Patients Care

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

  • 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.
  • 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.
  • Hypertension results from the interplay of several pathophysiological mechanisms regulating plasma volume, peripheral vascular resistance and cardiac output, all of which may be increased.
  • 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 considered as a part of the pathogenesis of idiopathic hypertension.
  • Arsenic exposure has also many of the same signs of primary hypertension such as headache, confusion, proteinuria, visual disturbances, nausea and vomiting.
  • Due to the role of intracellular potassium in regulation of cellular pressures related to sodium, establishing potassium balance has been shown to reverse hypertension.

Signs and symptoms

  • Mild to moderate essential hypertension is usually asymptomatic.
  • Accelerated hypertension is associated with headache, somnolence, confusion, visual disturbances and nausea and vomiting.
  • Retina is affected with narrowing of arterial diameter to less than 50% of venous diameter,
  • Some signs and 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 signs and 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.
  • Signs and 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.
  • Signs and 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.

Diagnosis

  • Initial assessment of the hypertensive patient should include a complete history and physical examination to confirm a diagnosis of hypertension. Most patients with hypertension have no specific symptoms referable to their blood pressure elevation. Although popularly considered a symptom of elevated arterial pressure, headache generally occurs only in patients with severe hypertension. Characteristically, a "hypertensive headache" occurs in the morning and is localized to the occipital region. Other non specific symptoms that may be related to elevated blood pressure include dizziness, palpitations, easy fatigability and impotence.
  • Diagnosis of hypertension is generally on the basis of a persistently high blood pressure. Usually this requires three separate measurements at least one week apart. Exceptionally, if the elevation is extreme, or end-organ damage is present then the diagnosis may be applied and treatment commenced immediately.
  • When taking manual measurements, the person taking the measurement should be careful to inflate the cuff suitably above anticipated systolic pressure.
  • Tests are undertaken to identify possible causes of secondary hypertension and seek evidence for end-organ damage to the heart itself or the eyes (retina) and kidneys. Diabetes and raised cholesterol levels being additional risk factors for the development of cardiovascular disease are also tested for as they will also require management. Tests are performed e.g. urinalysis, Creatitine, electrolytes, TSH, Lipid Profile etc.

Management

  • Lifestyle changes such as the DASH (Dietary Approaches to Stop Hypertension) diet, physical exercise and weight loss have been shown to significantly reduced blood pressure in people with high blood pressure. If hypertension is high enough to justify immediate use of medications, lifestyle changes are initiated concomitantly.
  • A series of UK guidelines advocate treatment initiation thresholds and desirable targets to be reached. Of particular note is that for patients with blood pressures between 140-159/80-99 and without additional factors, that only lifestyle action and regular blood pressure and risk-factor review is proposed.
  • There are many classes of medications for treating hypertension, together called antihypertensive, which act by lowering blood pressure. Evidence suggests that reduction of the blood pressure by 5–6 mmHg can decrease the risk of stroke by 40%, of coronary heart disease by 15–20% and reduces the likelihood of dementia, heart failure and mortality from vascular disease.
  • The aim of treatment should be blood pressure control to <140/90 mmHg for most patients and lower in certain contexts such as diabetes or kidney disease (some medical professionals recommend keeping levels below 120/80 mmHg). Each added drug may reduce the systolic blood pressure by 5–10 mmHg, so often multiple drugs are often necessary to achieve blood pressure control.
  • For mild blood pressure elevation, consensus guidelines call for medically-supervised lifestyle changes and observation before recommending initiation of drug therapy. However, according to the American Hypertension Association, evidence of sustained damage to the body may be present even prior to observed elevation of blood pressure. Therefore the use of hypertensive medications may be started in individuals with apparent normal blood pressures but who show evidence of hypertension related nephropathy, proteinuria, atherosclerotic vascular disease, as well as other evidence of hypertension related organ damage.
  • If lifestyle changes are ineffective, then drug therapy is initiated, often requiring more than one agent to effectively lower hypertension. Which type of many medications should be used initially for hypertension has been the subject of several large studies and various national guidelines.