HYPERTENSION - What a Horrible Killer!!!

[Abbas Bubakar El-ta'alu]

          Dear members, the information hereby forwarded may seem more understadable to Medical students and Physicians. All the same, go through it, there are many of its aspects that you would understand;and that may be useful to you or someone close to you!!!

          Hypertension or high blood pressure is a medical condition in which the blood pressure is chronically elevated. The condition can be classified either essential (primary) or secondary. Essential hypertension indicates that no specific medical cause can be found to explain a patient's condition. Secondary hypertension, on the other hand, indicates that the high blood pressure is a result of (i.e., secondary to) another condition, such as kidney disease or tumours (pheochromocytoma and paraganglioma). The control of increased arterial blood pressure in those with hypertension is an important medical and social challenge. Hypertension is considered to be a major cause of heart attacks and strokes (see below). An interesting fact, however, is that out of all hypertension cases, only 10 percent of patients have an established cause explaining their condition. For example, narrowing of the aorta, adrenal tumours or glomerulonephritis produces hypertension secondarily. In 90 percent of patients, the cause of hypertension is unknown. In such cases, the patient has "essential hypertension" .
          As earlier mensioned, persistent hypertension is one of the risk factors for strokes, heart attacks, heart failure and arterial aneurysm, and is a leading cause of chronic renal failure. Even moderate elevation of arterial blood pressure leads to shortened life expectancy. Only God Knowa how long a person can live, nevertheless, at severely high pressures, defined as mean arterial pressures 50% or more above average, a person can expect to live no more than a few years unless appropriately treated.
         There are several categories of blood pressure, including:
•    Normal: Less than 120/80
•    Prehypertension: 120-139/80-89
•    Stage 1 high blood pressure: 140-159/90-99
•    Stage 2 high blood pressure: 160 and above/100 and above
People whose blood pressure is above the normal range should consult their doctor, immediately, about methods for lowering it.
   In individuals older than 50 years, hypertension is considered to be present when a person's systolic blood pressure is consistently 140 mm Hg or greater. Beginning at a systolic pressure of 115 and diastolic pressure of 75 (commonly written as 115/75 mm Hg), cardiovascular disease (CVD) risk doubles for each increment of 20/10 mmHg. Prehypertension is defined as blood pressure from 120/80 mm Hg to 139/89 mm Hg. Prehypertension is not a disease category; rather, it is a designation chosen to identify individuals at high risk of developing hypertension. Resistant hypertension is defined as the failure to reduce BP to the appropriate level after taking a three-drug regimen. Every country, in essence, has some guidelines for treating resistant hypertension.

What then causes hypertension?

         Although no specific medical cause can be determined in essential hypertension, it often has several contributing factors. These include smoking, obesity, salt sensitivity, renin homeostasis, insulin resistance, genetics, and age.
Smoking: those that smoke should immediately quit the nonsensity.
Obesity: The risk of hypertension is 5 times higher in the obese as compared to those of normal weight and up to two-thirds of cases can be attributed to excess weight. More than 85% of cases occur in those with a Body Mass Index (BMI)>25.
Sodium sensitivity: Sodium is an environmental factor that has received the greatest attention. Approximately one third of the essential hypertensive population is responsive to sodium intake. This is due to the fact that increasing amounts of salt in a person's bloodstream causes cells to release water (due to osmotic pressure) to equilibrate concentration gradient of salt between the cells and the bloodstream; increasing the pressure on the blood vessel walls.
Role of renin: Renin is an enzyme secreted by the juxtaglomerular apparatus of the kidney and linked with aldosterone in a negative feedback loop. The range of renin activity observed in hypertensive subjects tends to be broader than in normotensive individuals. In consequence, some hypertensive patients have been defined as having low-renin and others as having essential hypertension.
High Renin levels predispose to Hypertension: Increased Renin → Increased Angiotensin II → Increased Vasoconstriction, Thirst/ADH and Aldosterone → Increased Sodium Resorption in the Kidneys (DCT and CD) → Increased Blood Pressure. Some authorities claim that potassium might both prevent and treat hypertension.
Insulin resistance: Insulin is a polypeptide hormone secreted by cells in the islets of langerhans, which are contained throughout the pancreas. Its main purpose is to regulate the levels of glucose in the body antagonistically with glucagon through negative feedback loops. Insulin also exhibits vasodilatory properties. In normotensive individuals, insulin may stimulate sympathetic activity without elevating mean arterial pressure. However, in more extreme conditions such as that of the metabolic syndrome, the increased sympathetic neural activity may over-ride the vasodilatory effects of insulin. Insulin resistance and/or hyperinsulinemia have been suggested as being responsible for the increased arterial pressure in some patients with hypertension. This feature is now widely recognized as part of syndrome X, or the metabolic syndrome.
Sleep apnea: Sleep apnea is a common, under-recognized cause of hypertension. It is often best treated with nocturnal nasal continuous positive airway pressure, but other approaches include the Mandibular advancement splint (MAS), UPPP, tonsilectomy, adenoidectomy, sinus surgery, or weight loss.
Genetc disposition (Family history of high blood pressure): Hypertension can be caused by mutations in single genes, inherited on a mendelian basis. It is one of the most common complex disorders, with genetic heritability averaging 30%.citation needed. Data supporting this view emerge from animal studies as well as in population studies in humans. Most of these studies support the concept that the inheritance is probably multifactorial or that a number of different genetic defects each have an elevated blood pressure as one of their phenotypic expressions.
Ageing: Over time, the number of collagen fibers in artery and arteriole walls increases, making blood vessels stiffer. With the reduced elasticity comes a smaller cross-sectional area in systole, and so a raised mean arterial blood pressure.
Alcohol consumption can lead to a surge in blood pressure (no more than 1 to 2 drinks per day): People with hypertension or history of cardio-vascular disease should avoid liquorice raising their blood pressure to risky levels. Frequently, if liquorice is the cause of the high blood pressure, a low blood level of potassium will also be present. Liquorice extracts are present in many medicines (for example cough syrups, throat lozenges and peptic ulcer treatments).

Secondary hypertension

          Only in a small minority of patients with elevated arterial pressure can a specific cause be identified. In 90 percent to 95 percent of high blood pressure cases, the American Heart Association says there's no identifiable cause. For the rest (5-10%), most will probably have an endocrine or renal defect that, if corrected, could bring blood pressure back to normal values.
Renal hypertension: Hypertension produced by diseases of the kidney. This includes diseases such as polycystic kidney disease or chronic glomerulonephritis. Hypertension can also be produced by diseases of the renal arteries supplying the kidney. This is known as renovascular hypertension; it is thought that decreased perfusion of renal tissue due to stenosis of a main or branch renal artery activates the renin-angiotensin system.
Adrenal hypertension: Hypertension is a feature of a variety of adrenal cortical abnormalities. In primary aldosteronism there is a clear relationship between the aldosterone-induced sodium retention and the hypertension.
Cushing's syndrome: Both adrenal glands can overproduce the hormone cortisol or it can arise in a benign or malignant tumor. 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.
In patients with pheochromocytoma increased secretion of catecholamines such as epinephrine Coarctation of the aorta: The congenital abnormality aortic coarctation can result in hypertension.
Drugs: Certain medications, especially NSAIDs (Motrin/Ibuprofen) and steroids can cause hypertension. Licorice (Glycyrrhiza glabra) inhibits the 11-hydroxysteroid hydrogenase enzyme (catalyzes the reaction of cortisol to cortison) which allows cortisol to stimulate the Mineralocorticoid Receptor (MR) which will lead to effects similar to hyperaldosteronism, which itself is a cause of hypertension.
Rebound hypertension: High blood pressure that is associated with the sudden withdrawal of various antihypertensive medications. The increases in blood pressure may result in blood pressures greater than when the medication was initiated. Depending on the severity of the increase in blood pressure, rebound hypertension may result in a hypertensive emergency. Rebound hypertension is avoided by gradually reducing the dose (also known as "dose tapering"), thereby giving the body enough time to adjust to reduction in dose. Medications commonly associated with rebound hypertension include centrally-acting antihypertensive agents, such as clonidine and beta-blockers.
Pregnancy:   Although few women of childbearing age have high blood pressure, up to 10% develop hypertension of pregnancy. While generally benign, it may herald three complications of pregnancy: pre-eclampsia, HELLP syndrome and eclampsia. Follow-up and control with medication is therefore often necessary.

Hypertension in children and adolescents: As with adults, blood pressure is a variable parameter in children. It varies between individuals and within individuals from day to day and at various times of the day. The epidemic of childhood obesity, the risk of developing left ventricular hypertrophy, and evidence of the early development of atherosclerosis in children would make the detection of and intervention in childhood hypertension important to reduce long-term health risks; however, supporting data are lacking. Most childhood hypertension, particularly in preadolescents, is secondary to an underlying disorder. Renal parenchymal disease is the most common (60 to 70%) cause of hypertension. Adolescents usually have primary or essential hypertension, making up 85 to 95% of cases.

Pathophysiology of Hypertension

   The human body is integrated, dynamic, self-directed, and self-regulated. If the set-point of the chemical composition and physico-chemical properties of the internal environment (blood, lymph, interstitial and cerebrospinal fluids), as well as the physiological functioning of the body systems, is disturbed, a temporary cooperation (to solve this problem) is formed between body cells, tissues, organs, and even systems. If this union can not solve the homeostatic problem at hand, the dynamism of the body reorganises and forms another coopertation mentionend above. Modern conventional medicine recognises, as the initial trigger of high blood pressure, an imbalance between the sympathetic (symphaticus) and parasympathetic (parasymphaticus) divisions of the autonomic nervous system (vegetatika). An increase in the tone of thr symphaticus produces arteriolar vasoconstriction with a subsequent increase in the peripheral vascular resistance. At the onset, these changes exhibit a transient character and the body uses self-regulatory mechanisms (mentioned above) to restore the proper relationship between sympathetic and parasympathetic tones. This is why in earlier stages there are episodes of increased arterial blood pressure, without symptoms of hypertension. With time and repeated episodes of hypertension attacks, the body resets special receptors, called baroreceptors, in the arterial circulation to the new level, and the elevation of arterial blood pressure becomes sustained.
        So, balancing of the symphaticus and parasymphaticus , is a step forward, towards resolving the problems of hypertension.

Symptoms of High Blood Pressure

          There are usually no symptoms or signs of high blood pressure. In fact, nearly one-third of those who have it don't know it. The only way to know if you have high blood pressure definitely is to have your blood pressure checked. If your blood pressure is extremely high, there may be certain symptoms to look out for, including:
•    Severe headache
•    Fatigue or confusion
•    Vision problems
•    Chest pain
•    Difficulty breathing
•    Irregular heartbeat
•    Blood in the urine
          If you have any of the above mentioned symptoms, see a doctor immediately. You could be having a hypertensive crisis that could lead to a heart attack or stroke. Untreated hypertension can lead to serious diseases, including stroke, heart disease, kidney failure and eye problems.

Individuals that are more likely to develop hypertension
•    People with family members who have high blood pressure.
•    People who smoke, stop it.
•    Women who are pregnant.
•    Women who take birth control pills.
•    People over the age of 35.
•    People who are overweight or obese.
•    People who are not active. Strolling, for example, after morning prayers is always prophylactic.
•    People who drink alcohol excessively.
•    People who eat too many fatty foods or foods with too much salt.

NOTE: Eating white-bulbed onions with honey is a good prophylacsis against hypertension!!!

[eireen]

Yes I agree with you and now I modify my lifestyle. I am doing weight reduction, smoking cessation and I try to reduce my stress by relaxation therapy.