Blood Pressure – The height and the depth of the matter
High blood pressure or hypertension is regarded as one of the modern epidemics. It is perhaps one of the commonest diseases affecting mankind. Let us try and look at some of the issues on this subject.
Your blood pressure can change from minute to minute, with changes in posture, exercise or sleeping, but it should normally be less than 120/80 mm Hg for an adult. Blood pressure that stays between 120-139/80-89 is considered prehypertension and above this level (140/90 mm Hg or higher) is considered high (hypertension). Your doctor may take several readings over time before deciding whether your blood pressure is high.
What makes high blood pressure important?
It usually causes no symptoms but can still cause serious complications. Hence it is often called the "silent killer."
- Many people have high blood pressure and don't even know it.
- The key complications of high blood pressure include kidney failure, heart disease, heart attack, congestive heart failure, stroke, and peripheral artery disease, especially aortic aneurysms or outpouchings of the aorta.
- Public awareness of these dangers has increased. High blood pressure has become the second most common reason for medical visits in the United States.
- The only way to tell if you have high blood pressure is to have your blood pressure checked.
How common is it?
There is paucity of data from our country but data from the US suggest that as many as 1 billion people world wide have high blood pressure.
- That's about 1 in 3 adults aged 18 years and older. Yet nearly one-third of these people don't know they have it. If this true for th eland of the enlightened you can imagine the state in a country like ours.
- Studies done in US and UK suggest that the prevalence of hypertension in NRIs is much higher than native Caucasians.
- In India too with the changing lifestyle., increasing urbanization and Fats food culture there is an increasing prevalence.
- Uncontrolled high blood pressure is indirectly responsible for many deaths and disability resulting from heart attack, stroke, and kidney failure.
- However, good news is that the progress of heart disease as well as the kidney disease caused by high blood pressure can be slowed down by optimal blood pressue control.
How Do I Know If I Have High Blood Pressure?
High blood pressure usually has no symptoms. In fact, many people have this disease for years without knowing it. Having high blood pressure (hypertension) doesn't mean you're tense, nervous or hyperactive. You can be a calm, relaxed person and still have hypertension. The only way to find out if you have this disease is to have your blood pressure checked! A blood pressure test is quick and painless. It can be done in a doctor's office, hospital clinic, school, nurse's office, company clinic or at a health fair.
A single high reading doesn't mean you have high blood pressure, but it's a sign that you need to watch it carefully.
The mercury sphygmomanometer remains the most accurate way of measuring blood pressure. This device consists of a gauge and a rubber cuff that is placed around your arm and inflated. Having your blood pressure measured is painless and takes just a few minutes. If you are using electronic devices they need to be periodically cross calibrated with the mercury sphygmomanometer.
Causes of High Blood Pressure?
In about 10% of people, high blood pressure is caused by another disease (this is called secondary hypertension). In such cases, when the root cause is treated, blood pressure usually returns to normal. These causes include the following conditions:
- Chronic kidney disease
- Tumors or other diseases of the adrenal gland
- Coarctation of the aorta - A narrowing of the aorta that you are born with that can cause high blood pressure in your arms
- Alcohol addiction
- Thyroid dysfunction
In the other 90% of cases, the cause of high blood pressure is not known (primary hypertension). Although the specific cause is unknown, certain factors are recognized as contributing to high blood pressure.
What can we do to prevent developing high blood pressure?
- Overweight (obesity): is defined as being 30% or more over your healthy body weight. It is very closely related to high blood pressure. It is strongly recommended that all obese people with high blood pressure lose weight until they are within 15% of their healthy body weight. Your doctor can help you calculate your healthy range of body weight.
- Sodium (salt) sensitivity: Some people have high sensitivity to sodium (salt), and their blood pressure goes up if they use salt. Reducing sodium intake tends to lower their blood pressure. The typical Indian doiet contains very high sodium. Fast foods and processed foods contain particularly high amounts of sodium. Many over-the-counter medicines, such as painkillers, also contain large amounts of sodium. Read labels to find out how much sodium is contained in food items. Avoid those with high sodium levels.
- Alcohol use: Drinking more than 1-2 drinks of alcohol per day tends to raise blood pressure in those who are sensitive to alcohol.
- Birth control pills (oral contraceptive use): Some women who take birth control pills develop high blood pressure.
- Lack of exercise (physical inactivity): A sedentary lifestyle contributes to the development of obesity and high blood pressure. This is one of the most important reasons for an increasing incidence of hypertension.
- Drugs: Certain drugs, such as amphetamines (stimulants), diet pills, and some pills used for cold and allergy symptoms, tend to raise blood pressure.
As body weight increases, the blood pressure rises.
- Obese people are 2-6 times more likely to develop high blood pressure than people whose weight is within a healthy range.
- Not only the degree of obesity is important, but also the manner in which the body accumulates extra fat. Some people gain weight around their belly (central obesity or "apple-shaped" people), while others store fat around their hips and thighs ("pear-shaped" people). "Apple-shaped" people tend to have greater health risks than "pear-shaped" people and this pattern is gain more common in the Indian population.
Sometimes people with high blood pressure have the following symptoms:
- Blurred vision
People often do not seek medical care until they have symptoms arising from the organ damage caused by chronic (ongoing, long-term) high blood pressure. The following types of organ damage are commonly seen in chronic high blood pressure:
- Heart attack
- Stroke or "mini stroke" (transient ischemic attack, TIA)
- Kidney failure
- Eye damage with loss of vision
- Peripheral arterial disease, including outpouchings of the aorta called aneurysms
About 1% of people with high blood pressure do not seek medical care until the high blood pressure is very severe, also called malignant hypertension.
- In malignant hypertension, the diastolic blood pressure (the lower number) often exceeds 140 mm Hg.
- Malignant hypertension may be associated with headache, light-headedness, or nausea.
- This degree of high blood pressure requires emergency hospitalization and lowering of blood pressure to prevent brain hemorrhage or stroke.
It is of utmost importance to realize that high blood pressure can be unrecognized for years, causing no symptoms but causing progressive damage to the heart,kidney other organs, and blood vessels
When to Seek Medical Care?
Call your physician if a routine blood pressure measurement (during health screening) reveals systolic blood pressure higher than 140 mm Hg, diastolic blood pressure higher than 90 mm Hg, or both.
You also need an urgent consultation if you have any of the following symptoms:
- Unexplained severe headache
- Sudden or gradual changes in vision
- Light-headedness or dizziness
- Nausea associated with severe headache
- Chest pain or shortness of breath upon exertion
You need to let your doctor know if any family member has or has had high blood pressure, heart attack, stroke, or kidney failure.
Go to a hospital emergency department if your blood pressure is high when measured (for example, if your diastolic pressure is greater than 100 mm Hg).
Go to a hospital emergency department if you have any of the following symptoms:
- Severe headache
- Unexplained dizziness of faintness
- Unexplained blurred vision or loss of vision (partial or complete)
- Chest pain or breathlessness that is severe or occurs at rest
- Unexplained sudden weakness or other symptoms of stroke
The only way to tell whether you have high blood pressure is to have it measured with a blood pressure cuff .
Blood pressure (BP) is classified as follows:
- Normal BP - Systolic less than 120 mm Hg; diastolic less than 80 mm Hg
- Prehypertension - Systolic 120-139 or diastolic 80-89 mm Hg
- High BP
- Stage 1 - Systolic 140-159; diastolic 90-99 mm Hg
- Stage 2 - Systolic more than 160; diastolic more than 100 mm Hg
What investigations are a must?
Tests will be ordered to check for causes of high blood pressure and to assess any organ damage from high blood pressure or its treatment. These tests may include the following:
- Blood tests including measurement of electrolytes, blood urea, and creatinine levels (to assess kidney involvement)
- Lipid profile for levels of various kinds of cholesterol
- Special tests for hormones of the adrenal gland or thyroid gland
- Urine tests for electrolytes and hormones
A noninvasive, painless eye examination with an ophthalmoscope will look for ocular damage.
Ultrasound of the kidneys, CT scan of the abdomen, or both may be done to assess damage or enlargement of the kidneys and adrenal glands.
Any of the following may be performed to detect damage to the heart or blood vessels :
(1) Electrocardiogram (ECG) is a noninvasive test that detects the electrical activity of the heart .
- Echocardiogram is an ultrasound examination of the heart taken through the chest. Sound waves take a picture of the heart as it beats and relaxes and then transmits these images to a video monitor. The echo can detect problems with the heart such as enlargement, abnormalities in motion of the heart wall, blood clots, and heart valve abnormalities. It also gives a good measurement of the strength of the heart muscle (ejection fraction). The echo is more accurate than an ECG, but also more expensive.
- A plain chest x-ray primarily provides an estimate of the size of the heart, but it is much less specific than echocardiography, which looks inside the heart.
Blood Pressure – the height an depth of the issue - Part II
High Blood Pressure Treatment
Management of blood pressue is a team work between you and and your doctor. There are various options for treating your high blood pressure.
- Many people can lower their blood pressure significantly with lifestyle changes, such as weight loss and exercise, but most still need medication to keep their blood pressure in the healthy range.
- Whichever therapy you choose, it is important to have your blood pressure checked regularly to make sure that your treatment is working.
- Uncontrolled high blood pressure is a leading cause of heart disease, heart attacks, heart failure, kidney failure, vision problems, and stroke.
- Measure your blood pressure three times, 2 minutes apart. The third measurement is usually the most accurate.
- If your blood pressure is high on the third reading, even borderline, have it checked by another machine that you know is accurate (for example, at your health care provider).
- Do not rely on the machines in stores alone to check your blood pressure. Have it checked regularly by a trained medical professional with a machine that is known to be accurate.
What can I do at home for myself ?
The management and control of high blood pressure involves 2 major options, lifestyle modification (detailed here) and medications .
Lifestyle options include changing what you eat and your activity level.
- Quitting smoking and moderating alcohol consumption will also help keep your blood pressure in the healthy range.
Maintain a healthy weight.
- If you are overweight or obese, lose weight. Aim for a healthy weight range for your height and body type. Your health care provider can help you calculate a target weight.
- Even a small amount of weight loss can make a major difference in lowering or preventing high blood pressure.
- To lose weight, you must burn more calories than you take in.
- Crash or fad diets are not helpful and may be dangerous.
- Some weight loss medications also carry major risks, and great caution is advised in using these drugs.
- The healthiest and longest-lasting weight loss requires slow loss, such as losing one-half to 1 pound each week. Eating 500 calories less than you burn every day may help achieve this goal. In a week, you will eat 3500 calories less than you burn, which is enough to lose 1 pound.
- Increasing your physical activity will help you burn more calories.
Lose weight and keep it off.
- Choose foods low in calories and fat. Fat is a concentrated source of calories. You should cut down on butter, margarine, regular salad dressing, fatty or red meats, the skin of poultry, whole milk, cheese, fried foods, ice cream, many cookies, cakes, pastries, and snacks.
- Choose foods high in starch and fiber: These foods are low in fat and also good sources of vitamins and minerals. Try fruits, vegetables, whole-grain cereals, rice, and dry peas and beans.
- Limit serving sizes: You should especially try to take smaller helpings of high-calorie foods such as meats and cheeses. Try to avoid the temptation of going back for seconds.
- Write down what you eat and when: It may be helpful to track your habits. You should note where you are and what you are doing when you snack on high-calorie foods. For instance, many people snack while watching television. Or do you skip breakfast and then eat a large lunch? Identifying your eating patterns can help you overcome the situations in which you overeat.
Exercise or increase physical activity.
- Physical activity burns calories, helps you lose weight, and reduces stress.
- Physical activity reduces total cholesterol and bad cholesterol (LDL) and raises the good cholesterol (HDL).
- A minimum of at least 30 minutes of exercise every other day is recommended.
- Physical activity doesn't have to mean running a marathon. House cleaning or playing golf or baseball can burn as many as 300 calories per hour; brisk walking (at 3.5 mph), cycling (at 5.5 mph), gardening, dancing, or playing tennis l burns as many as 450 calories per hour; jogging (9 min/mile), playing football, or swimming can burn as many as 730 calories per hour; and running (7 min/mile), can burn as many as 920 calories per hour.
- You can fit physical exercise into your daily routine.
- Practice yoga and/or meditation. These ancient Indian techniques have now even achieved great popularity in the West.
- Use the stairs instead of the elevator.
- Get off the bus 1 or 2 stops early and walk the rest of the way.
- Park your car farther away from the office or the shopping centre.
- Ride a bike.
- Work in the garden.
- Wash the car the old-fashioned way.
General tips for controlling blood pressure include the following:
- Reduce sodium (salt) intake.
- Limit alcohol to no more than 2 drinks a day.
- Quit smoking.
- Take medicines as directed.
What are the types of medications that can be used ?
Medication is an important part of blood pressure control for almost everybody with high blood pressure. Many people cannot keep their blood pressure in the healthy range by lifestyle changes alone.
- Only 21% of people with high blood pressure are on blood pressure medicines and have their pressure adequately controlled.
- At least 16% of people with high blood pressure are not on any medication.
- Approximately 28% are taking medicines incorrectly, and their blood pressure is uncontrolled.
- Therefore, the biggest challenge in the treatment of high blood pressure is taking the medication correctly.
high blood pressure, limiting sodium intake by eliminating table salt, cooking salt, and salty and processed foods can reduce blood pressure by 5 mm Hg. Losing weight and doing regular physical activity can reduce the blood pressure further.
If these lifestyle changes and choices don’t work, medications should be added. The medications have been proven to reduce the risk of stroke, heart disease, and kidney problems. Do not stop taking your medications without talking to your health care provider.
Medications most often prescribed for high blood pressure include the following:
Water pills (diuretics)
- Diuretics are used very widely to control mildly high blood pressure, and in combination with all other medications that they have a greater effect with. They are especially relevant for our country in view of their low cost.
- They increase sodium excretion and urine output and decrease blood volume. The sensitivity to the effect of other hormones in your body is decreased.
- Example - Hydrochlorothiazide (HydroDIURIL)
- Beta-blockers reduce heart rate and decrease the force of heart contraction, thereby reducing the pressure generated by the heart.
- They are preferred in people who have associated coronary heart disease, angina, or history of a heart attack, since they also prevent recurrent heart attacks and sudden death.
- Examples - metoprolol , atenolol.
- Side effects - Fatigue, depression, impotence, nightmares
Calcium channel blockers
- Calcium channel blocking agents work by relaxing the muscle in the walls of the arteries.
- They also reduce the force of contraction of the heart.
- Examples - Nifedipine , diltiazem , verapamil , amlodipine.
- Side effects - Ankle swelling, fatigue, headache, constipation, flushing
Angiotensin-converting enzyme (ACE) inhibitors
- ACE inhibitors stop the production of a chemical called angiotensin II, a very potent chemical that causes blood vessels to contract, a cause of high blood pressure. Blockage of this chemical causes the blood vessels to relax.
- Examples - Captopril , enalapril , lisinopril, ramipril
- Side effects are infrequent but sometimes they can worsen kidney function and raise the serum potassium, especially in patients with damaged kidneys. ACE inhibitors sometimes cause dry cough and rarely angioedema or severe swelling around your trachea/windpipe.
Angiotensin receptor blockers or ARBs
- ARBs work on receptors in tissues all over the body to prevent uptake of angiotensin II, and therefore inhibit the vasoconstrictor effect of angiotensin II.
- Examples - Losartan , valsartan
- Side effects tend to be less with ARBs than ACEIs with much less cough.
- Alpha-blockers relax blood vessels by blocking messages from the nervous system that cause muscular contraction.
- Examples - Terazosin , doxazosin
- Since publication of ALLHAT trial in 42,000 patients, and premature termination of the alpha-blocker arm because of excessive incidence of congestive heart failure, alpha-blockers are not used as much any more, just primarily in men with associated prostatism symptoms.
Blockers of central sympathetic (autonomic nervous) system
- These agents block messages out of the brain from the autonomic nervous system that contract blood vessels. The autonomic nervous system is the part of the nervous system that is automatic and controls heart rate, breathing rate, and other basic functions.
- Their effect is to relax blood vessels, thus lowering blood pressure. These agents are not as popular because of excessive side effects and no randomized trials demonstrate their effectiveness in lowering heart attacks, strokes, etc.
- Example - Clonidine
- Direct vasodilators relax (dilate) the blood vessels to allow blood to flow under lower pressure.
- These medications are often given through an IV line in an emergency (that is, in malignant hypertension).
- Examples - Nitroprusside , diazoxide . Oral medications are hydralazine and minoxidil.
When is surgery indicated ?
Rarely, surgery is needed to remove benign, hormone-producing tumors of the adrenal gland. If a narrowing of a renal artery is discovered, sometimes a balloon dilatation, followed by placement of a metal stent, is done in the invasive vascular laboratory.
- Most of these substances are harmless if taken in moderate doses. Most people can take them without problems.
- Talk to your health care provider if you are considering any of these treatments. Substituting these therapies for medical therapies that have been shown to lower blood pressure and the risk of complications may have a harmful effect on your health.
What Follow-up is recommended?
The most important element in the management of high blood pressure is follow-up care.
- Check with your health care provider periodically to make sure that your blood pressure is in the recommended range. If it is not, your treatment should be adjusted.
- If you are diabetic or have had a prior heart attack or stroke, your doctor may want your blood pressure lowered to 125-130 mm HG to prevent recurrent events.
- With aging and progression of the process of hardening of the arteries, your systolic blood pressure may creep up with time. A treatment that once worked well may no longer work as well. Your drug dosage may need to be changed or you may be prescribed a new medication.
- At your follow-up visits, you should be screened for damage to the heart, eyes, brain, kidney, and peripheral arteries that may be related to high blood pressure.
- Follow-up visits are a good time to let your health care provider know about any side effects you are having from your medication. He or she will have suggestions for coping with side effects or may change your treatment.
- Follow-up visits are a great opportunity for monitoring for other associated risk factors, such as high cholesterol and obesity.
What preventive strategies are recommended?
Prevention is better than cure is the age old adage and this certainly holds true for hypertension too. The following strategies may help to prevent high blood pressure and organ damage it may cause.
- Eat a nutritious, low-fat diet.
- Exercise regularly.
- Decrease salt (sodium) intake: Read food labels so you know the salt content before you buy a product in the grocery store.
- Maintain a healthy weight: If you are overweight or obese, try to lose weight.
- Use alcohol in moderation, if at all.
- Stop smoking.
- Get your blood pressure checked periodically. Consider getting an accurate and easy-to-use home monitor.
- Take your blood pressure medications as directed, even if you’re feeling fine.
- Reduce stress and practice relaxation: Physical activity will help with this.
What is the long term outcome?
Your prognosis is usually good if your blood pressure is controlled.
- Chances are you will take blood pressure medications the rest of your life, unless you make dramatic changes in your lifestyle.
- The sad fact, however, is that high blood pressure is adequately treated in only one fifth of the 60 million Americans who have it.
- Moreover, 35% of people with high blood pressure don't know they have it.
- Untreated high blood pressure is one of the most common causes of heart enlargement and heart failure, heart attack, stroke, and kidney failure. That is why high blood pressure is called "the silent killer."