagonists
Direct vasodilators
Algorithm for Treatment of Hypertension
Lifestyle Modifications
Not at Goal Blood Pressure (<140/90 mmHg)
(<130/80 mmHg for those with diabetes or chronic kidney disease)
Initial Drug Choices
Without Compelling
Indications
With Compelling
Indications
Stage 1 Hypertension
Stage 2 Hypertension
(SBP 140–159 or DBP 90–99 mmHg)
Thiazide-type diuretics for most.
May consider ACEI, ARB, BB, CCB,
or combination.
(SBP >160 or DBP >100 mmHg)
2-drug combination for most (usually
thiazide-type diuretic and
ACEI, or ARB, or BB, or CCB)
Not at Goal
Blood Pressure
Optimize dosages or add additional drugs
until goal blood pressure is achieved.
Consider consultation with hypertension specialist.
Drug(s) for the compelling
indications
Other antihypertensive drugs
(diuretics, ACEI, ARB, BB, CCB)
as needed.
Compelling Indications
 These are reasons for using a particular class of
medications
 For example, patients with diabetes, kidney damage,
and high blood pressure should begin treatment with
ACE inhibitors.
 Heart attack (in conjunction with hypertension) is a
compelling indication for the prescription of betablockers and, in certain instances, ACE inhibitors
 Heart failure should first be treated with ACE inhibitors
and diuretics.
Classification and Management
of BP for adults
BP
classification
Normal
SBP*
mmHg
DBP*
mmHg
Lifestyle
modification
<120
and <80
Encourage
Initial drug therapy
Without compelling
indication
Prehypertension 120–139 or 80–89
Yes
No antihypertensive drug
indicated.
Stage 1
Hypertension
Yes
Thiazide-type diuretics for
most. May consider ACEI,
ARB, BB, CCB, or
combination.
Yes
Two-drug combination for
most† (usually thiazide-type
diuretic and ACEI or ARB or
BB or CCB).
Stage 2
Hypertension
140–159 or 90–99
>160
or >100
*Treatment determined by highest BP category.
†Initial combined therapy should be used cautiously in those at risk for orthostatic hypotension.
‡Treat patients with chronic kidney disease or diabetes to BP goal of <130/80 mmHg.
With compelling
indications
Drug(s) for compelling
indications. ‡
Drug(s) for the
compelling
indications.‡
Other antihypertensive
drugs (diuretics, ACEI,
ARB, BB, CCB) as
needed.
Minority Populations
 In general, treatment similar for all demographic groups.
 Socioeconomic factors and lifestyle important barriers to BP control.
 Prevalence, severity of HTN increased in African Americans.
 African Americans demonstrate somewhat reduced BP responses to
monotherapy with BBs, ACEIs, or ARBs compared to diuretics or
CCBs.
 These differences usually eliminated by adding adequate doses of a
diuretic.
Children and Adolescents
 HTN defined as BP—95th percentile or greater, adjusted for age,
height, and gender.
 Use lifestyle interventions first, then drug therapy for higher levels of
BP or if insufficient response to lifestyle modifications.
 Drug choices similar in children and adults, but effective doses are
often smaller.
 Uncomplicated HTN not a reason to restrict physical activity.
Web site
www.nhlbi.nih.gov/
Your Guide to Lowering
Blood Pressure
Reference Card
Lifestyle Modifications
 Sodium: not more than 2.4 grams sodium/day
 Activity: activity like brisk walking 30 minutes/day most
days of the week
 Alcohol: not more than 1 drink a day for women; 2
drinks a day for men
 DASH diet: low in sodium, high in potassium, calcium,
cholesterol, saturated fat
 Weight: weight loss of as little as 10 lb can prevent or
treat high blood pressure
Weight Management
 Risk of developing high blood pressure is 2-6 times
higher in overweight than normal weight persons
 20-30% of the hypertension in the US is attributable to
excess weight
 In Framingham, weight increase of 10% predicted rise
in blood pressure of 7 mm/hg
 Weight gain during adult life is responsible for much of
the rise in blood pressure seen with aging
Weight Management
 Excess body weight may increase blood pressure
through increased insulin resistance and
hyperinsulinemia, activation of the sympathetic nervous
and renin-angiotensin systems, and changes in the
kidney
 Weight loss lowers vascular resistance, total blood
volume, cardiac output, and sympathetic nervous
system activity; improves insulin resistance
 Weight loss in an overweight person is the single most
effective lifestyle intervention to reduce blood pressure
Weight Management
 In the Trial of Antihypertensive Intervention and
Management, goal for energy intake to facilitate weight
loss was 25 kcals/kg minus 500 to 1000 kcal daily to
produce a .5 to 1 kg weight loss/week to achieve total
weight loss of 4.5 kg.
Wylie-Rosett et al, 1993
Sodium and Hypertension
Relationship between sodium and hypertension is stronger
in
 Older people
 Those with a family history of hypertension
 Those with higher blood pressures at baseline
 30-50% of hypertensives and 15-25% of normotensives
are salt sensitive
 Salt sensitivity more common in black race, obesity,
advanced age, diabetes, renal dysfunction, use of
cyclosporine
Sodium and Hypertension
 Addition of a sodium restriction to a DASH diet lowers
SBP 3 mmHg and DBP 2 mmHg
 This reduction is associated with a 17% reduction in
prevalence of hypertension, 6% reduction in CHD, 15%
reduction in stroke and TIA
Salt Restriction
 Recommendation is for moderate salt restriction (6
grams salt, 100 mEq or 2400 mg Na daily)
 Salt is the issue, because chloride ion with sodium
raises blood pressure
 May normalize blood pressure in Stage 1 hypertension
Levels of Na Restriction
g Na
4
2-3
mEq Na
174
87-130
1
0.5
43
22
Description
No added salt
Mild to moderate
restriction
Strict sodium restriction
Severe sodium restriction
Alcohol and Hypertension
 5-7% of hypertension is due to alcohol
consumption
 3 drinks per day is the threshold for raising
blood pressure; associated with a 3 mmHg
increase
Physical Activity and Hypertension
 Less active persons are 30-50% more likely to develop
hypertension than active persons
 Medium to high levels of activity protective against
stroke (Framingham)
 Walking reduces blood pressure in adults by an
average of 2%
 In a meta-analysis of 54 randomized trials, walking
reduced blood pressure an average of 4 mmHg,
irrespective of weight change
Potassium
 In population studies, potassium intake and blood
pressure are inversely related
 Sodium/potassium ratio is important
 Sodium/potassium ratio of 1:1 a 3.4 mmHg decrease in
systolic BP is predicted
 High potassium intake inversely related to stroke
Other Factors
 Calcium, Magnesium, and Lipids: role still unclear
 DASH diet high in lowfat dairy products
Response to Dietary Rx
 Salt sensitive respond well to sodium restriction
 Most respond to increased potassium in diet.
• 1.1 to 3.3 g Na is safe
• 1.9 to 5.6 g K is recommended to achieve ratio Na:K of
1, which is goal
 If taking a potassium-wasting diuretic drug, increased
potassium in diet is essential.
 Most respond to increased calcium (at least the RDA)—use
the DASH diet protocol
DASH Diet
 Works within 14 days
 Lowers BP quite well
 Includes more potassium, calcium,
other nutrients
DASH Fact Sheet
www.nhlbi.nih.gov/heal
th/public/heart/hbp/dash/
new_dash.pdf
DASH Diet —cont’d
 Pattern
—7-8 whole grains
—4-5 vegetables
—4-5 fruits
—2-3 low-fat or fat-free dairy products
—6 oz or less meat/poultry/fish
—4-5 servings nuts, beans, or legumes/week
—2-3 servings fat (total kcal = 27% fat)
DASH Diet Patterns for
Different Calorie Levels
Kcals
Grain
Veg
Fruit
Dairy
Meat/ Nuts/
Fats/
Pro
Legume oils
1600
6
4
4
2
1
.5
1
2000
8
5
5
3
2
1
2
2600
10
5
5
3
2
1
2
3100
13
6
6
4
2
1
3
Sodium
 Processed and restaurant foods provide 80% of sodium
intake
 Read labels; sodium content of different brands varies
 10% added in cooking at home and at table; 10% naturally
occurring
 Americans consume ~4,000 mg/day; 2005 Dietary Guidelines
for Americans recommend <2,300 mg/day; those with
hypertension, African Americans and middle-aged and elderly
should consume <1,500 mg/day
Food Label Terms




Sodium free, no sodium = <5 mg/serving
Very low sodium = <35 mg/serving and per 100 g food
Low sodium = <140 mg/serving and per 100 g food
Reduced sodium = 50% less than comparison food
Salt Substitutes
 Composition: KCl, CaCl, Al-Cl
 KCl can provide extra potassium for those taking
diuretics
 KCl can be harmful if patient has renal insufficiency
 “Lite” salt contains sodium
 Some spices and herbs are low in sodium
 Others are high in sodium
Classification of
Antihypertensive Drugs
 Diuretics
—Thiazides







—Loop diuretics
—Potassium-sparing diuretics
Beta blockers (BB)
Angiotensin II receptor blockers (ARBs)
Alpha-beta blockers
Alpha1 receptor blockers
ACE inhibitors (angiotensin converting enzyme)
Calcium antagonists
Direct vasodilators
http://www.nhlbi.nih.gov/hbp/treat/bpd_type.htm
Lifestyle Modifications for Prevention of
Hypertension
 Lose weight if overweight
 Limit alcohol
 Increase physical activity
 Decrease sodium intake
 Keep potassium intake at adequate levels
 Take in adequate amounts of calcium and magnesium
 Decrease intake of saturated fat and cholesterol
 Stop smoking
Summary
 Lifestyle modifications for prevention of hypertension—
quite effective!
 Management of hypertension—very important to reduce
risk of heart attack or stroke