Control Your Blood Pressure

A. N. Khan*

The World Health Day 2013 theme is 'High Blood Pressure' or Hypertension. It increases the risk of heart attacks, strokes and kidney failure and if left uncontrolled, it can also cause blindness, irregular heart beat and heart failure, rupture of blood vessels and brain impairment. It affects one in three adults and leads to more than nine million deaths every year worldwide.

The heart is a wonderful organ, working day and night, without rest, beating approximately 70 times/ minute, 100,000 times/day. It drives the blood through thousands of km blood vessels to nourish each and every cell in our body. The flow of blood to and from the heart is kept moving in the correct direction by the opening and closing of the appropriate valves. The 'Lab-dub' sound heard through the stethoscope is due to the movements of valves.

Hypertension or high blood pressure (BP), accelerates arteriosclerosis which narrows the arteries and impedes the flow of blood to the heart or brain causing heart attack or strokes. In the early stages of the high BP there are no symptoms. Many, who are afflicted, feel no discomfort until a medical crisis – a heart attack or stroke occurs. As a consequence, high BP is often referred to as the 'Silent Killer'.

Sudden death was recognized as early as 5^th century B.C. by the Greek physician,Hippocrates and was noted to be more common in obese. It was not until William Harvey discovered the true nature of circulation of blood in 1628 that the background for more understanding was established. Stephen Hales was the first to measure arterial blood pressure in 1733. Antemortem diagnosis made little progress until Rene Lacnnec invented the stethoscope in 1819. Richard Jr. Dikinson and Forssmann in 1956 invented a technique called catheterization, enabling the physician to look into the various blood vessels serving the heart, to assess the extent of blockage and also examine proper functioning of the valves.

Feodor Lynen in 1964 discovered how cholesterol is formed from human cells, investigated lipid metabolism in the body and enabled medical science to find ways of arresting abnormal growth of fat in blood. Michael Brown and Joseph Goldstaindiscovered in 1985, how the low density Lipo-protein (LDL), receptor, a protein molecule which ferries  particles rich in cholesterol from the blood to the cells, settle inside blood vessels, supplying blood to the heart, signals the possibility of heart attack.

Hypertension is diagnosed if readings on separate occasions consistently show systolic blood pressure to be 140 and diastolic blood pressure 90 mmHg or higher. The risk of developing complications is higher in the presence of other cardio-vascular risk factors such as diabetes. One in three adults worldwide has hypertension, the proportion increases with age – 1 in 2 persons in the 50s age group.

Cardio-vascular diseases (CVD) are killing more and more people around the world, striking rich and poor alike. Those who survive a heart attack or stroke often need to take long-term medical treatment. These diseases can seriously affect the life of both the patient and his or her family.

High BP is preventable, and can be countered by reducing salt intake, eating a balanced diet, avoiding the harmful use of alcohol, taking regular physical activity, maintaining a healthy body weight and avoiding tobacco use.

Reducing salt intake is a crucial factor in lowering the risk of CVD. In many countries more than 2/3^rd of all salt consumed is hidden in processed foods and snacks or food products such as bread and cheese. In addition some fast food chains and restaurants are key suppliers of food high in salt as well as fats and sugars. This means that only approximately 20% of salt intake is under the control of consumer. WHO recommends an intake of less than 5 g/day (1 teaspoon of salt/day) to avoid CVD.

A balanced diet is crucial to a healthy heart and circulation system. This should include plenty of fruits and vegetables, whole grains, lean meat, fish and pulses and restricted salt, sugar and fat intake.

At least 30 minutes of regular physical activity everyday helps to maintain CV fitness.

Tobacco in every form is harmful to health – cigarettes or chewable tobacco. Exposure to second-hand tobacco smoke is also dangerous.

In every region of the world, obesity doubled between 1980 and 2008. Today half a billion people i.e., 12% of the world's population are considered obese. In all parts of the world women are more likely to be obese than men, and thus at greater risk of diabetes and CVD.

One in three adults worldwide have raised BP – a condition that causes around half of all deaths from stroke and heart disease. It is considered directly responsible for 7.5 million deaths in 2004 – almost 13% of all global deaths. In nearly all high income countries, widespread diagnosis and treatment with low-cost medication have led to a dramatic drop in mean BP across populations – and this has contributed to a reduction in deaths from heart disease. For example in 1980 almost 30 and 40% of adults in the WHO Region of America and European Union have had high BP. By 2008, this dropped to below 23 and 30% respectively. In contrast, in the WHO African region, more than 40 to 50% of adults in many countries are estimated to have high BP and this proportion is increasing. WHO estimates that more than 7.3 million people died of CVD in 2008.

Many people with high BP in developing countries remain undiagnosed, and so miss on treatment that could significantly reduce their risk of death and disability from heart disease and stroke.

For many people life style changes are sufficient to control BP, for others medication is required. It is essential that detection and control of high BP, are coupled with other risk factors, such as diabetes and tobacco use.

Current data suggest that the effect of 'aspirin' in reducing the risk of coronary disease is even greater than that of cholesterol lowering drugs. Aspirin is given to certain patients as a preventive measure whose LDL cholesterol level is continuously high.

The role of antioxidants such as 'Vitamin E', 'Vitamin C' is gaining momentum in preventing the progress of arteriosclerosis. Many naturally occurring anti-oxidants, helpful to the body, are present in garlic and onion, consumption of the same in the regular diet is also helpful.

(PIB Feature.)

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World Health Day - 7^th April, 2013.

Disclaimer: The views expressed by the author in this feature are entirely his own and do not necessarily reflect the views of PIB.

*Senior Scientist & Former Asst. Director, NEERI, Nagpur.

Source:-PIB