Which lifestyle changes should I suggest?

While there is no direct randomised evidence demonstrating that reducing blood pressure through lifestyle measures reduces the risk of cardiovascular disease, this seems likely given all the other evidence suggesting that the benefits of antihypertensive treatment are determined primarily by the blood pressure reduction per se rather than by any other independent effect of particular treatment modalities.

Lifestyle measures (or non-pharmacological treatments) are used for a number of complementary reasons as outlined in the WHO Technical Report on Hypertension Control:

• to lower the blood pressure in the individual patient.
• to reduce the need for antihypertensive drugs and maximise their efficacy.
• to address the other risk factors present.
• for primary prevention of hypertension and associated cardiovascular disorders in populations.

Smoking cessation
Smoking cessation is perhaps the single most powerful lifestyle measure for the prevention of both cardiovascular and non-cardiovascular diseases in hypertensive patients. All hypertensive patients who smoke should receive appropriate counselling for smoking cessation. Nicotine replacement therapy should also be considered, since it appears to augment other interventions for smoking cessation.

Weight reduction
Excess body fat contributes to blood pressure levels from infancy and is the most important factor predisposing to hypertension. Weight reduction of as little as 5 kg reduces blood pressure in a large proportion of hypertensive individuals who are more than 10% overweight and also has a beneficial effect on associated risk factors such as insulin resistance, diabetes, hyperlipidaemia and left ventricular hypertrophy. The blood pressure lowering effects of weight reduction may be enhanced by simultaneous increase in physical exercise, by alcohol moderation in overweight drinkers, and by reduction of sodium intake in older hypertensive subjects (TONE Study). Weight loss of at least 5 kg should be recommended in the first instance, with further increments of 5 kg depending upon the response and the patients' weight.

Moderation of alcohol consumption
Notwithstanding the evidence that an alcohol intake of up to 3 "standard" drinks a day may lower the risk of CHD, there is a linear relationship between alcohol consumption, blood pressure levels, and the prevalence of hypertension in populations. Alcohol attenuates the effects of antihypertensive drug therapy but its pressor effect is, at least partially, reversible within 1-2 weeks by moderation of drinking by around 80%.132 Heavier drinkers (5 or more standard drinks a day) may experience a rise in blood pressure after acute alcohol withdrawal and be more likely to be diagnosed as hypertensive at the beginning of the week if they have a weekend drinking pattern. Accordingly, hypertensive patients who drink alcohol should be advised to limit their consumption to no more than 20-30 g of ethanol per day for men, and no more than 10-20 g of ethanol per day for women. They should be warned against the heightened risks of stroke associated with binge drinking.

Reduction in salt intake
Epidemiologic studies suggest that dietary salt intake is a contributor to blood pressure elevation and to the prevalence of hypertension. The effect appears to be enhanced by a low dietary intake of potassium containing foods. Randomised controlled trials in hypertensive patients indicate that reducing sodium intake by 80-100 mmol (4.7-5.8 g) per day from an initial intake of around 180 mmol (10.5 g) per day will reduce blood pressure by an average of around 4-6 mmHg SBP. However, individuals vary considerably in their responses to changes in dietary salt, with black, obese and elderly subjects the most sensitive. A recent study in older hypertensive patients showed no adverse effects of a reduction in sodium of 40 mmol (2.3 g) per day and after 18 months there was a significant reduction in the need for antihypertensive drug therapy. The aim of dietary sodium reduction should be to achieve an intake of less than 100 mmol (5.8 g) per day of sodium or less than 6 gm per day of sodium chloride. Patients should be advised to avoid added salt, to avoid obviously salted foods, particularly processed foods, and to eat more meals cooked directly from natural ingredients. Counselling by trained dieticians and monitoring of urinary sodium are necessary in most cases. The high sodium – low potassium content of many preserved foods is drawn to the attention of the food industry.

Complex dietary changes
Vegetarians have lower blood pressure than meat eaters and vegetarian dietary patterns can lower blood pressure in hypertensive patients. A series of controlled dietary trials indicate that these effects depend on a combination of effects of fruit, vegetables, fibre and low saturated fat intake rather than the presence or absence of meat protein. This conclusion has been confirmed in a recent study in which older subjects with mild or borderline hypertension were randomised for eight week periods to continue their normal diet, to increase fruit and vegetable consumption alone, or to also reduce their consumption of total and saturated fat. Increasing fruit and vegetable consumption alone caused SBP/ABP to fall by 3/1 mmHg while the added measure of reducing fat intake led to a fall of 6/3 mmHg. In the patients with higher initial blood pressures, there was a fall of 11/6 mmHg with the combined dietary regime. The presence of higher intakes of calcium, magnesium or potassium may have contributed to the beneficial effects of some of these diets. Regular fish consumption as part of a weight reducing diet may enhance blood pressure reduction in obese hypertensive patients and yield additional benefits on lipid profiles. Hypertensive patients should be advised to eat more fruit and vegetables, to eat more fish and to reduce their fat intake.

Increased physical activity
Sedentary patients should be advised to take up modest levels of aerobic exercise on a regular basis, such as a brisk walk or a swim for 30-45 minutes, 3-4 times a week. Such mild exercise may be more effective in lowering the blood pressure than more strenuous forms of exercise such as running or jogging, and may lower the systolic pressure by about 4-8 mmHg. Isometric exercise (e.g. heavy weight lifting) can have a pressor effect and should be avoided.

Psychological factors and stress
Psychological factors, personality factors and stress are associated with the adoption of many less healthy lifestyle patterns associated with hypertension and increased risk of cardiovascular disease. In this sense, helping individuals to cope with stress may have an important impact on their blood pressure and on compliance with antihypertensive medications. Whether there are more direct effects of sustained stress on long-term blood pressure levels is a subject requiring ongoing research. To date, trials of various stress management procedures for blood pressure control have been unconvincing.

Other measures
Lifestyle measures are fundamental for the management of diabetes and the treatment of hyperlipidaemia, and appropriate measures should be instituted when these disorders are present in the hypertensive patient. These will generally include a diet low in saturated fat and rich in vegetables and fruit.

Interventions with limited or unproven efficacy in lowering blood pressure include bio-feedback, micronutrient alterations and dietary supplementation with calcium, magnesium, and fibre.