High blood pressure (hypertension) is one of the leading causes of kidney failure. It is a disease that, on the surface, seems harmless because there may be little to no symptoms. However, if it goes undetected and/ or untreated for an extended period, the effects could be deadly... Hence the reason it is commonly referred to as "the silent killer".
High blood pressure not only affects the kidneys but can also severely damage other organs and tissues in the body, and increases the risk of developing kidney failure, vision loss, congestive heart failure, heart attack, stroke, and other serious complications.
High blood pressure affects one in every four adults in developed western societies, and almost 30% of those people affected by hypertension are not even aware that they have this disease. Unfortunately, of the 70% who know they have hypertension, almost 40% of them are being inadequately treated, and another 20% are receiving no treatment at all. This indicates that a large percentage of our populations are at risk of developing life threatening conditions, associated with high blood pressure.
If high or elevated blood pressure remain untreated for an extended period, it can eventually begin to affect kidney function resulting in kidney failure. It is therefore, considered a cause of renal failure.
The kidneys play an important role in regulating blood pressure. If kidney function becomes impaired, the kidneys may not be able to effectively keep blood pressure within the normal range. It is therefore, also a symptom of kidney failure.
Blood pressure is the force that the blood exerts against a vessel wall. Pressure is often measured by observing how high it can push a column of mercury [Hg] up an evacuated tube called a sphygmomanometer.
It is normally measured at the brachial artery of the arm (usually left arm). This artery is sufficiently close to the heart to reflect the maximum arterial blood pressure found anywhere in the systemic circuit.
Sphygmomanometers provide very accurate blood pressure readings and are likely to be used by your doctor. While the average person may not have access to a sphygmomanometer, there are other reliable devices that can be used to monitor blood pressure at home.
The most common device that can be used at home to measure blood pressure is the digital blood pressure monitor.
Digital blood pressure monitors use digital technology to provide blood pressure readings that are reasonably accurate and easy to understand. These devices are relatively inexpensive, easy to use and are widely available.
It is advisable for patients who have been diagnosed with high blood pressure to obtain one of these devices, in order to regularly monitor their blood pressure. Your doctor or pharmacist should be able to recommend a suitable blood pressure monitor for you.
Two pressures are recorded: systolic pressure and diastolic pressure. Systolic pressure is the peak arterial blood pressure attained when the heart beats, and diastolic pressure is the minimum blood pressure between heartbeats. Because pressures are compared to the force generated by a column of mercury, they are expressed in terms of millimeters of mercury [mmHg].
For a healthy person the systolic and diastolic pressures are typically about 120 and 75 mmHg, respectively. Arterial blood pressure is written as a ratio of systolic over diastolic pressure. So, the blood pressure of a typically healthy person is written as 120/75.
A chronic (long term) resting blood pressure that is consistently higher than 140/90 is commonly classified as hypertension. (Transient high blood pressure resulting from emotion or exercise is not hypertension.)
When blood pressure is constantly elevated, this places a lot of stress on the kidneys' arterioles (small arteries). They thicken in response to the stress, their passage-way (lumens) becomes smaller and blood flow declines.
When the kidneys detect a decline in blood flow, they release renin (an enzyme secreted by the kidneys which activates hormonal mechanisms that control blood pressure and electrolyte balance). This reaction by the kidneys causes blood pressure to increase, thus contributing to hypertension.
Most cases of high blood pressure result from lifestyle, dietary, hereditary factors, and other factors. In these cases, however, it is difficult to pinpoint the specific underlying cause(s). These cases are known as primary hypertension and account for approximately 90% of all cases. In former years, it was considered to be a normal part of aging and was (and continues to be) called essential hypertension.
This may seem to suggest that it is normal and cannot be avoided, but this is not necessarily so. Having an understanding of the primary causes of hypertension can help in formulation of effective preventative strategies.
Treatments for primary hypertension include weight loss, diet, exercise, natural and homeopathic products, and certain prescription drugs. Within recent years, the trend has been to use more alternative and natural treatments, rather than prescription drugs. Some of these natural and alternative products have been quite successful, without the side effects of traditional prescription medicines. In some cases, however, both alternative and traditional treatments may be required, to effectively lower blood pressure.
Secondary hypertension is high blood pressure that is caused by another medical condition, and accounts for approximately 10% of cases. Examples of identifiable disorders that can cause high blood pressure include:
Secondary hypertension is corrected by treating the underlying causes.
The effects of hypertension on the tissues and organs of the body can be severe. Tens of millions of people are walking around with uncontrolled high blood pressure.
Over time, this silent killer weakens the arteries, stresses the heart, corrodes arteries in the brain, threatens the eyesight, and eats away at the kidneys. The excess force generated by the constant high pressure of the blood against blood vessel walls can damage their all-important lining (the inner lining of arteries is called the endothelium). Damage to the endothelium speeds up the hardening of the arteries.
Hardening of the arteries, known as atherosclerosis, is a condition that affects us all as we grow older. High blood pressure, however, speeds up this process considerably. These stiffened, narrow arteries have a hard time supplying the body with enough oxygen and nutrients, which means the tissues and organs that they serve can be damaged.
If the arteries in your eye are affected, your vision may suffer; if the arteries in your kidneys are damaged, you may develop kidney disease or kidney failure; if the arteries in your heart are damaged, you could develop blockages that can cause a heart attack; and if arteries in your brain are affected, blockages may occur that can trigger a stroke.
High blood pressure, whether primary or secondary, is a serious health condition. It is a major cause of strokes, heart failure and kidney failure. Your best defense against high blood pressure is to prevent it, by minimizing and avoiding the risk factors and causes, and treating any underlying condition which may cause it. Visit your doctor regularly and purchase a blood pressure monitor to check your blood pressure regularly. Also very importantly, eat a balanced diet, drink adequate amounts of water, exercise regularly, reduce stress levels, and avoid destructive lifestyle habits, such as smoking.