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INTRODUCTION
An elevated arterial
pressure is probably the most important public
health problem in developed countries. It is
common, asymptomatic, readily detectable,
usually easily treatable, and often leads to
lethal complications if left untreated.
The prevalence of hypertension depends on both
the racial composition of the population studied
and the criteria used to define the condition.
In a white suburban population like that in the
Framingham Study, nearly one-fifth of
individuals have blood pressures >160/95, while
almost one-half have pressures >140/90. An even
higher prevalence has been documented in the
nonwhite population. In females the prevalence
is closely related to age, with a substantial
increase occurring after age 50. This increase
is presumably related to the hormonal changes of
menopause, although the mechanism is unclear.
Thus, the ratio of hypertension frequency in
women versus men increases from 0.6 to 0.7 at
age 30 to 1.1 to 1.2 at age 65.
The prevalence of various forms of secondary
hypertension depends on the nature of the
population studied and on how extensive the
evaluation is.
Patients with arterial hypertension and no
definable cause are said to have primary,
essential, or idiopathic hypertension.
Undoubtedly, the primary difficulty in
uncovering the mechanism(s) responsible for the
hypertension in these patients is attributable
to the variety of systems that are involved in
the regulation of arterial pressure peripheral
and/or central adrenergic, renal, hormonal, and
vascular and to the complexity of the
interrelations of these systems.
Patients who are classified as having labile
hypertension are those who sometimes, but not
always, have arterial pressures in the
hypertensive range. These patients are often
considered to have borderline hypertension.
Though a patient with malignant hypertension
often has a blood pressure above 200/140, the
condition is defined by the presence of
papilledema, usually accompanied by retinal
hemorrhages and exudates, rather than by the
absolute pressure level. Accelerated
hypertension is defined as a significant recent
increase over previous hypertensive levels
associated with evidence of vascular damage on
funduscopic examination but without papilledema.
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OBJECTIVE
To promote primary
prevention of hypertension and cardiovascular disease by
changes in the diet and lifestyle of the whole
population. To increase the detection and treatment of
undiagnosed hypertension. To ensure that patient on anti
hypertensive drugs are controlled to optimal BP levels.
To reduce the risk of cardiovascular disease of
hypertensive patients non-pharmacological measures and
by appropriate use of statins and aspirin.
To increase the
identification and treatment of patients with mild
hypertension who are at risk of cardiovascular disease;
elderly with IHD, diabetics, people with TOD, and those
with multiple risk factors.
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MEASUREMENT OF BLOOD PRESSURE
All adults should have b p measured routinely at least
every five years and those with high normal (SBP 130-139
DBP85-89) or people who had high bp readings at any time
previously should have their bp measured annually.
Seated BP is usually sufficient but standing bp is
measured**** in elderly and diabetics to exclude
ortostatic hypotension Average two readings at each of
visit should be used to guide the decision to treat.
Ambulatory bp should be used in special subsets of
patients. *****.
Measurement of blood
pressure should be done by standard mercury
sphygmomanometer or semiautomated device Use
a properly maintained, calibrated and validated device
Measure sitting blood pressure routinely: standing blood
pressure should be recorded at least at initial
recording in elderly and diabetics.
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Remove tight clothing
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support heart at arm
level
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ensure arm relaxed
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avoid talking during the
measurement procedure.
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Use cuff of appropriate
size
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Lower mercury column
slowly and Read blood pressure to nearest of 2mmHg
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measure diastolic blood
pressure as disappearance of sounds.
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Take at least two
readings.
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Do not treat on the
basis of isolated readings
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EVALUATION OF HYPERTENSIVE PATIENT
All hypertensive patients
should have a thorough history and physical examination
and limited no of routine investigation i.e. urine for
R/M, serum creat , fasting blood sugar, lipid profile
and ecg. The purpose of evaluation is to assess cause of
htn , cardiovascular risk assessment, evidence of target
organ damage & co morbid diseases, which may influence
treatment decision. Evaluation of patient should be done
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CAUSES OF HTN
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Drugs
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Renal disease
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Renovascular disease
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Phaechromocytoma
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Cons syndrome
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Coarctation
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Cushings
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Contributory factors
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Overweight
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Excess alcohol
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Excess salt intake
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Lack of exercise
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Environmental factors
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Complications of htn and TOD
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Stroke,TIA
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LvhHeart failure
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CAD,MI, angina, CABG
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Peripheral vascular disease
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Renal imrairment
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Risk factors for cardiovascular
disease
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Smoking
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Diabetes
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Total& Hdl cholesterol ratio
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Family history
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Age
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Sex
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Classification of Blood Pressure Level
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Category |
Systolic BP mm of Hg |
Diastolic BP mm of Hg |
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Blood Pressure |
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Optimal |
<120 |
<80 |
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Normal |
<130 |
<85 |
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High Normal |
130-139 |
80-89 |
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Hypertension |
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Grade 1 Mild |
140-149 |
90-99 |
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Grade 2 Moderate |
160-169 |
100-109 |
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Grade 3 Severe |
¡Ã180 |
¡Ã110 |
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Isolated Systolic Htn |
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Grade 1 |
140-159 |
<90 |
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Grade 2 |
¡Ã160 |
<90 |
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Drug treatment is
recommended in patients with sustained grade2 htn
(¡Ã160/100 mm of hg). All patients with grade I htn
(sbp140-159 or dbp 90-99, or both) should be offered
treatment with antihypertensive drugs if there is any
complication of htn or evidence of TOD, or diabetes, or
if there is an estimated 10 year risk of cardiovascular
disease of ¡Ã20% despite lifestyle advice.
When decided not to treat
mild htn with drugs lifestyle measures should be
encouraged and bp and risk of cardiovascular disease
should be assessed annually. The reason for this is bp
will rise within next five years requiring treatment in
10-15% of patients and risk of cardiovascular disease
will rise with age.
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White-Coat Hypertension
White-coat
hypertension is defined as a clinic blood
pressure of 140/90 mm Hg or higher on at least
three occasions, with at least two sets of
measurements of less than 140/90 mm Hg in non
clinic settings, plus the absence of
target-organ damage. The diagnosis is important
because it is generally accepted that patients
with white-coat hypertension are at relatively
low risk and are unlikely to benefit from
antihypertensive-drug treatment. Several studies
have shown that drug treatment of white-coat
hypertension reduces the clinic blood pressure
but has a negligible effect on the ambulatory
blood pressure, which by definition is normal.
In addition, the only study to investigate the
effects of treating white-coat hypertension on
morbid events found no significant benefit.
Sustained hypertension may develop in some
patients with white-coat hypertension, and the
risk of stroke may increase after six years.
Therefore, long-term follow-up with repeated
ambulatory blood-pressure monitoring or home
monitoring is essential. White-coat hypertension
is the only indication for ambulatory
blood-pressure monitoring.
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Labile Hypertension
Labile hypertension is
something of a misnomer, because all hypertension is
labile. However, ambulatory blood-pressure monitoring
may prove helpful in some patients with a history of
paroxysmal hypertension. Pheochromocytoma may be
suspected in some of these patients, but the
hypertension associated with this condition is not
always labile. A much more common cause of labile
hypertension is panic attacks, which have been shown to
be accompanied by surges in both blood pressure and
heart rate. Currently, no norms exist for determining
whether blood-pressure variability over a 24-hour period
is greater than normal among patients with labile
hypertension.
Resistant Hypertension
An exaggerated white-coat
effect may be suspected in some patients whose clinic
blood pressure remains high even though they are taking
three or more antihypertensive drugs. Two prospective
studies have shown that a subgroup of patients with
resistant hypertension according to clinic
blood-pressure criteria have normal ambulatory blood
pressure and a benign prognosis. However, these patients
with apparently resistant hypertension could probably be
identified with the use of home monitoring.
Masked Hypertension
In the past few years,
interest has increased in the phenomenon of masked
hypertension, defined as a normal clinic blood pressure
and a high ambulatory blood pressure. This condition is
the reverse of white-coat hypertension. The clinic blood
pressure of patients with masked hypertension may
underestimate the risk of cardiovascular events. Studies
have shown that masked hypertension in patients with
untreated hypertension and often in those with
undiagnosed hypertension is associated with an increased
rate of target-organ damage and an adverse prognosis.
The prevalence of masked hypertension in the general
population could be as high as 10 percent. As with
white-coat hypertension, masked hypertension may be
suspected on the basis of high blood-pressure
measurements taken at home.
Postural Hypotension
Postural hypotension is not
an uncommon finding in older patients who become dizzy
when standing for long periods and who may also have
syncopal episodes. The blood pressure of patients with
postural hypotension is unusually labile and depends on
their body position. When such patients are supine, the
blood pressure may be quite high, particularly during
the night. Treatment with vasopressor drugs and
antigravity stockings is a compromise between permitting
the blood pressure to go too low and making it go too
high. Therefore, ambulatory blood-pressure monitoring is
essential for evaluating optimal blood-pressure control. |
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TREATMENT
GOAL
Hypertension optimal trial
(HOT) still provides the best evidence on optimal
targets. It reported on basis of treatment analysis that
optimal blood pressure for reduction of major
cardiovascular events was 139/83 and reduction of blood
pressure below this level caused no harm. However,
patients with blood pressure between 136/83 and 150/90
were also not disadvantaged.
Drug treatment should be
started in all patients with sustained blood
pressure>169/90 or diastolic blood pressure > 100
despite non pharmacological measures.
Drug treatment is also
indicated in patients with sustained sbp140- 159 or dbp
90-99 if TOD is present or there is evidence of
established cardiovascular disease or diabetes or if
there is a 10 year cardiovascular disease risk ¡Ã 20%
For most of the patients
target of 140/85 is recommended however those with
established diabetes, renal or cardiovascular disease a
lower target of,130/80 is recommended.
When using ambulatory blood
pressure readings mean daytime pressure are preferred
and this value is expected to approximately 10/5 mmHg
lower than the clinic bp equivalent for both threshold
and targets.
LIFESTYLE
Recent trials have
reinforced recommendations that certain lifestyle
measures can lower blood pressure. Hence advice of
lifestyle modifications should be provided to all people
with high blood pressure, borderline or high normal
blood pressure. This approach can reduce age associated
rise in blood pressure and therefore reduce large
proportion of people with high normal blood pressure who
would eventually require drug therapy.
Maintain normal weight for
adults (BMI 20-25 Kg/mg©÷)
Reduce salt intake to <100 mmol (6g NaCl or <2gNa+/day
Limit alcohol consumption to ¡Â 3 units/day for men and
¡Â 2 units/day
Engage in regular aerobic physical exercise (brisk
walking rather than weight lifting) for ¡Ã30 min /day on
most of the days of week but at least on three days of
the week.
Consume at least five portions /day of fresh fruit &
vegetables.
Reduce intake of total & saturated fat.
Lifestyle measures that
reduce cardiovascular risk include smoking cessation,
reducing fat intake, replacing saturated fats with
mono-saturated fat like olive, rapeseed oil.
CHOICE OF
AGENTS
For each class of
antihypertensive drug compelling indication exist for
use in specific
groups of patients and also compelling
contraindications.
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YOUNGER (<55yrs) |
OLODER (>55yrs) |
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STEP 1 |
A (or B) |
C or D |
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STEP 2 |
A (or B) +C or D
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STEP 3 |
A (or B) +C or D
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STEP 4 RESISTANT HTN |
Add either a¥á
blocker or spironolactone or other diuretic |
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A; ACE inhibitor or
angiotensin receptor blocker
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B; ¥â blocker
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C; Calcium channel
blocker
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D; Diuretic (thiazide &
thiazide like)
INDICATION
FOR SPECIALIST REFERRAL
URGENT
TREATMENT NEEDED
Accelerated hypertension (severe hypertension & grade
III-IV retinopathy)
Severe hypertension (>220/120mmHg)
Impending complication (eg.TIA, LVF)
POSSIBLE UNDERLYING CAUSE
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Secondary hypertension
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Elevated serum creatnine
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Proteinuria or haematuria
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Sudden onset or worsening of hypertension
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Resistance to multi drug regime ( ¡Ã3 drugs)
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Young age (<30 years)
THERAPUTIC PROBLEMS
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Multiple drug intolerance
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Multiple drug contraindications
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Persistent non-adherence or non-compliance
SPECIAL SITUATIONS
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Unusual blood pressure variability
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Possible white oat hypertension
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Hypertension in pregnancy
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FOLLOW UP
The follow up of treated
patients with adequate blood pressure control depends on
factors including severity and variability of blood
pressure, complexity of treatment regimeand compliance.
Six monthly review is sufficient when blood pressure is
stable. The routine follow up visits should be simple,
measure blood pressure, weight, inquire about general
health side effects reinforce lifestyle advice and
adherence to drug therapy, and test for proteinuria
annually.
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SUMMARY
All patients with high blood
pressure, borderline or high normal blood pressure
should be advised on lifestyle modifications.
Initiate therapy if
sustained systolic blood pressure ¡Ã160mmHg or sustained
diastolic blood pressure¡Ã100mmHg.
If sustained systolic blood
pressure ¡Ã140-159mmHg or sustained diastolic blood
pressure¡Ã90-99mmHg consider initiating treatment if
cardiovascular risk or TOD is present, or if estimated
10 years cardiovascular risk is ¡Ã20%.
Non-diabetic patients
optimal goals are <140/85 mmHg.
In diabetic patients
initiate antihypertensive treatment if SBP ¡Ã140mmHg
orDBP¡Ã90 mmHg.
Optimal goals for diabetic,
CKD, or established cardiovascular disease patients
<130/80mmHg.
Most of the hypertensive
patients require at least two drugs to achieve
recommended goals.
Low dose aspirin (75mg) is
recommended for secondary prevention of ischemic
cardiovascular disease,& for those >50 years and 10 year
risk of cardiovascular disease ¡Ã20%.
Statins are recommended for
all people with high blood pressure complicated by
cardiovascular disease irrespective of baseline lipid
profile & primary prevention for those with 10 year risk
of cardiovascular disease ¡Ã20%.
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