Prevention First

HYPERTENSION

Hypertension 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.

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.

Causes

Essential hypertension

Hypertension 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.

Secondary hypertension

  • Secondary 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 hypertension.
  • Certain 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 sleep apnea.
  • 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.

Symptoms

  • Mild 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.
  • Some 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.
  • Symptoms 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

  • The 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 therapy.
  • 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 or pre-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 Institute.
  • 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.