Hypertension (HTN)
• The most prevalent chronic disorder
– Affects 72 million people: 31% of adults
– 81% are aware they have it; 73% are being treated
• Defined: Sustained elevation of resting systolic (BP >
140 mm Hg), diastolic BP (> 90 mm Hg) or both.
• Complications usually observed when:
– Systolic > 140 mm Hg
– Diastolic > 90 mm Hg
Seventh Report of the Joint National Committee on Prevention, Detection,
Evaluation, and Treatment of High Blood Pressure (JNC 7) JAMA 289: 2560, 2003
http://www.medicalentrytest.com
Objectives: Hypertension (HTN)
• Write the physiological formula that describes blood
pressure (BP)
• Define pulse pressure
• Describe the classifications of blood pressure
• Identify follow-up recommendations for each classification of
BP
• List the non-behavioral and behavioral risk factors for
hypertension.
• Describe the main complications of uncontrolled
hypertension.
• List at least three components of the DASH diet
• Identify foods high in sodium, calcium, and potassium.
• Describe recommended methods for reducing high blood
pressure.
Overview of Hypertension (HTN)
• Most prevalent chronic disease
–
–
–
–
–
–
31% of population (65 million with HTN; 45 m – pre-HTN)
41% of blacks (44% in black women)
50% of population > 60ys
90% of normotensive at age 55 will develop HTN
Contributes to up to 75% of all strokes and heart attacks
2-3 times more common if taking OCA
• Asymptomatic
– Dizziness, flushed face, headache, fatigue, and
nervousness are not related to hypertension
Circulation 2008;117;e25-e146 -- http://circ.ahajournals.org/cgi/content/full/117/4/e25
Prevalence of HBP in adults ≥20 years of age by age and sex
(NHANES: 2005–2008).
90
78.5
80
69.3
70
Percent of Population
64.0
60
54.0
66.7
53.3
50
37.1
40
30
35.2
25.1
19.0
20
11.1
10
6.8
0
20-34
35-44
45-54
55-64
65-74
75+
Age
Male
Female
Source: NCHS and NHLBI. Hypertension is defined as SBP 140 mm Hg or DBP 90 mmHg, taking antihypertensive medication, or being told twice by a physician or
other professional that one has hypertension.
Roger VL et al. Published online in Circulation Dec. 15, 2010
Age-Adjusted Prevalence Trends for HBP in Adults, ≥20 years of age by
race/ethnicity, sex and survey
(NHANES:1988-1994, 1999-2004 and 2005-2008).
50
42.9
45
40.2
38.6
40
37.5
Percent of Population
35
41.5
38.2
30.5
28.3
28.2
30
25
26.9
27.7
25.6
26.8
25.7
24.6
22.9
25.0
25.0
20
15
10
5
0
NH White Men
NH White Women
NH Black Men
1988-1994
NH Black Women
1999-2004
Mexican
Mexican
American Men American Women
2005-2008
Source: NCHS and NHLBI. NH indicates non-Hispanic.
Roger VL et al. Published online in Circulation Dec. 15, 2010
Blood Pressure Tracking
BP
AGE
What is the Etiology?
• HTN is described as either primary or secondary
• Primary – 85-95% of cases (essential):
– No known cause
– Genetics contribute 30 – 50%
• HTN nonexistent in hunter-gatherer populations
– Physical activity, low fat/sodium intake, K-rich diet
– Sodium retention increases blood volume
– Vascular stiffness (with age) increases pressure
– Weight gain increases sympathetic activity
• Insulin resistance increases sympathetic stimulation
• Also increases sodium retention
• Secondary
– Due to renal disease, connective tissue disorders,
hyperthyroidism, NSAIDS, licorice, steroid use
Blood Pressure: Pathophysiology
• BP ≈ Q x TPR
– Q = cardiac output (4-8 L/min)
• Q = HR x SV (50 – 100 mL)
– TPR = total peripheral vascular resistance
• Abnormal Na+ transport
• Sympathetic nervous stimulation – high
resting heart rate may indicate this
• Vasodilator deficiency rather than excess
vasoconstrictor
*Circulation, 1999; 100: 354-360
Diagnosis
On separate occasions of at least two readings: average of seated
and after standing for > 2 min on 3 separate days.
•
•
•
•
Category
Normal
Prehypertension
Hypertension, Stage 1
Hypertension, Stage 2
•
•
•
•
SBP
<120
and
120-139 or
140-159 or
>160
or
Resources:
http://www.nhlbi.nih.gov/guidelines/hypertension/index.htm
Hypertension. 2005;45:142-161.
* http://www.guideline.gov/summary/summary.aspx?doc_id=8326
DBP
<80
80-89
90-99
>100
What recommendations
should we provide?
•
•
•
•
Initial BP:
Normal
Prehypertension
Hypertension, Stage 1
Hypertension, Stage 2
•
•
•
•
Recommendation:
Check in 2 yrs
Recheck in 1 yr
Confirm in 1 month
Evaluate immediately or
within 1 week
http://www.nhlbi.nih.gov/guidelines/hypertension/index.htm
Types of Hypertension
– Primary (essential) – no identified cause
• 90% of all cases
– Secondary – has cause (reversible potential)
• Kidney dz, sleep apnea
• Medications (corticosteroids, NSAIDS, OCAs)
• Alcohol, smoking, caffeine, stress
– Isolated Systolic Hypertension
• > 160 mm HG (atherosclerosis)
– Pregnancy Induced Hypertension
– White Coat Hypertension – (a possible risk factor)
What are the Risk Factors
for HTN?
• Advanced age – lifetime risk is 90%
– > 45 for men; 55 for women
• Gender – men > women until age 55 then more
common in women
• Race
– African American highest in world (41%)
– Hispanic, Caucasian, Native Am same (24%)
– Asian/Pacific Island (9.7%)
What are the Risk Factors for HTN
•
•
•
•
•
•
•
•
•
•
Obese (BMI > 30)
High sodium intake & low potassium
Diabetes
Alcohol intake
Physical inactivity
Prehypertension
Stress
Low education levels
Sleep apnea
Family history
Risk Factors (HTN)
• Weight
– Obesity (33% of hypertensives are overweight)
• Increased visceral fat
– Thin with HTN at higher risk of MI & stroke than
obese with HTN
– Low birth weight associated with obesity & HTN
http://staciel.hubpages.com
Risk Factors for HTN
• Sodium Retention (salt sensitivity)
– Sodium  blood volume   BP
– Assume all are salt sensitive
• Diabetes and Insulin Resistance
– Occurs in thin and overweight diabetics
http://www.hcgdiet.com
Salt Sensitivity
• Not feasible to test in most people
• Factors associated with salt sensitivity:
– Female
– Age (increasing age increases sensitivity)
– Obesity (abdominal obesity)
– Alcoholism
– African-American origin
– Level of blood pressure
• higher pressure = more sensitive
– Diabetes
– Positive family history
http://foodandhealth.com
Complications*
• Stroke (or TIA’s)
– 10x normal risk in hypertensive
• Coronary Heart Disease / MI / Sudden Death
– ½ of those with MI have HTN
– Each 20/10 mmHg increase doubles MI risk
• Heart Failure
– Muscles thicken (left ventricular hypertrophy)
– HTN factor in 75-90% of HF
*Complication: a secondary disease or condition that develops
as a result of the primary illness or from independent causes
More HTN Complications
•
•
•
•
•
Atrial fibrillation
Aneurysms
Kidney Disease
Retinopathy
Bone loss
– HTN increases calcium loss
mayfieldclinic.com
• Sexual dysfunction
• Preeclampsia – complicates 10% of pregnancies
• Cognitive dysfunction & dementia – short term
memory loss & mental decline
What about Pulse Pressure?
•
•
•
•
•
•
•
•
•
•
•
PP = SBP – DBP
Pulse pressure* – change in BP when heart contracts
Indicates stiffness in the aorta
Indicates stretching of arteries and eventual rigidity
Increases risk for aneurysms
Mean Arterial Pressure = Diastolic + (1/3 x PP)
BP of 170/100 is better than 170/80
Linked with CVD mortality
< 50 mmHg = normal
> 60 – abnormal
< 25 – heart failure?
*Hypertension, 1999;34:372-374
Mean Arterial Pressure (MAP)
• Average arterial pressure - more accurate than SBP DBP
• Better indicator of arterial perfusion of tissue/organs
• Low = decreased perfusion. High = increased cardiac
workload
• Vasoconstriction increases MAP, vasodilation
decreases
• Normal MAP = 70 – 100 mm Hg
• A risk factor for CVD
• Formula
– MAP = 1/3 (PP) + DBP
Non-Pharmacological Treatment
• Weight loss and exercise
– Wt loss to a BMI of 18.5 – 24.9
– Exercise: 30 min/day most days
• Smoking cessation
• Diet: increased fruits and vegetables, decreased salt,
limit alcohol
–
–
–
–
DASH diet
Rich in fruit and veges, reduced saturated fat
Include fish and/or omega 3 fatty acid (2x/wk)
Reduce sodium intake to 1500 mg/day
• 1/2 teaspoon salt = 1,200 mg sodium
– Alcohol < 1 oz/day in men and < 0.5 oz/day in women
National Heart, Lung, and Blood Institute, National Institutes of Health. The Seventh Report of the Joint National Committee
on Prevention,Detection, Evaluation, and Treatment of High Blood Pressure — Complete Report. National Heart, Lung, and
Blood Institute, National Institutes of Health. NIH Publication No. 04-5230, 2004
The Salty
Six
www.heart.org
List components of the
DASH Diet
•
•
•
•
•
•
Avoid saturated fat
Select monounsaturated oil (olive, canola)
Choose whole grains over white flour
Choose fresh fruits and vegetables every day
Include nuts, seeds and legumes every day
Include calcium-rich dairy products (low or no
fat)
http://www.nhlbi.nih.gov/health/public/heart/hbp/dash/
Medications for HTN
• Diuretics
– promote water loss, remove potassium
– Side effects: dizziness, fatigue, impotence, orthohypo, nausea, constipation, dry mouth
– May worsen type 2 diabetes in overweight patients
• Beta blockers
– block actions of adrenalin
– Numerous side effects
• ACE Inhibitors
– block action of angiotensin (a vasoconstrictor)
• Calcium channel blockers
– dilate peripheral arteries – decrease TPR
References
•
Chobanian AV et al. JAMA. 2003;289:2560-2572
•
Sacks FM, Svetkey LP, Vollmer WM, et al. Effects on blood pressure of reduced dietary sodium and the
Dietary Approaches to Stop Hypertension(DASH) diet. DASH-Sodium Collaborative Research Group. N
Eng J Med. 2001;344:3-10.
•
Eckel RH, Jakicic JM, Ard JD, Hubbard VS, de Jesus JM, Lee I-M, Lichtenstein AH, Loria CM, Millen BE,
Houston Miller N, Nonas CA, Sacks FM, Smith SC Jr, Svetkey LP, Wadden TW, Yanovski SZ. 2013
AHA/ACC guideline on lifestyle management to reduce cardiovascular risk: a report of the American
College of Cardiology/American Heart Association Task Force on Practice Guidelines. Circulation.
2013:November 12, 2103, 10.1161/01.cir.0000437740.48606.d1