Weight reduction Salt restriction Limiting alcohol Exercise Quit smoking Eat healthily Rest and relaxBy DR AIZAI AZAN RAHIM
HYPERTENSION or high blood pressure is a major risk factor in cardiovascular disease (CVD) and a common cause of morbidity and mortality in the general population. The primary goal of treatment is to lower the blood pressure to the recommended levels by whatever means possible.
Medication has always been the mainstay of therapy, but many hypertensives wonder if there is anything else they can do to reduce their blood pressure. The good news is that there are several lifestyle changes a person can adopt which can make a difference.
A healthy lifestyle is imperative for anyone and are especially critical for people with high-normal blood pressure (130-139/85-89mmHg) and mild (stage 1) hypertension (140-159/90-99mmHg). In fact, it may be the only treatment necessary in the absence of other risk factors for heart disease. However, in diabetics, pharmacological treatment should be initiated when the blood pressure is persistently greater than 130/85mmHg.
In the Treatment of Mild Hypertension Study (TOMHS), intensive lifestyle intervention resulted in an 8- to 9mmHg reduction in both systolic and diastolic blood pressures. It also led to a reduction in the requirement for additional drugs in patients already receiving one drug. Therefore, it should remain the cornerstone of therapy for all hypertensives on drug therapy.
Lifestyle changes also contribute to improved overall cardiovascular health and will reduce the risk of heart attacks, strokes and kidney failure. Furthermore, recent data suggests that lifestyle modifications have a great part to play even in the prevention of hypertension.
Obesity (especially abdominal obesity) has been associated with an increased risk of high blood pressure. In the Trial of Hypertension Prevention (TOHP) and the Trial of Non-Pharmacologic Interventions in the Elderly (TONE), an 8- to 10lb reduction in weight produced a modest 3- to 4mmHg reduction in blood pressure. On average, every 1kg of body weight lost will result in a fall of blood pressure by 2mmHg. Weight-loss, particularly accompanied by salt restriction, may allow for the safe reduction of medication in patients with mild hypertension.
To this end, a change in dietary habits, to healthier foods, and a slow reduction in weight, through an increase in physical activity and a modest reduction in calorie intake, is more likely to be successful than any rapid and radical changes, which would be difficult to maintain in the long-run.
About half of hypertensives have blood pressure that reacts significantly to salt. Salt contains sodium, which encourages fluid retention, which in turn elevates blood pressure. Such people are thought to be salt-sensitive and include the elderly, diabetics, African-Americans, overweight people and those with kidney problems.
Reducing salt intake also enhances the effects of nearly all standard antihypertensive drugs. On average, a reduction of 6mmHg in systolic and 2mmHg in diastolic pressure is achievable with moderate sodium restriction.
An intake of less than 100mmol of sodium or 6g of sodium chloride a day (equivalent to 1¼ teaspoonful of salt) is recommended. Simply eliminating salted fish, salted eggs and cooking salt is beneficial, but do remember that most of the salt in our diet comes from commercial food such as soy sauce, oyster sauce and canned tomato juice or soup.
Excessive alcohol intake has an acute effect in elevating blood pressure. In the Multiple Risk Factor Intervention Trial (MRFIT), increased alcohol intake was associated with increased blood pressure and the development of resistant hypertension. Experts recommend moderation. Limit intake to no more than two drinks a day for men and one drink a day for women (one drink is equivalent to 12oz of beer or 5oz of wine or 1oz of whisky). The reason why the limit is lower in women is because women absorb alcohol more easily than men. A reduction in alcohol consumption can also assist with weight reduction as it is high in calories. Those who are unable to reduce their drinking on their own should consult their doctor for help.
Several recent studies have suggested that regular aerobic exercise does not only reduce the risk of developing hypertension, but can also lower resting blood pressure in hypertensives by about 10 mmHg systolic and 8mmHg diastolic.
This level of reduction in pressure is equivalent to that achievable by weight reduction. Aerobic exercise is more effective than resistance training (e.g. weight-lifting ) and even light to moderate intensity aerobic exercise such as walking for 3060 minutes at least three times a week is highly recommended.
Exercise is especially important for those who are overweight, to facilitate weight-loss and improve cholesterol levels. It is also an excellent way of relieving tension. Some smaller studies have indicated that practising yoga and qi gong may also help lower blood pressure.
It is important that you choose activities that you enjoy. Even if you are unable to exercise regularly, you should attempt to be more active. For example, wash your car instead of using a carwash, and use the stairs instead of the lift. Regular exercise helps keep arteries elastic and reduces sympathetic nervous system activity, which in turn ensures good blood flow and normal blood pressure. However, high-intensity workouts should be avoided by high-risk individuals as they tend to over stress the heart and may cause spasms in the arteries leading to it. Those with heart disease or other significant medical conditions should consult their doctor before changing their level of physical activity.
Cigarette smoke contains at least 4000 chemicals that are hazardous to ones health. Smoking puts an extra burden on the cardiovascular system as nicotine constricts blood vessels, which increases blood pressure, whilst carbon monoxide decreases the blood oxygen content. Smoking also promotes atherosclerosis (the progressive hardening and narrowing of arteries), which may lead to chest pain and, eventually, heart attacks and other complications.
For instance, if the blood supply to the brain is compromised, the result will be a stroke, leading to paralysis or death. If the arteries in the legs become narrowed, this can result in peripheral vascular disease (signs include pain in the calf when walking), leg ulcers and even gangrene.
Non-smokers are also at risk through passive smoking. Studies have shown that those living with smokers have about a 25% increased risk of developing heart disease.
Research has found that diet also plays a part in the development of hypertension. A recent study has shown that a diet rich in vegetables, fresh fruits, and low-fat dairy products lowers blood pressure. Hypertensive patients on this diet, called Dietary Approaches to Stop Hypertension (DASH ), experienced an average reduction in blood pressure of 11mmHg systolic and 5mmHg diastolic below that seen with the traditional American diet. The diet makes the following recommendations:
·Avoid saturated fats. Select low-fat or non-fat dairy foods.
·When choosing fats, select monounsaturated oils such as olive or canola oils and polyunsaturated ones.
·Have seven to eight servings of whole grains and grain products daily. These include whole wheat bread, cereals, rice, oatmeal or pasta products which are major sources of energy and fibre.
·Have four to five servings of fresh fruit and vegetables daily. These are important sources of fibre, potassium and magnesium.
·Have one to two servings of protein (preferably fish, poultry, tofu or lean meat) per day. Include four to five servings of nuts (almonds, walnuts, peanuts), seeds and legumes (beans or peas), all rich sources of energy, protein, potassium and fibre, per week.
Studies have indicated that potassium deficiency increases the risk of developing hypertension and many now believe that potassium-rich food can help to lower blood pressure. Excess potassium, however, can cause abdominal distress and irregular heart beats, and should be avoided in people with kidney problems.
Calcium supplements have also been reported to lower blood pressure. However, in this case, the blood pressure reduction is minimal. Therefore, while hypertensives are advised to maintain an adequate intake of potassium, calcium supplements are not routinely recommended at this time and the same goes for magnesium, micronutrients and fibre supplementation.
Rest and relax
Improving ones mood or relieving stress through stress-reduction programmes may help lower blood pressure by reducing sympathetic nervous system activity. However, it does not prevent the development of hypertension.
Insufficient sleep may raise blood pressure in patients with hypertension and, according to a small Italian study conducted in 1999, blood pressure and heart rate were higher the morning after a sleep-deprived night compared with the morning after a full night of sleep. There is, however, no evidence that sedatives or tranquilisers lower blood pressure in the medium to long term. Patients with chronic insomnia, or other conditions involving severe sleep disturbance, should consider consulting psychologists or sleep experts for help.
Changing ones lifetstyle in the manner discussed above will definitely reduce blood pressure for most hypertensives. Those with mild hypertension may even be able to avoid being put on medication, whilst for those with moderate or severe hypertension, a reduction in their drug dosage may be possible. Lifestyle modifications should, therefore, be promoted.
The Malaysian Hypertension Club (MHC) will be launched on Saturday, Oct 11 at Prince Hotel, Kuala Lumpur. A free health screening and public forum will be held at 4pm during this launch. Members of the public are welcome to attend this event. For more information, call tel: 03-79550707 or 03-79662773.
n Dr Aizai Azan Rahim is a consultant cardiologist and clinical director of the Cardiac Rehabilitation Unit, National Heart Institute, Kuala Lumpur, and a council member of the Malaysian Society of Hypertension.
Did you find this article insightful?