Hypertension (High Blood Pressure) : Sign & Symptoms, Causes, Risk factors, Diagnosis, Complication, Treatment and Prevention

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Hypertension is the silent killer of mankind. Most of the Sufferers are asymptomatic and hence early diagnosis is a problem. The definition of Hypertension is not universal because normal Blood Pressure varies. The dividing line between normal and abnormal Blood Pressure is arbitrary because Blood Pressure is dependent upon many factors like age, sex, race etc. The Sixth Joint National Committee Criteria classifies hypertension for adults aged 18 years and older aged personals. Normal Blood Pressure of adults aged 18 years are 120 ± 20 mm of Hg (Systolic Blood Pressure) and 80 ± 20 mm of Hg (Diastolic Blood Pressure).

Blood Pressure (BP) is the pressure of the blood within the arteries. It is produced primarily by the contraction of the heart muscle. It's measurement recorded by two numbers. The first (Systolic pressure) is measured after the heart contracts and is highest. The second (Diastolic pressure) is measured before the heart contracts and lowest. Elevation of blood pressure is called "Hypertension" or “High Blood Pressure” and diminished blood pressure is known as “Hypotension”. Systolic Blood Pressure is controlled by the stroke volume of the heart and the stiffness of the arterial vessels. Diastolic Blood Pressure is controlled by the peripheral resistance. Blood Pressure varies from moment to moment with respiration, emotion, exercise, meals, alcohol, tobacco, bladder distension, temperature and pain. It may be modified by obesity or arrhythmia. Blood Pressure is also influenced by circadian rhythm, age and race.

High blood pressure generally develops over many years, and it affects nearly everyone eventually.  It may damage the blood vessels as well as heart continues without any symptoms. Hypertensive emergencies (malignant hypertension) are characterized by severe elevations in Blood Pressure (>180/120 mmHg) with evidence of impending or progressive target organ dysfunction. They require immediate Blood Pressure reduction. It may increases the risk of serious health problems, like Pappiledema, Retinal exudates, Retinal haemorrhages, Nephropathy, Hypertensive encephalopathy, Intracerebral haemorrhage, Acute Myocardial ischemia, Acute left ventricular failure with pulmonary oedema, Unstable angina pectoris, Dissecting aortic aneurysm, Eclampsia etc.

Hypertensive urgencies (accelerated hypertension) are associated with severe elevations of blood pressure without progressive target organ dysfunction (e.g. upper levels of stage-II hypertension associated with severe headache, shortness of breath, epistaxis etc.). Retinal damage may be present but without Pappiledema.

Sign & Symptoms of Hypertension

Most of the people with high blood pressure have no signs or symptoms, even if the blood pressure reaches dangerously high levels. Some of the people with high blood pressure may have headaches, shortness of breath or nosebleeds, but these signs & symptoms aren't specific and usually don't occur until high blood pressure has reached a severe or life-threatening stage.

  1. Sign of General Examination
    1. Moon face, buffalo hump and truncal obesity - Cushing's syndrome.
    2. Puffy face, rough skin, obesity - Myxedema.
    3. Tremors, tachycardia, exophthalmos, thyroid dermopathy and goiter - Hyperthyroidism.
    4. Prognathism, dubbed hand, coarse features - Acromegaly.
    5. Pigmentation - Neurofibromatosis.
    6. Radio femoral delay and collateral vessels over the chest wall - Coarctation of aorta.
    7. Weaker left radial - Preductal coarctation.
    8. Waterhammer pulse - Aortic incompetence.
  2. Sign of Cardiovascular System
    1. Cardiomegaly
    2. Third and fourth heart sound gallop.
    3. Loud second heart sound.
    4. Early diastolic murmur - due to Al.
  3. Sign of Respiratory System
    1. Basal crepitations - LVF
    2. Rhonchi · LVF, Polyarteritis nodosa.
  4. Sign of Abdomen
    1. Hepatomegaly - Cardiac failure
    2. Palp able kidney lump - Polycystic kidney, hypernephroma.
    3. Bruit over renal artery - Renal artery stenosis.
    4. Bruit over abdominal aorta - Abdominal aortic aneurysm.

The clinical features may be due to the elevated blood pressure itself, target organ involvement or due to underlying disease, as in secondary hypertension.

  1. Symptoms due to hypertension
    1. Headache: This occurs usually in the morning hours. It is throbbing and usually frontal.
    2. Dizziness: The patient feels unsteady
    3. Epistaxis: This occurs due to increased pressure causing rupture of the capillaries of the nose. The bleeding would reduce the circulating volume, and lower the Blood Pressure (Natures way of lowering the BP and prevention of haemorrhage in the vital organs).
  2. Symptoms due to Affection of Target Organs
    1. Cardiovascular System (CVS) :
      1. Dyspnea on exertion (incipient LVF)
      2. Anginal chest pain (IHD)
      3. Palpitations
    2. Kidneys: Hematuria, nocturia, polyuria
    3. Central Nervous System (CNS)
      1. Transient ischemic attacks (TIA or stroke) with focal neurological deficit.
      2. Hypertensive encephalopathy (headache, vomiting, convulsions, unconsciousness, focal neurological deficit).
      3. Dizziness, tinnitus and syncope.
    4. Retina: Blurred vision or sudden blindness.
  3. Symptoms due to Underlying Diseases
      1. Oedema and puffy face - Acute nephritis.
      2. Weight gain, hirsutism and stria - Cushing's syndrome.
      3. Weight loss, tremors, palpitations and sweating – Hyperthyroidism / pheochromocytoma.
      4. Weakness - Primary hyperaldosteronism.
      5. Joint pains, bronchospasm &peripheral vascular disease symptoms - Polyarteritis nodosa.

Causes of Hypertension

There are two types of hypertension; Primary (essential) hypertension and Secondary hypertension. Primary hypertension has no identifiable cause of high blood pressure. Most of the adult persons have this type of high blood pressure and it’s tends to develop gradually over many years. Some people have high blood pressure caused by an underlying condition, called Secondary hypertension. Secondary hypertension tends to appear suddenly and cause higher blood pressure than does primary hypertension. Various conditions and medications can lead to secondary hypertension, including:

  • Renal :
    • Acute nephritis
    • Interstitial nephritis and pyelonephritis
    • Polycystic kidneys
    • Renal artery stenosis
    • Diabetic nephropathy
  • Endocrine: Pheochromocytoma, Cushing's syndrome, thyrotoxicosis, myxedema
  • Neurological: Raised intracranial tension, lead encephalopathy, etc.
  • Pregnancy induced Hypertension
  • Cardiovascular Hypertension : Co-arctation of aorta, aortic regurgitation, arteriosclerosis
  • Drugs: Glucocorticoids, OCPs, sibutramine, cocaine, amphetamines, cold remedies, decongestants,
  • Miscellaneous: Polycythemia, polyarteritis, nodosa, obstructive sleep apnea, hypercalcemia, Alcohol abuse or chronic alcohol use.

Risk Factors of Hypertension

Most of the hypertension is associated with elevated blood pressure itself, target organ involvement or due to underlying disease, as in Secondary hypertension. Genetics factor can also play a role in an individual’s development of hypertension - even if the person has no familial history of hypertension.

The dividing line between normal and abnormal Blood Pressure is arbitrary because Blood Pressure is dependent upon many factors like age, sex, race etc. Some of the most common risk factors for developing hypertension are as follows:

  • Age & Gender: Advancing age is a primary risk factor for the disease and incidence rates are not equal for all ages. Through early middle age, or about age 45, high blood pressure is more common in men. Women are more likely to develop high blood pressure after age 65.
  • Race: High blood pressure is particularly common among blacks, often developing at an earlier age than it does in whites. Serious complications, such as stroke, heart attack and kidney failure, also are more common in blacks.
  • Family history: High blood pressure tends to run in families. Family members share genes, behaviors, lifestyles and environments that can influence their health and their risk for disease.
  • Overweight or Obese: Diet having high in calories, fats and sugars, and low in essential nutrients contributes directly to poor health as well as obesity, which affects blood pressure. In addition, eating too much salt and not enough potassium can raise blood pressure to dangerous levels.
  • Physically activity: Physical activity is good for your heart and circulatory system. When person lead an active lifestyle then they are less likely to gain an unhealthy amount of weight. Being overweight or obese is a common precursor to high blood pressure.
  • Unhealthy life style :
    • Using tobacco: Smoking or chewing tobacco immediately raises blood pressure temporarily, and also the chemicals in tobacco can damage the lining of your artery walls. This can cause arteries to narrow, increasing blood pressure.
    • Sodium consumption: Too much sodium in diet can cause body to retain fluid, which increases blood pressure.
    • Potassium consumption:  Potassium helps to balance the amount of sodium in the cells. If the person don't get enough potassium in the diet or retain enough potassium, he/she may accumulate too much sodium in the blood circulation. Low potassium consume in the diet provoke hypertension.
    • Vitamin D: It's uncertain if having too little vitamin D in diet can lead to high blood pressure. Vitamin D may affect an enzyme produced by kidneys that affects blood pressure.
    • Drinking alcohol: Heavy drinking of alcohol can damage heart &liver.
  • Stress: High levels of stress can lead to a temporary increase in blood pressure.
  • Medical conditions: Certain chronic conditions also may increase risk of high blood pressure, such as kidney disease, Diabetes mellitus and sleep apnea.
  • Pregnancy: Sometimes pregnancy contributes to high blood pressure.

Although high blood pressure is most common in adults, children may be at risk, too. For some children, high blood pressure is caused by problems with the kidneys or heart. But for a growing number of kids, poor lifestyle habits, such as an unhealthy diet, obesity and lack of exercise, contribute to high blood pressure.

Diagnosis of hypertension

Most of the Sufferers are asymptomatic and hence the early stages of hypertension are difficult to diagnose. Some of the following investigation can performed for the diagnosis of hypertension:

  • To assess target organ damage

    • X-ray chest for heart size
    • ECG for LV hypertrophy and evidence of IHD
    • Echocardiogram for LV systolic and diastolic functions
    • Urinalysis – Proteinuria >200 mg/day and haematuria suggest renal involvement. Further investigations include serum creatinine, renal sonography, isotopic renogram, renal biopsy.
  • To Detect the Cause of Hypertension

    • X-ray chest
      • Rib notching suggests coarctation of aorta.
      • Mediastinal widening suggests aortic dissection
    • Imaging of abdomen ( Sonography, CT scan, MRI) to detect:
      • Polycystic kidney
      • Tumour of kidney
      • Renal calculi
      • Adrenal tumour
      • Pheochromocytoma
    • Urinary catechols or breakdown products (Metanephrine or VMA) – Pheochromocytoma
    • Echocardiogram - Coarctation of aorta
    • IVP for renovascular hypertension, kidney tumours and stones
    • Aortography - for aneurysm and coarctation of aorta

Complication of Hypertension

The excessive pressure on the artery walls caused by high blood pressure can damage blood vessels, as well as organs in the body. The higher blood pressure and the longer it goes uncontrolled, the greater the damage. The common organs damaged by long-standing hypertension are heart, kidneys, blood vessels, retina and central nervous system.

  • Cardiovascular System: Increased myocardial work leads to concentric hypertrophy of left ventricle, angina pectoris and accelerated coronary artery disease. There is systolic as well as diastolic dysfunction.
  • Renal System: Progressive arteriosclerosis involves both the efferent and afferent renal arterioles and capillaries of glomerular tuft. This leads to compromise in renal function, shrinkage of kidney, proteinuria.
  • Nervous System: Hypertension may cause micro-aneurysms (Charcot-Bouchard aneurysms) which may rupture and cause cerebral haemorrhage. Accelerated atherosclerosis may cause cerebral thrombosis, embolism and infarction. Cerebral arteriolar spasm may cause hypertensive encephalopathy. Sites of hypertensive bleed are: cerebellum, thalamus, basal ganglia (putamen), pons. Trouble with memory or understanding: Uncontrolled high blood pressure may also affect the ability to thinking, remembering and learning. Trouble with memory or understanding concepts is more common in people with high blood pressure.
  • Aneurysm: Increased blood pressure can cause blood vessels to weaken and bulge, forming an aneurysm. If an aneurysm ruptures, it can be life-threatening.
  • Thickened, narrowed or torn blood vessels in the eyes can loss the vision.
  • Metabolic syndrome: Metabolic syndrome is a cluster of disorders of the body's metabolism, including increased waist circumference; high triglycerides; low high-density lipoprotein (HDL) cholesterol, the "good" cholesterol; high blood pressure; and high insulin levels. These conditions make more likely to develop diabetes mellitus, heart disease and stroke.

Treatment of Hypertension

Treatment for high blood pressure includes ongoing care, as well as individual treatments tailored for specific situations and younger age groups, including children and teens. Some of the following medications are used for the treatment of hypertension :

  1. Diuretics: Oral diuretics were the most widely used anti-hypertensive agents. They are effective alone in 50% of mild hypertensives. Thiazides are very effective. They are well tolerated and need to be given only once a day. They enhance the potency of other anti-hypertensives. They act by reducing extracellular fluid volume and cardiac output and they help to counteract the hypertensive effect of high salt intake. They can aggravate diabetes by suppressing release of insulin due to hypokalemia. Hyperlipidemia, hyperuricemia, hypokalemia, hyponatremia, hypomagnesemia may occur. Now they are usually used in combination therapy.
  2. Beta blockers: Reduce cardiac output and lower BP but raise the peripheral resistance on acute administration { which increases BP). However, on chronic administration, BP falls to pre-treatment levels. In mild to moderate hypertension, it lowers the BP to less than 90 mmHg in more than 50% patients. Drug withdrawal, if needed, should be done slowly, or rebound hypertension may occur. They can be combined with diuretics, calcium blockers, ACE inhibitors and vasodilators. They may precipitate bronchospasm, cardiac failure, peripheral vascular disease, impotence and depression.
  3. Calcium Channel Blockers: Lower BP by:
    1. Natriuresis and diuresis due to increased GFR and decreased aldosterone
    2. Anti-angiotensin-11 effect
    3. Direct negative inotropic effect which lowers cardiac output
    4. Peripheral vasodilatation

Nifedipine was the commonest used calcium blocker. Now Amlodipine is replacing it. Felodipine, nicardipine, nitrendipine and cilnidipine are other useful calcium blockers. These drugs are especially useful in elderly hypertensives. Flushing, headache, palpitations, oedema and hypotension may occur.

  1. ACE Inhibitors: Renin released from the kidney acts on circulating angiotensinogen to produce angiotensin-I, which is converted to angiotensin-II by converting enzyme. Angiotensin-II is a potent vasoconstrictor and it stimulates aldosterone, which retains sodium and causes hyper-tension. ACE inhibitors act by inhibiting the converting enzyme preventing the formation of angiotensin-II and lowering of BP. They also act by reducing the degradation of bradykinin; a potent vasodilator, which lowers the Blood Pressure.

ACE Inhibitors cause regression of ventricular hypertrophy, attenuation of reperfusion injury induced ventricular arrhythmias, preload and afterload reduction and coronary vasodilatation. These drugs have no adverse effects of lipids, uric acid or glucose metabolism. They lower the BP by 15-25%. Diastolic pressure is lowered more than systolic pressure. Concomitant sodium restriction and diuretics further lowers BP by 15-25%.

ACE Inhibitors are useful in renovascular hypertension. High angiotensin II is however required to maintain adequate filtration pressure behind the stenotic lesion. ACE Inhibitors decrease the perfusion pressure and lead to azotaemia. Thus, they are contraindicated in bilateral renal artery stenosis. These drugs are useful in hypertensive diabetics because of neutral effect of carbohydrate metabolism. In addition they decrease microalbuminuria. Captopril also improves insulin sensitivity. It has a short duration of action and is used for cardiac failure. Enalapril, lisinopril, perindopril, ramipril, etc. are longer acting ACE inhibitors and useful in hypertension. Tissue specific ACE inhibitors like Quinapril, Ramipril, Perindopril, Fosinopril are available.

  1. Angiotensin II Blockers are useful in patients with ACE Inhibitor-induced cough and in elderly hypertensives. Losartan, Irbesartan, Valsartan, Candersartan are available.
  2. Alpha Blockers: Adrenergic stimulation of alpha- I receptors in the vascular smooth muscles causes vasoconstriction and hypertension. Alpha blockers attenuate vasoconstriction, and thereby decrease vascular resistance and blood pressure. Prazosin was the first alpha blocker with short duration of action. Terazosin and doxazosin are longer acting, once a day alpha blockers. The efficacy can be enhanced by the concomitant use of diuretics. The most dramatic adverse effect is the first dose postural hypotension/ syncope. Alpha blockers also have other beneficial effects like lowering of lipids, regression of left ventricular hypertrophy, enhancing insulin sensitivity (hence ideal for diabetic hypertensives) and relief of obstructive symptoms in benign prostatic hypertrophy.
  3. Vasodilators: These drugs act on the arteriolar smooth muscles, causing vasodilatation and lowering of BP. However, reflex tachycardia and increase in cardiac output limits its usefulness in severe coronary artery disease. These effects can be reduced by combining hydralazine with beta blockers. Minoxidil is the other vasodilator whose usefulness is limited due to hirsutism in females. Diazoxide and nitroprusside are parenteral vasodilators useful in hypertensive

Prevention of Hypertension

 Lifestyle changes can help to control and prevent high blood pressure. These have been practice over the years, even when no drugs were available and their value established. They help to control hypertension in some, but are useful as adjutants to drug treatment in almost all patients. They include the following:

  1. Salt restriction: Modest sodium restriction upto 110 mmol/day (2.4 gm sodium or 6 gm sodium chloride) is effective in controlling hypertension in mild to moderate hypertension because sodium and water retention is involved in large proportion of hypertensives.
  2. Weight reduction: In overweight persons, reduction of l kg may reduce 1.6/ l.3 mmHg Blood Pressure. It also modifies other CVS risk factors like Diabetes mellitus and dyslipidaemia. Blood pressure is lowered by:
    1. Reduced circulating volume which reduces venous return and cardiac output.
    2. Reduced sympathetic activity and plasma nor-epinephrine.
    3. Reduction in hyperinsulinemia
  3. Stop smoking: Smoking acutely raises BP. In addition, it is an independent and most important reversible coronary risk factor. Since tolerance develops to nicotine-induced hemodynamic effects, chronic smoking may not be associated with high BP.
  4. Diet:
    1. Lacto-vegetarian diet and high intake of poly unsaturated fish oils have high potassium levels and lower BP by:
      1. Increased sodium excretion.
      2. Decreased sympathetic activity.
      3. Decreased renin-angiotensin secretion and direct dilatation of renal arteries.
    2. Adequate calcium, magnesium intake should be maintained in the diet.
    3. Saturated fat and cholesterol intake should be reduced for overall cardiovascular health.
  1. Limit of alcohol intake upto <1 ounce/day of ethanol [24 ounces beer, 8 ounces wine or 2 ounces 100-proof whiskey].
  2. Relaxation: Various forms of relaxation like yoga, biofeedback and psychotherapy lower BP, especially in those with sympathetic.
  3. Regular exercise

 

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One thought on “Hypertension (High Blood Pressure) : Sign & Symptoms, Causes, Risk factors, Diagnosis, Complication, Treatment and Prevention

  1. It’s an amazing information in detail about the Hypertension.
    How can it be under control in our busy schedule of daily life?

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