Transcript Blood Pressure Classification

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Review Of Management Of Hypertension
By
Professor
Dr Intekhab Alam
Department of Medicine
Lady Reading Hospital,
Peshawar
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Management of Hypertension
Lecture Objectives
• Define Hypertension (HTN)
• Learn how to measure blood pressure
• Understand initial clinical evaluation
• Identify causes of secondary HTN
• Describe lifestyle modifications that lower blood
pressure
• Select appropriate anti-HTN medications
• Provide appropriate follow-up care
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What is Blood Pressure?
The primary reason most of us are awake
and breathing at this very moment in this
lecture!
BP = CO x TPR
(CO = HR x SV)
– Stroke volume – affected by contractility and venous return
– TPR is regulated by
Norepinephrine, Epinephrine, Angiotensin II.
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Hypertension Defined
“Hypertension (HTN)
is defined as
sustained abnormal
elevation of the
arterial blood
pressure.”
(Brashers, 2006, p.1).
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Hypertension
“It is an abnormal and persistent elevation of BP.”
BP limits are different in children and pregnancy.
BP goal is different if you have diabetes or chronic
kidney disease.
Primary (“essential”) 95% of cases.
Secondary 5% of cases.
Starting at 115/75 mmHg, CVD risk doubles with
each increment of 20/10 mmHg throughout the BP
range.
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JNC-7 Classification
BP Classification
SBP (mmHg)
Normal
< 120
Prehypertension
DBP (mmHg)
and
< 80
120-139
or
80-89
Stage I hypertension
140-159
or
90-99
Stage II hypertension
> 160
or
> 100
http://hin.nhlbi.nih.gov/nhbpep_slds/menu.htm
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Diagnosis of HTN
Repeated abnormal elevation of BP using
proper technique/cuff on 3 separate occasions
over at least 6 weeks
A single blood pressure >200/120
Keep in mind:
– Risk factors
– Evidence of end-organ disease
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Epidemiology !
The most common primary diagnosis in the United States, 50 million
American affected.
Only 70% are aware they have HTN
Of those aware of their HTN, only 50% are being treated.
Only 25% of all hypertensive patients have their BP under control
In the year 2000, 16·7 million people died from cardiovascular
disease, accounting for 30·3% of all deaths worldwide
HTN is a risk factor for coronary artery disease (CAD), congestive
heart failure (CHF), stroke, and renal failure
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Prevalence of Hypertension in South Asia
More than half of the cardiovascular deaths take place in
developing countries.
South Asia (Pakistan, India, Bangladesh, Nepal, and Sri
Lanka) represents more than a quarter of the developing
world, and is likely to be strongly affected by the
increase in cardiovascular disease, for several reasons.
First, people from south Asia are known to have a high
coronary risk; this tendency has been well recorded in
studies of expatriate south Asians and has also been
shown in native settings.
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Prevalence of Hypertension in South Asia
Sex
Men
Pakistan 1
India 2,3
Bangladesh 4
Nepal 6
Sri Lanka 5
17%
36.4%
9.8
..
17%
…
37.5%
15.6%
..
..
15-30 Years
Women
15-30 Years
• Hypertension classified according to WHO Criteria
References: 1. Pakistan Medical Research Council. National Health Survey of Pakistan 1990-94: health profile of the people of Pakistan.
Islamabad: Network publication service, 1998. 2. Gupta R, Gupta VP, Sarna M, et al. Prevalence of coronary heart disease and risk factors in an
urban Indian population: Jaipur Heart Watch-2. Indian Heart J 2002; 54: 59-66. 3.Fernandes VL, Kottke TE, Nicholas JJ. Tobacco consumption and
coronary artery disease. In: Rao GHR, Kakkar VV, eds. Coronary artery disease in South Asians., New Dehli: Jaypee Brothers, 2001: 147-64. 4.
Zaman MM, Yoshiike N, Rouf MA, et al. Cardiovascular risk factors: distribution and prevalence in a rural population of Bangladesh. J Cardiovasc
Risk 2001; 5. 103-08. 5.Mendis S, Ekanayake EM. Prevalence of coronary heart disease and its risk factors in middle aged males in a defined
population in central Sri Lanka. Int J Cardiol 1994; 46: 135-42. 6.Pandey MR, Neupane RP, Gautam A. Epidemiological study of tobacco smoking
among adults in a rural community of the hill region of Nepal with special reference to attitudes and beliefs. Int J Cardiol 1988; 17: 535-41.
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The CVD Situation in Pakistan
Pakistan's Hypertension Statistics (NHS)
Hypertension is the most common cardiovascular disease in Pakistan.
There are an estimated 12 million hypertensives in the country.
Hypertension affects one in three individuals over the age of 45 years in
Pakistan.
Only 3% of the hypertensive population in Pakistan is adequately
controlled.
(The National Health Survey of Pakistan, jointly conducted by the Pakistan Medical Research Council in collaboration with the Federal
Bureau of statistics, Pakistan and the Department of Health ad Human Services, Washington, USA )
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Historical Trends in HTN
National Health and Nutrition Examination Survey
Trends in awareness, treatment, and control of high blood
pressure in adults ages 18-74
1976-1980
1988-1991
1991-1994
1994-2000
Awareness
51%
73%
68%
70%
Treatment
31%
55%
54%
59%
Control
10%
29%
27%
34%
SBP < 140 mmHg and DBP < 90 mmHg
http://hin.nhlbi.nih.gov/nhbpep_slds/menu.htm
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Benefits of Lowering BP
Sustaining a 12 mmHg reduction in SBP over 10 years
will prevent one death for every 11 patients treated with
Stage I HTN with additional CVD risk factors
Why to treat HTN?
“The relationship between BP and CVD is positive and continuous.”
–
–
–
–
–
35-40%  in stroke morbidity and mortality
20-25%  CAD events
21%  vascular mortality
52%  in CHF
35%  in LVH
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BP Measurement Techniques
Method
Brief Description
In-office
Two readings, 5 minutes apart, sitting in
chair. Confirm elevated reading in contra
lateral arm.
Ambulatory BP
monitoring
Indicated for evaluation of “white-coat”
HTN. Absence of 10–20% BP decrease
during sleep may indicate increased CVD
risk.
Self-measurement
Provides information on response to
therapy. May help improve adherence to
therapy and evaluate “white-coat” HTN.
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Patient Evaluation
Evaluation of patients with documented HTN has
three objectives:
1. Assess lifestyle and identify other CV risk factors or
concomitant disorders that affects prognosis and guides
treatment.
2. Reveal identifiable causes of high BP.
3. Assess the presence or absence of target organ damage
and CVD.
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Patient Evaluation
Assess lifestyle and identify other CV risk factors or
concomitant disorders
Hypertension
Smoking
Obesity
Physical inactivity
Dyslipidemia
Diabetes
Microalbuminuria or est
GFR < 60 ml/min
Age
– Males > 55 yrs
– Females > 65 yrs
Family history of CVD
– Males < 55 yrs
– Females < 65 yrs
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Identifiable Causes of Hypertension
 Sleep apnea
 Drug-induced or related causes
 Chronic kidney disease
 Primary aldosteronism
 Renovascular disease
 Chronic steroid therapy and Cushing’s syndrome
 Pheochromocytoma
 Coarctation of the aorta
 Thyroid or parathyroid disease
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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
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Laboratory Tests
Routine Tests
Electrocardiogram (Look for LVH, CAD, arrhythmia)
Urinalysis (Look for protein/blood)
Blood glucose, and hematocrit
Serum potassium, creatinine, or the corresponding
estimated GFR, and calcium
 Lipid profile, after 9- to 12-hour fast, that includes
high-density and low-density lipoprotein cholesterol, and
triglycerides.
 Alb:Cr ratio: Look for microscopic albuminuria.





 Optional tests
• Measurement of urinary albumin excretion or
albumin/creatinine ratio
 Specialized investigations: for secondary hypertension not
generally indicated unless BP control is not achieved or clinically
indicated.
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Treatment Outline
Goals of Therapy
Lifestyle modification
Classification and management of BP for
adults
Pharmacologic treatment
Compelling indications for individual drug
classes
Follow-up and monitoring
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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.
• Maintain QOL and Minimize side effects.
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Lifestyle Modification
Works best in motivated individuals
Initiate at prehypertension classification
Obesity  risk for HTN and DM
Sodium “restriction” and other diet aids:
– Usual salt intake 10 gm/d = 4 gm Na+
– Reduce to 2.4 gm Na+/day
– Caution – salt substitutes contain K+
Discourage excessive consumption of coffee and other caffeine-rich
products.
Stop smoking and Alcohol consumption.
Exercise/Activity:
– 30-40 minutes 3-4x/wk, optimal 5x/wk
– Stress reduction
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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
Stopping alcohol
consumption
2–4 mmHg
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Pharmacologic Treatment
Antihypertensive Drug Classes
– Diuretics
– Angiotensin Converting Enzyme Inhibitors
(ACEI)
– Angiotensin II Receptor Blockers (ARB)
– Beta blockers
– Calcium Channel Blockers (CCB)
– Direct Vasodilators
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JNC-7 Management of BP for Adults
BP classification
Lifestyle 
Normal
Encourage
No compelling
indication
Compelling indication
< 120/80
Prehypertension
Yes
No drug tx
Drugs targeted for the
compelling indications
Yes
Thiazide for most
Drugs targeted for the
compelling indications
120-139 / 80-89
Stage I HTN
140-159 / 90-99
Stage II HTN
> 160 / > 100
Yes
2 drugs combination Drugs targeted for the
including thiazide compelling indications
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National Institute for Health and Clinical
Excellence (NICE)
NICE is an independent UK
based organisation
responsible for providing
national guidance on the
promotion of good health and
the prevention and treatment
of ill health.
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Pharmacological interventions:
In hypertensive patients aged 55 or older or black
patients of any age, the first choice for initial therapy
should either be a calcium-channel blocker or a thiazidetype diuretic. For this recommendation, black patients
are considered to be those of African or Caribbean
descent, not mixed-race, Asian or Chinese.
In hypertensive patients younger than 55, the first choice
for initial therapy should be an angiotensin-converting
enzyme (ACE) inhibitor (or an angiotensin-II receptor
antagonist if an ACE inhibitor is not tolerated).
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Pharmacological interventions:
If initial therapy was with a calcium-channel blocker or a
thiazide-type diuretic and a second drug is required, add an
ACE inhibitor (or an angiotensin-II receptor antagonist if an
ACE inhibitor is not tolerated). If therapy was initiated with
an ACE inhibitor (or angiotensin-II receptor antagonist), add
a calcium-channel blocker or a thiazide-type diuretic.
If treatment with three drugs is required, the combination of
ACE inhibitor (or angiotensin-II receptor antagonist),
calcium-channel blocker and thiazide-type diuretic should
be used.
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Pharmacological interventions:
If blood pressure remains uncontrolled on adequate
doses of three drugs, consider adding a fourth
and/or seeking expert advice.
If a fourth drug is required, one of the following
should be considered:
– a higher dose of a thiazide-type diuretic or the
addition of another diuretic (careful monitoring is
recommended) or
– beta-blockers or
– selective alpha-blockers.
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Pharmacological interventions:
If blood pressure remains uncontrolled on adequate doses of four
drugs, and expert advice has not yet been obtained, this should
now be sought.
“Beta-blockers are not a preferred initial therapy for hypertension.”
However, beta-blockers may be considered in younger people,
particularly:
– those with an intolerance or contraindication to ACE inhibitors
and angiotensin-II receptor antagonists or
– women of child-bearing potential or
– people with evidence of increased sympathetic drive.
In these circumstances, if therapy is initiated with a beta-blocker and a
second drug is required, add a calcium-channel blocker rather than a
thiazide-type diuretic to reduce the patient’s risk of developing diabetes.
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Pharmacological interventions:
When a beta-blocker is withdrawn, the dose should be
stepped down gradually. Beta-blockers should not be
withdrawn in patients who have compelling indications
for beta-blockade, for example those who have
symptomatic angina or who have had a myocardial
infarction.
Offer patients with isolated systolic hypertension (systolic
BP 160 mmHg or more) the same treatment as patients
with both raised systolic and diastolic blood pressure.
Offer patients over 80 years of age the same treatment
as other patients over 55, taking account of any
comorbidity and their existing burden of drug use.
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The Atenolol Debate
Meta-analysis of 8 randomized, controlled,
clinical studies involving atenolol
Atenolol vs. placebo (6825)
– No outcome difference for all-cause mortality, CV
mortality, or MI
– Trend for lower risk of stroke (outlier HEP?)
Atenolol vs. other antihypertensive (17,671)
– No major differences with respect to BP control
–  mortality,  trend CV mortality,  risk of stroke
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The Atenolol Debate
Authors suggestion for findings
– Perhaps all B-blockers are not created equal?
Atenolol – hydrophilic, lacks penetration into CNS
Atenolol – no benefit in remodeling, endothelial
dysfunction
More doom for Atenolol?
– ASCOT Trial was halted early
> 19,000 patients
Atenolol + Thiazide vs. Amlodipine + Perindopril
Results due in March – implication thus far for greater CV
mortality and stroke
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Pharmacological interventions:
Where possible, recommend treatment with drugs
taken only once a day.
Prescribe non-proprietary drugs where these are
appropriate and minimise cost.
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Special Considerations
 Compelling Indications
• Compelling Populations
•Blacks
• Diabetics
• Elderly
• Renovascular disease
• Pregnancy
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Compelling Indications
Compelling Indication
Initial Therapy Options
Clinical Trial Basis
Heart failure
Thiazide, BB, ACEI,
ARB, ALDO-Ant
ACC/AHA HF Guidelines, MeritHF, Copernicus, CIBIS, SOLVD,
AIRE, TRACE, ValHeft, Rales
MI
BB, ACEI, ALDO-Ant
ACC/AHA Guidelines, BHAT,
SAVE, Capricorn, Ephesus
High CAD risk
Thiazide, BB, ACEI, CCB
ALLHAT, HOPE, LIFE, Convince
Diabetes
BB, ACE, ARB, CCB
NKF-ADA Guideline, UKPDS,
ALLHAT
CRF
ACE, ARB
NKF Guideline, Captopril
trial, RENAAL, IDNT, REIN,
AASK
Recurrent Stroke
Prevention
Thaizide, ACEI
PROGRESS
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Compelling Populations
High-Risk Hypertensives:
– Blacks
– Diabetics
– Elderly
– Renovascular disease
– Pregnancy
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Blacks
The single most at risk population with HTN
– Disproportionately higher rate and more severe
Lower plasma renin activity, more Na+ and
volume-dependent hypertension
Initial tx – DIURETICS
– Second line CCB > ACEI =ARB, B-blockers
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Diabetics
Direct correlation between systolic BP and
decline in GFR
As little as a 2 mmHg  BP results in significant
reductions in CVD (HOT study)
Preferred agents – ACEI or ARBs
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Elderly
Population with the lowest BP control, yet the most to
gain!
”Isolated systolic hypertension is common”
Issues – polypharmacy, altered drug metabolism,
physiological changes
> 50% of these patients will require combination therapy
to achieve goal BP
Susceptible to volume depletion – orthostatic hypotension
Cognitive impairment
Fixed incomes
Low-dose thiazide is drug of choice
– Additional agent should include – CCB or B-blocker
“Start low and go slow”
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Renal vascular Disease
ACEI and ARBs
In patients with RAS or RA hyperplasia
– ACEI and ARBs – particularly advantageous
–  plasma renin and angiotensin activity
Caution – Rapid and profound drop in BP as
well as renal failure
Avoid in bilateral RAS
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Pregnancy
Almost all cardiovascular drugs are either risk
category C or D.
Chronic/transient hypertension vs.
preeclampsia
Treatment warranted with DBP > 100mmHg
Problem – not much data from controlled
clinical studies
Methyldopa, Hydralazine, Diuretics
Caution?
– BB, CCB
Avoid
– ACEI, ARB
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Causes of Resistant HTN
Improper BP measurement
Excess sodium intake
Inadequate diuretic therapy
Medication
–
–
–
–
Inadequate doses
Compliance
Drug interactions
OTC/herbals/dietary supplements
Excess alcohol intake
Identifiable causes of HTN
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Public Health Challenges
and Community Programs
 Public health approaches (e.g. reducing calories, saturated
fat, and salt in processed foods and increasing
community/school opportunities for physical activity) can
achieve a downward shift in the distribution of a
population’s BP, thus potentially reducing morbidity,
mortality, and the lifetime risk of an individual’s becoming
hypertensive.
 These public health approaches can provide an attractive
opportunity to interrupt and prevent the continuing costly
cycle of managing HTN and its complications.
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Population-Based Strategy
SBP Distributions
After
Intervention
Before
Intervention
Reduction
in BP
Reduction in SBP
mmHg
2
3
5
% Reduction in Mortality
Stroke CHD Total
–6
–8
–14
–4
–5
–9
–3
–4
–7
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Which is the Best Strategy
Polypill vs. Polymeal
CVD Reduction by 80%.
Wald et al. BMJ 2003
CVD Reduction by 75%.
Franco et al. BMJ 2004
Enalapril 10 mg
Thiazide 25 mg
Atenolol 25 mg
Aspirin 75 mg
Atorvastatin 10 mg
Folic acid 5 mg
Fish 114 g.
Walk, 4 times/week
Dark chocolate 100 g
Fruits and vegetables 400 g
Garlic 2.7 g
Almonds 68 g
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Follow-up and Monitoring
– Patients should return for follow-up and adjustment
of medications until the BP goal is reached.
– More frequent visits for stage 2 HTN or with
complicating comorbid conditions.
– Serum potassium and creatinine monitored 1–2 times
per year.
– After BP at goal and stable, follow-up visits at 3- to
6-month.
– Comorbidities, such as heart failure, associated
diseases, such as diabetes, and the need for
laboratory tests influence the frequency of visits.
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Continuing treatment
The aim of medication is to reduce blood pressure to
140/90 mmHg or below. However, patients not achieving
this target, or for whom further treatment is inappropriate or
declined, will still receive worthwhile benefit from the
drug(s) if these lower blood pressure.
Patients may become motivated to make lifestyle changes
and want to reduce or stop using antihypertensive drugs. If
at low cardiovascular risk and with well controlled blood
pressure, these patients should be offered a trial reduction
or withdrawal of therapy with appropriate lifestyle guidance
and ongoing review.
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Questions?