Hypertension, also known as high blood pressure is the force of blood pushing against the walls of arteries as it flows through them. Arteries are the blood vessels that carry oxygenated blood from the heart to the body’s tissues.
As blood flows through arteries it pushes against the inside of the artery walls. The more pressure the blood exerts on the artery walls, the higher the blood pressure will be. The size of small arteries also affects the blood pressure. When the muscular walls of arteries are relaxed, or dilated, the pressure of the blood flowing through them is lower than when the artery walls narrow, or constrict.
Blood pressure is highest when the heart beats to push blood out into the arteries. When the heart relaxes to fill with blood again, the pressure is at its lowest point. Blood pressure when the heart beats is called systolic pressure. Blood pressure when the heart is at rest is called diastolic pressure. When blood pressure is measured, the systolic pressure is stated first and the diastolic pressure second. Blood pressure is measured in millimeters of mercury (mm Hg).
Hypertension is having a blood pressure higher than 140 over 90 mmHg, a definition shared by all the medical guidelines. This can damage the blood vessels and cause health problems. Anyone can develop high blood pressure, but it becomes more common as you get older.
Hypertension is a major health problem, especially because it has no symptoms. Many people have hypertension without knowing it. In the United States, about 50 million people age six and older have high blood pressure. Hypertension is more common in men than women and in people over the age of 65 than in younger persons. More than half of all Americans over the age of 65 have hypertension. It also is more common in African-Americans than in white Americans.
Hypertension is serious because people with the condition have a higher risk for heart disease and other medical problems than people with normal blood pressure. Serious complications can be avoided by getting regular blood pressure checks and treating hypertension as soon as it is diagnosed. Hypertension makes the heart work harder to pump blood through the body. The extra workload can make the heart muscle thicken and stretch. When the heart becomes too enlarged it cannot pump enough blood. If the hypertension is not treated, the heart may fail.
Risk Factors
- People with close blood relatives who have HBP
- African Americans
- Overweight or Age – Everyone is at greater risk of high blood pressure as they get older. Prevalence of hypertension is higher in people over 60 years of age
- Race – African-American adults are at higher risk than white or Hispanic American adults
- Size – Being overweight or obese is a key risk factor
- Sex – Men and women have different risk profiles. While they have the same lifetime risks, men are more prone at younger ages while women are more prone at older ages
- Lifestyle – As mentioned above, this is to blame for growing rates of hypertension, from greater uptakes of dietary salt, excessive alcohol, low dietary potassium, and physical inactivity.gout or kidney disease
- Pregnant women
- Women who take birth control pills, who are overweight, had HBP during pregnancy, have a family history of HBP or have mild kidney disease.
In general, the older you get, the greater your chance of developing HBP.
Causes
There are two types of Hypertension –
Essential Hypertension – In as many as 95% of reported high blood pressure cases in the U.S., the underlying cause cannot be determined. This type of high blood pressure is called essential hypertension. This is caused by –
- Genetics and Family History – When members of a family pass traits from one generation to another through genes, that process is called heredity.
- Genetic factors likely play some role in high blood pressure, heart disease, and other related conditions. However, it is also likely that people with a family history of high blood pressure share common environments and other potential factors that increase their risk.
- The risk for high blood pressure can increase even more when heredity combines with unhealthy lifestyle choices, such as smoking cigarettes and eating an unhealthy diet.
- Unhealthy Diet – A diet that is too high in sodium and too low in potassium puts you at risk for high blood pressure. Eating too much sodium—an element in table salt—increases blood pressure. Most of the sodium we eat comes from processed and restaurant foods. Learn more about sodium and high blood pressure.
- Not eating enough potassium also can increase blood pressure. Potassium is found in bananas, potatoes, beans, and yogurt.
- Physical Inactivity – Not getting enough physical activity can make you gain weight, which can lead to high blood pressure.
- Obesity – Obesity is excess body fat. Obesity is linked to higher “bad” cholesterol and triglyceride levels and to lower “good” cholesterol levels. In addition to high blood pressure, obesity can also lead to heart disease and diabetes. Talk to your health care team about a plan to reduce your weight to a healthy level.
- Too Much Alcohol – Drinking too much alcohol can raise your blood pressure.
- Tobacco Use – Tobacco use increases your risk for high blood pressure. Cigarette smoking can damage the heart and blood vessels. Also, nicotine raises blood pressure, and carbon monoxide reduces the amount of oxygen that your blood can carry.
Secondary Hypertension – Secondary hypertension has specific causes – that is, it is secondary to another problem. One example, thought to be the most common, is primary aldosteronism, a hormone disorder causing an imbalance between potassium and sodium levels and so high blood pressure. Common reversible causes are excessive intake of alcohol and use of oral contraceptives, which can cause a slight rise in blood pressure; hormone therapy for menopause is also a culprit.7 Other secondary hypertensions are caused by –
- Kidney disease
- Pheochromocytoma (a cancer)
- Cushing syndrome (which can be caused by use of corticosteroid drugs)
- Congenital adrenal hyperplasia (disorder of the adrenal glands, which secrete the hormone cortisol)
- Hyperthyroidism (overactive thyroid gland).
Symptoms
High blood pressure itself is usually experienced by patients without any symptoms at all (asymptomatic). It can do its damage silently.
Hypertension can lead to problems in the organs affected by high blood pressure. Long-term hypertension can lead to the following complications via arteriosclerosis, which causes narrowing of blood vessels by forming plaques –
- An enlarged or weakened heart, to a point where it may fail to pump enough blood (heart failure)
- Aneurysm – an abnormal bulge in the wall of an artery
- Blood vessel narrowing – in the kidneys, leading to possible kidney failure; also in the heart, brain and legs, leading to potential heart attack, stroke or amputation, respectively
- Blood vessels in the eyes my rupture or bleed, leading to vision problems or blindness (hypertensive retinopathies, which can be classified by worsening grades one through four).
Treatment
Medications – Drugs currently used to treat hypertensive emergencies include nicardipine, labetalol, and sodium nitroprusside.
Many antihypertensive drugs are available for the treatment of chronic hypertension. The choice of drug is usually based on the mode of action and the potential for adverse effects. From a pharmacologic point of view, antihypertensive drugs may be classified in the following categories –
- Diuretics, which block sodium reabsorption at various levels of the renal tubules
- Adrenergic blockers, which act by competitively inhibiting the catecholamines
- Direct vasodilators, which act by means of various mechanisms
- Angiotensin-converting enzyme (ACE) inhibitors, which block the conversion of angiotensin I to angiotensin II
- Angiotensin II receptor blockers (ARBs), which interfere with the binding of angiotensin II to angiotensin I receptors
- Calcium-channel blockers, which block the entry of calcium into the cells, producing vasodilation
Lifestyle changes that may reduce blood pressure by about 5 to 10 mm Hg include –
- Reducing salt intake
- Reducing fat intake
- Losing weight
- Getting regular exercise
- Quitting smoking
- Reducing alcohol consumption
- Managing stress
Alternative Treatment
Fish Oils are useful for thinning the blood and improving circulation and it is now known that those whose diets are high in fish oils have a lower risk for hypertension. It helps to lower the risk for hypertension.
Potassium is helpful in hypertension. Those who have low potassium levels are more likely to have high blood pressure.
Magnesium levels have been found to be consistently low in individuals with hypertension. In one study, supplemental magnesium lowered blood pressure in 19 out of 20 hypertensives.
The non-essential amino acid L-Taurine may exhibit hypotensive properties. However, the doses utilized to reap hypotensive results vary widely in the studies.
CoQ10 – High CoQ10 dosages could lead to shallow sleep which is not helpful since deep sleep reduces hypertension risk. Among antioxidants, coenzyme Q10 (CoQ10) stands out for its ability to promote healthy blood pressure levels.
Vitamin D – Blood pressure reduction is one of the many extraordinary health benefits of vitamin D. People deficient in vitamin D are more likely to have high blood pressure.48,49 Vitamin D supplementation, alone or with calcium, can reduce blood pressure in people with hypertension.50,51 Vitamin D likely exerts this effect in part by suppressing the expression of the blood pressure hormone renin, similar to the effect of prescription angiotensin-converting enzyme (ACE) inhibitors.
Garlic – The compounds found in garlic help regulate the immune response involved in the inflammatory process and have been shown to lower lipid levels.
Folic acid – Folic acid is sometimes given as an alternative treatment for hypertension because of its effects on the arterial walls. There is some evidence that accumulation of the amino acid homocysteine in the blood can damage these walls. Folic acid, typically given in combination with vitamins B6 or B12, reduces homocysteine levels.
Alpha-Linolenic Acid (ALA) – ALA is a type of omega-3 fatty acid found in plants such as flax and walnuts.
Docosahexaenoic Acid (DHA) and Eicosapentaenoic Acid (EPA) – Similar to ALA, these essential fatty acids may decrease blood pressure slightly.
Fiber/Psyllium – The Journal of the American Dietetic Association reports that replacing refined carbohydrates with whole grains that contain high amount of fiber reduces blood pressure.
Calcium – Those with low calcium seem to be at higher risk for hypertension. The exact relationship between calcium and high blood pressure is unknown, but ensuring proper intake of calcium is helpful.
Flavonoids – Flavonoids are compounds found in high concentrations in tea, cocoa, wine, and grapes. They also appear to have beneficial effects when it comes to lowering blood pressure.
Folate – Women with an increased dietary or supplement-based intake of folate have been shown to have a lower incidence of hypertension.