HIGH BLOOD PRESSURE

YOUR HEART IS AN ENGINEERING marvel: an elegant pump that receives oxygen-rich blood from the lungs and uses just the right amount of force to push it back through the arteries and out to the body's tissues.
When all goes well,.there is just enough pressure inside the arteries to maintain a steady flow of blood. But such pressure can be affected by exercise, stress, diet and hormones, as well as by blood loss from menstruation or severe injury.

To keep the system working correctly in the face of constantly changing conditions, the heart makes continual adjustments. Its rate of beating speeds up or slows down, and the strength of its contractions increases and decreases. At the same time arteries relax and dilate or contract and constrict, and the kidneys either retain salt and water (thus raising blood pressure) or release salt and water (allowing blood pressure to drop).

Given the intricacy of the circulatory system, it's no surprise that chronically elevated blood pressure, or hypertension, is one of the most common of all diseases, affecting millions of people in Western societies. It's even more common among people of certain ethnic backgrounds, for reasons that remain unclear.

The trouble with high blood pressure is that it's symptomless. It can hang around for 10 to 20 years, damaging vital organs such as the brain, kidneys and eyes, without giving you any clues that you have it.
Massive public health measures have been initiated to identify and treat people affected by high blood pressure, but figuring out whether you're one of them is not always easy. In some people, blood pressure readings can vary by 20 to 60 points in the course of a day. And many people notice that their blood pressure tends to increase in a doctor's surgery, a phenomenon called white-coat hypertension.

FIRST THINGS FIRST
Drugs to lower blood pressure are among the most frequent reasons a doctor gets out a prescription pad. Although these drugs are usually effective, their value is diminished by side effects such as fatigue and depression. They can also impair your ability to exercise or to enjoy sex. Therefore, if you've been newly diagnosed with high blood pressure, you'll probably want to ask your doctor if you can avoid having to take such drugs by making some changes in your lifestyle.
Fortunately, because so many people suffer from high blood pressure, a great deal of research has been done on ways to fight the disorder. Stress management techniques that have been proven to help include meditation, biofeedback and regular aerobic exercise. Losing weight and decreasing alcohol consumption may also have a big impact. Some people, especially those with type 2 diabetes, find that restricting carbohydrates can dramatically lower their blood pressure.

A SALTY DEBATE
It used to be a sure thing that you'd be told to give up salt if you had high blood pressure. More current research, however, has shown that reducing sodium helps lower blood pressure for less than half of those who try it.
On the other hand, most people do eat too much salt - a daily average
of 2 to 3 teaspoons - and would benefit by cutting back to 1 teaspoon. A
simple way to do this is to stop adding extra salt to food.

DOING THE BLOOD-PRESSURE NUMBERS
Blood pressure measures how much the heart contracts (systolic pressure) and how much the arteries contract (diastolic pressure). Although a reading
of 140 (the systolic number) over 90 (the diastolic number) is designated as
the upper limit of normal for people in industrialised societies, comparative studies of other populations suggest these figures may be too high. For example, the Tarahumara Indians of Mexico, who have a very active lifestyle, often walking or running several kilometres daily up and down steep canyon
walls, have an average blood pressure of 90 over 60 and a much lower rate
of heart attacks and strokes than Europeans and Americans.
Instead of waiting until your blood pressure reaches someone else's arbitrary limit and then trying to lower it after the fact, a better strategy is to keep an eye on this barometer of health on a regular basis. Experts suggest beginning intervention on a number of fronts - diet, exercise and natural
remedies - when readings regularly exceed 120 over 80. Blood pressure should be checked once a year if normal, and four times a year if it is ever found to be elevated.

DRUG TREATMENT

Beta Blockers
Propranolol (Inderal), betaxolol (Kerlone), carvedilol (Eucardic), atenolol (Tenormin), metoprolol (Betaloc, Lopresor), labetolol (Trandate). Function: block chemical processes that lead to increased
heart pressure and heart rate; often given after a heart attack. Side effects:
tiredness, excessively slow heart rate, impaired sexual functioning; dramatic increases in blood pressure upon sudden discontinuation of treatment.

Alpha Blockers
Clonidine (Catapres), prasozin (Hypovase), doxazosin (Cardura), terazosin (Hytrin). Function: chemically block responses to stress that raise blood pressure and heart rate. Side effects: dry mouth, dizziness, fatigue, nausea, impaired sexual functioning; as with beta blockers, sudden discontinuation of treatment can result in dramatic increases in blood pressure.

Diuretics
Bendrofluazide (Aprinox, Berkozide, Neo-Bendromax, Neo-NaClex), bumetanide (Burinex), cyclopenthiazide (Navidrex), frusemide (Lasix), hydrochlorothiazide (HydroSaluric), indapamide (Natrilix), metolazone (Metenix 5) and mefruside (Baycaron). Function: stimulate the kidneys to excrete more salt and water, lowering blood volume and blood pressure. Side effects: dangerously low levels of potassium and magnesium, elevations in uric acid (which can cause gout attacks), increases in blood cholesterol.

Calcium-Channel Blockers
Amlodipine besylate (Istin), diltiazem (Tildiem, others), verapamil (Cordilox, Securon, others), nifedipine (Adalet, Angiopine, others). Function: relax blood vessel walls to make them dilate, thus lowering blood pressure. Side effects: constipation, dizziness, nausea, fluid retention.

ACE (Angiotensin-Converting Enzyme) Inhibitors
Enalapril maleate (Innovace), captopril (Capoten), quinapril (Accupro),
lisinopril (Carace, Zestril), others. Function: block an enzyme in the bloodstream that produces angiotensin 11, a chemical that raises blood pressure by constricting blood vessels. Side effects: long-term cough, acute swelling in the face, lips and throat.

Angiotensin II Blockers
Candesartan cilexetil (Amias), irbesartan (Aprovel), losartan potassium(Cozaar), valasartan (Diovan). Function: block the effect of angiotensin rather than its production. Side effects: rare.

324 • EXPLORING YOUR TREATMENT OPTIONS
EIGHT WAYS TO FIGHT HIGH BLOOD PRESSURE
Here are eight more tips for lowering high blood pressure and reducing or preventing a dependence on blood pressure drugs.
· Eat fewer calories. Lowering your body weight if it's too high is one key way to lower your blood pressure.
· Avoid refined carbohydrates such as white flour and sugar, white potatoes (especially chips) and sugar-sweetened soft drinks. All of these supply `empty' calories, meaning they're unusually bereft of nutrients and they lead to weight gain. They also fill you up so that you have no room left for healthful foods.
· Don't drink more than 1/ litre of beer, or 120 millilitres of wine, or 30 milli­litres of spirits per day. Higher amounts of alcohol are known blood pressure boosters.
· Eat high-fibre foods such as flaxseed meal and other whole grains and vegetables. In addition to boosting dietary fibre, these foods contain nutrients that lower blood pressure. And fibre makes you feel full, which helps you lose weight if you need to.
· Eat deep-sea fish that are rich in essential fatty acids, such as salmon, cod, mackerel and tuna. The omega-3 fatty acids in fish tend to relax artery walls, reducing blood pressure. They also make blood thinner and less likely to clot.
· Emphasise foods high in magnesium, potassium and calcium. On the list: nuts and seeds, green leafy vegetables, legumes, whole grains, tofu, bananas, oranges, apples, avocados and melons.
· Stop smoking. Cigarette smoking raises your blood pressure by constricting arteries. It also damages heart muscle and other tissues by decreasing the amount of oxygen they get.
· Engage in regular aerobic exercise for 30 or 40 minutes three or four times a week. Such exercise has been shown to lower blood pressure and prevent heart attacks.

HERBAL REMEDIES

Hawthorn (Crataegus spp.)
The leaves, flowers and berries of this tree have a well-deserved reputation as general tonics for the cardiovascular system. Hawthorn is perhaps the best-known botanical medicine used in the treatment of mild high blood pressure. A hawthorn extract is commonly used by herbalists for improving heart function and treating congestive heart failure, irregular heartbeats and angina. It is a rich source of oligomeric proanthocyanidins (OPCs) and antioxidant bioflavo­noids, both of which nourish the tissues of the heart and the blood vessels.

Hawthorn lowers blood pressure by relaxing and dilating artery walls. How the herb does this is only partly understood. It appears to possess similarities to ACE inhibitors, beta blockers and calcium­channel blockers. Since hawthorn can take weeks or even months to work, it should not be used by itself for significantly high blood pressure (above 160 over 100). But it is the ideal herb to use in the early stages of high blood pressure. Typical dosage: 150 to 1,500 milligrams of powdered standardised extract (one that contains 10 to 18 per cent OPCs or 1.8 per cent vitexin-4'-rhamnoside).


Reishi (Ganodenna lucidum)
This mushroom is prized in Japan and China, where its rejuvenating qualities have been known for over 4,000 years. Scientific studies have confirmed its medicinal properties. Published studies show that in humans it lowers blood pressure and reduces 'bad' LDL cholesterol and triglycerides, another type of blood fat. It also reduces the tendency of blood platelets to accumulate, thus making blood less likely to clot and provoke heart attacks and strokes. Since the raw mushroom is woody and inedible, the traditional method of preparing reishi is to make a tea by simmering it for a long time in water. Fortunately, it is also available in a powdered form. Typical dosage: 1,000 to 9,000 milligrams in capsules per day; or 50 to 75 milligrams in concentrated capsules three times per day.

Garlic (Allium sativum)
This common seasoning has been used as a medicine in many cultures for more than 3,000 years. It is known to lower blood pressure and cholesterol, treat infections and prevent cancer. The sure-fire way to lower blood pressure with garlic is to eat one to three raw or lightly cooked garlic cloves every day. If you can't handle the garlic breath that results, or you suffer from heartburn or an easily irritated stomach, garlic is available in other forms. Typical dosage: 1 to 3 standardised tablets (guaranteed to provide at least 4,000 micrograms of allicin each) per day.

Coleus (Coleus forskohlii)
An extract of this herb (not to be confused with the houseplant of the same name), forskolin, is used extensively in India to treat numerous conditions, including high blood pressure and asthma. Forskolin has been shown to increase the concentration of a chemical called cAMP, found in smooth muscles. Increased levels of cAMP relax those smooth muscles, thus dilating the walls of arteries. Forskolin also appears to help heart muscle work more efficiently. Since the root contains only small amounts of the active ingredient, it is important to use a concentrated extract. Typical dosage: 50 milligrams three or four times per day.

Dandelion (Taraxacum officinale)
The leaves of your favourite lawn weed are a popular home remedy for fluid retention. By gently increasing urine flow, dandelion leaf helps to lower blood pressure as well. In very high doses the herb can have a diuretic effect. The advantages of using dandelion are twofold: it does not appear to cause potassium loss - a significant problem with some prescription diuretics - and, at the right time of year, almost anyone can find fresh dandelion greens to throw into a salad or make into a juice or tea. (Avoid leaves that have been treated with chemicals.) Typical dosage: 2 to 6 cups of tea per day (simmer I to 2 teaspoons of dried leaves in 1/4 litre of water for 5 minutes); or 1 to 2 dropperfuls of tincture up to three times per day; or one 500-milligram capsule three or four times per day.

MINERAL `MAGIC'
One of the deadliest consequences of high blood pressure is stroke, but it is also the one with a proven dietary therapy. The DASH (Dietary Approaches to Stop Hypertension) study, performed at four medical centres in America, showed that people who ate foods rich in potassium, magnesium and fibre had a lower incidence of stroke.