Although precise targets in different population groups (or different people with different comorbidities) are debatable, what we do know is that everyone should at least be treated with a theoretical target blood pressure of less than 140/90mmHg.

We might consider targets lower than that if the patient is at a high cardiovascular risk but only if these lower blood pressures are deemed safe on clinical grounds. For example, we wouldn’t take an aggressive approach to the reduction of blood pressure in a frail female of advanced age who is prone to falls. We’ll also only consider lower targets if drug therapy is well tolerated. That is if the patient does not experience any adverse effects associated with the antihypertensives used to reach that lower target (like hypotension, syncope/fainting, electrolyte abnormalities, or acute kidney injury).

In practice, we sometimes struggle to get some patients’ BP down even to 140/90, despite combining several different antihypertensive treatment options. In these cases, we can be reassured that even if we don’t reach our target of 140/90, just moving the BP down towards it will help to improve the patient’s outcomes.

Clinical Tip:

• For patients who require BP-lowering therapy, aim to reduce BP below 140/90 mmHg
• In patients with high atherosclerotic CV disease risk, lowering BP to below 130/80 mmHg reduces cardiovascular morbidity and may reduce mortality.

Remember the ‘SNAP’ risk factors. The non-pharmacological therapy aims to target the SNAP risk factors for disease.

• Smoking cessation – has been shown to reduce blood pressure and overall CVD risk.  The risk of smoking on CVD risk declines dramatically over the next 2-6 years to a level comparable to a non-smoker.

Weight control can assist with blood pressure management.  A number of studies have associated weight loss with systolic and diastolic blood pressure reduction.  A weight reduction of 1 kilogram was associated with lowering systolic and diastolic blood pressure by an average of 1 mmHg.  Weight reduction can be achieved through Nutrition modification, reduction or elimination of alcohol and increased physical activity

• Nutrition/diet – there is a relationship between sodium intake and blood pressure.  Sodium restriction is shown to lower systolic and diastolic blood pressure, particularly in patients with hypertension.  Low sodium intake diets are associated with reductions in blood pressure.  The National Heart Foundation Guidelines recommend limiting salt intake to ≤ 6g/day for primary prevention and 4g/day for secondary prevention.  Consumption of a diet that emphasises intake of vegetables, fruits and whole grains, low fat dairy, combined with exercise and weight loss can reduce blood pressure too.
• Alcohol – the consumption of 2 or more standard drinks a day for healthy men and women can immediately increase blood pressure.   Consumption of ≥ 2 standard alcoholic drinks for men and ≥ 1 standard alcoholic drinks for women per day increases the risk of developing hypertension.
• Physical activity – there is strong evidence that regular physical exercise and moderate to high levels of cardiorespiratory fitness protect against hypertension.  Australian guidelines for patients with hypertension advocate for 30-60 minutes of moderate-intensity activity or 15-30 minutes of vigorous intensity activity 5 days a week, every week plus muscle strengthening activities on at least 2 days each week.  For adults > 65 years, aim for 30 minutes of moderate-intensity physical activity on most or all days.

First-line drug classes have similar efficacy in reducing blood pressure.  Usually, treatment is started with a low-to-moderate dose of the first chosen antihypertensive. That will be continued for approximately 3 months, and if the target BP is not reached in that time, then a low-moderate dose of a second drug from a different class will be added. This will help to maximise antihypertensive effect while minimising adverse effects associated with a single agent.

The initial drug choice should be a patient-centred decision, that includes consideration of the patient’s comorbidities, any potential for interactions with other drugs the patient is taking, the recommended dosing frequency (as once daily dosing may lead to better adherence than multiple daily dosing), cost, and patient preference too.  Combining antihypertensives is indicated if the target BP is not reached 3 months after starting the initial anti-hypertensive.

What are the drug agents for lowering blood pressure?

We already discussed the pharmacology of CCB’s in relation to stable angina, but read on to learn more about ACEI, A2RBs and diuretics.