is a chronic medical condition in which the blood pressure is elevated.
It is also referred to as high blood pressure. The word "hypertension",
by itself, normally refers to systemic, arterial hypertension.
can be classified as either essential (primary) or secondary. Essential
or primary hypertension means that no medical cause can be found
to explain the raised blood pressure. It is common. About 90-95%
of hypertension is essential hypertension. Secondary hypertension
indicates that the high blood pressure is a result of another condition,
such as kidney disease or tumors.
is one of the most common complex disorders. The etiology of hypertension
differs widely amongst individuals within a large population. Essential
hypertension is the form of hypertension that by definition has
no identifiable cause.
It is the more common type and affects 90-95% of hypertensive
patients and even though there are no direct causes, there are
many risk factors such as sedentary lifestyle, obesity etc.
Salt sensitivity, alcohol intake and vitamin D deficiency.
It is also related to aging and to some inherited genetic mutations.
Family history increases the risk of developing hypertension.
Renin elevation is another risk factor.
Insulin resistance which is a component of syndrome X, or the
metabolic syndrome is also thought to cause hypertension.
Recently low birth weight has been questioned as a risk factor
for adult essential hypertension.
hypertension by definition results from an identifiable cause.
This type is important to recognize since it's treated differently
than essential type by treating the underlying cause.
Many secondary causes can cause hypertension; some are common
and well recognized secondary causes such as Cushing's syndrome,
which is a condition where both adrenal glands can overproduce.
The hormone cortisol. Hypertension results from the interplay
of several pathophysiological mechanisms regulating plasma volume,
peripheral vascular resistance and cardiac output, all of which
may be increased.
More than 80% of patients with Cushing's syndrome have hypertension.
Another important cause is the congenital abnormality coarctation
of the aorta. The symptoms are obesity sweating and anxiety.
A variety of adrenal cortical abnormalities can cause hypertension,
in primary aldosteronism there is a clear relationship between
the aldosterone-induced sodium retention and the hypertension.
Other well known causes include diseases of the kidney. This
includes diseases such as polycystic kidney disease which is
a cystic genetic disorder of the kidneys.
Neuroendocrine tumors are also a well known cause of secondary
medications, especially NSAIDs (Motrin/Ibuprofen) and steroids
can cause hypertension. High blood pressure that is associated
with the sudden withdrawal of various antihypertensive medications
is called rebound hypertension.
Few women of childbearing age have high blood pressure; up to
11% develop hypertension of pregnancy.
Another common and under-recognized sign of hypertension is
Because of the presence of arsenic in ground water supplies
and its effect on cardiovascular health, low dose arsenic poisoning
should be inferred as a part of the pathogenesis of idiopathic
hypertension. Idiopathic and essential are both somewhat synonymous
with primary hypertension.
Arsenic exposure has also many of the same signs of primary
hypertension such as headache, somnolence, confusion, proteinuria
visual disturbances and nausea and vomiting.
Due to the role of intracellular potassium in regulation of
cellular pressures related to sodium, establishing potassium
balance has been show to reverse hypertension.
to moderate essential hypertension is usually asymptomatic.
Accelerated hypertension is associated with headache, somnolence,
confusion, visual disturbances and nausea and vomiting.
Retinas are affected with narrowing of arterial diameter to
less than 50% of venous diameter.
Some symptoms are especially important in infants and neonates
such as failure to thrive, seizure, irritability or lethargy
and respiratory distress.
In children hypertension may cause headache, fatigue, blurred
vision, epistaxis and bell palsy.
symptoms are especially important in suggesting a secondary
medical cause of chronic hypertension, such as centripetal obesity.
In hyperthyroidism there may be weight loss, tremor, tachycardia
, palmer erythema and sweating.
symptoms associated with growth hormone excess such as coarsening
of facial features, prognathism, macroglossia, hypertrichosis,
hyperpigmentation and hyperhidrosis may occur in these patients.
The typical attack lasts from minutes to hours and is associated
with headache, anxiety, palpitation, profuse perspiration, pallor,
tremor and nausea and vomiting. Blood pressure is markedly elevated.
associated with pre-eclampsia and eclampsia, can be proteinuria,
edema and hallmark of eclampsia which is convulsions, Other
cerebral signs may precede the convulsion such as nausea, vomiting,
headaches and blindness.
High blood pressure that is associated with the sudden withdrawal
of various antihypertensive medications is called rebound hypertension.
Prevention and risk
degree to which hypertension can be prevented depends on a number
of features including: current blood pressure level, sodium/potassium
balance, detection and omission of environmental toxins, changes
in end/target organs (retina, kidney, heart among others), risk
factors for cardiovascular diseases and the age at presentation.
Unless the presenting patient has very severe hypertension,
there should be a relatively prolonged assessment period within
which repeated measurements of blood pressure should be taken.
Following this, lifestyle advice and non-pharmacological options
should be offered to the patient, before any initiation of drug
The process of managing hypertension according the guidelines
of the British Hypertension Society suggest that non-pharmacological
options should be explored in all patients who are hypertensive
Weight reduction and regular aerobic exercise (e.g., walking)
are recommended as the first steps in treating mild to moderate
hypertension. Regular exercise improves blood flow and helps
to reduce resting heart rate and blood pressure.
Several studies indicate that low intensity exercise may be
more effective in lowering blood pressure than higher intensity
exercise. These steps are highly effective in reducing blood
pressure, although drug therapy is still necessary for many
patients with moderate or severe hypertension to bring their
blood pressure down to a safe level.
Reducing dietary sugar intake.
Reducing sodium (salt) in the diet may be effective: It decreases
blood pressure in about 33% of people . Many people use a salt
substitute to reduce their salt intake.
Additional dietary changes beneficial to reducing blood pressure
include the DASH diet (dietary approaches to stop hypertension)
which is rich in fruits and vegetables and low-fat or fat-free
dairy foods. This diet has been shown to be effective based
on research sponsored by the National Heart, Lung and Blood
In addition, an increase in dietary potassium, which offsets
the effect of sodium has been shown to be highly effective in
reducing blood pressure.
Discontinuing tobacco use and alcohol consumption has been shown
to lower blood pressure. The exact mechanisms are not fully
understood, but blood pressure (especially systolic) always
transiently increases following alcohol or nicotine consumption.
Since smoking substantially increases the
intensity of existing systemic diseases as well as being a major
factor in development of hypertension, it is important that
this habit should be avoided.
Excessive consumption of coffee (caffeine
ingestion) also increases blood pressure transiently but does
not produce chronic hypertension.
Reducing stress, for example with relaxation
therapy, such as meditation and other mind body relaxation techniques,
by reducing environmental stress such as high sound levels and
over-illumination can be an additional method of reducing hypertension.