High blood pressure | Mate pēhanga toto

Also known as hypertension

High blood pressure (mate pēhanga toto) is a common condition in which the force of your blood against your artery walls is too high, too often. Ongoing high blood pressure puts stress on your heart and can lead to health problems, such as heart disease and stroke. High blood pressure is also known as hypertension.

On this page, you can find the following information:

What is high blood pressure?
Why is high blood pressure a problem?
What causes high blood pressure?
Who needs to get their blood pressure checked?
How is high blood pressure diagnosed?
How is high blood pressure treated?
How can I prevent high blood pressure?

Key points

At least 1 in 5 New Zealanders has high blood pressure, but most don't know they have it.
High blood pressure usually doesn't have symptoms, so the best way to find out if you have high blood pressure is to get your blood pressure checked regularly. Your doctor, nurse or pharmacist can do this for you.
Untreated high blood pressure can cause serious problems such as stroke, heart attack and kidney failure.
You can manage high blood pressure through healthy lifestyle choices and medications if needed.
If you need medicine for blood pressure, take it every day as prescribed. If you have any questions, ask your doctor or pharmacist.

What is high blood pressure?

Blood pressure (pēhanga toto) is the force of your blood pushing against the walls of your arteries. Read more about blood pressure.

Blood pressure is measured in millimetres of mercury (which is written as mmHg). Blood pressure readings are a combination of two measurements:

Systolic – the highest pressure against your arteries as your heart pumps. The normal systolic pressure is usually between 110–130 mmHg.
Diastolic – the pressure against your arteries as your heart relaxes and fills with blood. The normal diastolic pressure is usually between 70–80 mmHg.

High blood pressure may be considered to be 140/90 mmHg or higher. However, it is difficult to give an example of a high blood pressure reading, because it depends on the individual. The level of blood pressure that is high for you depends on lots of different factors and your overall risk of heart attack or stroke. Generally, the lower your blood pressure, the better. If you have a history of heart disease, diabetes or a high risk of heart attack or stroke, it's recommended you lower your blood pressure to less than 130/80. See who needs to get their blood pressure checked?

A single high blood pressure reading does not necessarily mean that you have high blood pressure. It's normal for your blood pressure to rise and fall during the day, depending on what you have been doing (eg, exercise) and how you are feeling (eg, stressed).

You are usually considered to have high blood pressure if your blood pressure stays high for 3 separate readings, over at least 3 months. For some people, doing measurements at home with a machine can be more accurate than doing it in the clinic with your doctor or nurse.

To find out if you need to do something about your blood pressure levels, visit your doctor and have a heart and diabetes check. In your heart and diabetes check, your doctor, nurse or other health professional will discuss your ideal blood pressure, taking into account your overall risk of having a heart attack or stroke.

Why is high blood pressure a problem?

Over time, high blood pressure damages your blood vessels. It can lead to the following complications.

Complications of having high blood pressure	Description
Heart attack	High blood pressure damages arteries that can become blocked and prevent blood flow to the heart muscle.
Angina	High blood pressure can lead to heart disease or microvascular disease, of which angina, or chest pain, is a common symptom.
Stroke	High blood pressure can cause blood vessels in your brain to clog more easily or even burst.
Heart failure	The increased workload from high blood pressure can cause your heart to enlarge and fail to supply blood to your body.
Kidney disease or kidney failure	High blood pressure can damage the arteries around your kidneys and interfere with their ability to filter blood effectively.
Eyesight problems	High blood pressure can strain or damage blood vessels in your eyes and can lead to loss of vision.
Peripheral artery disease	Atherosclerosis caused by high blood pressure can cause a narrowing of arteries in your legs, arms, stomach and head, causing pain or fatigue.
Sexual problems	High blood pressure can lead to erectile dysfunction in men or lower libido in women.

Image credit: 123RF

What causes high blood pressure?

High blood pressure often runs in families. Sometimes kidney or glandular disease may be responsible. However, eating too much salt, drinking too much alcohol, being overweight and not moving around enough each day can also contribute to high blood pressure and heart disease.

The effects of high blood pressure on your blood vessels are worsened by:

cigarette smoking
high levels of saturated fat in your diet
high blood cholesterol.

Some medicines may cause raised blood pressure or make controlling it more difficult. These medicines include:

the combined contraceptive pill
non-steroidal anti-inflammatories (NSAIDs)
some nasal drops and sprays
some cough medicines, eye drops and appetite suppressants.

Check with your doctor or pharmacist for alternatives.

Who needs to get their blood pressure checked?

Every adult should have your blood pressure checked regularly. The age you are advised to start having heart and diabetes checks depends on your age, ethnicity and other risk factors.

Risk factors	Age to start having heart and diabetes checks
If you have no known risk factors	Men: 45 years Women: 55 years
If you are Māori, Pasifika or South Asian¹	Men: 30 years Women: 40 years
If you have the following risk factors: you smoke you have a family history of diabetes, high cholesterol, heart attack or stroke² you have gestational diabetes (diabetes during pregnancy) or prediabetes you are overweight³ you have kidney disease you have high blood pressure or cholesterol you have previously had a heart trouble or stroke you have a heart condition such as atrial fibrillation.	Men: 35 years Women: 45 years
If you have diabetes (type 1 or 2)	As part of your yearly diabetes review
If you have schizophrenia, major depressive disorder, bipolar disorder or other severe mental illness	25 years
South-Asian peoples: Indian, including Fijian Indian, Sri Lankan, Afghan people, Bangladeshi, Nepalese, Pakistani, Tibetan Family history: Parent, brother or sister Overweight: BMI ≥ 30 or weight around your tummy (waist circumference ≥ 102 cm in men or ≥ 88 cm in women)

Read more about heart risk assessment.

How is high blood pressure diagnosed?

High blood pressure does not usually have any symptoms, so the only way to find out if you have it is to get your blood pressure checked by your doctor, nurse or pharmacist. They will often take several readings over weeks or months to see what the trend is.

Your doctor may suggest 24-hour blood pressure monitoring. This involves wearing a blood pressure unit for up to 24 hours to collect a series of blood pressure and heart-rate readings at different times of the day and night. Read more about 24-hour blood pressure monitoring Heart Foundation, NZ

How is high blood pressure treated?

Your doctor will work out your five-year risk of cardiovascular disease (eg, heart attack or stroke) to work out the likely benefits of blood pressure-lowering interventions.

If you have low risk, following the self-care steps listed below, such as stopping smoking, eating a balanced diet, less salt, less alcohol and becoming more physically active, may be enough. If your risk is higher, you are likely to need medication as well as following the self-care steps.

Self-care for high blood pressure

Stop smoking – quitting is the most important step to reduce your risk of heart attack and stroke.
Achieve and maintain a healthy body weight. The more overweight you are, the more strain you put on your heart and cardiovascular system. For some people, losing 5–10kg of excess weight is enough to get your blood pressure back to normal. Check with your doctor, nurse or pharmacist as to what is right for you.
Eat a balanced diet low in saturated fat with whole grains, 8 servings of coloured vegetables and fruit, and 2 to 3 servings of low-fat milk or milk products a day. Learn more about the DASH eating plan to lower high blood pressure.
Eat less salt – use herbs, spices, citrus and vinegar for flavouring and dressings, choose low-salt versions of packaged foods, avoid pickled food and salty or fatty takeaway foods. Read more about reducing salt intake
Limit alcohol consumption and follow recommended guidelines for low-risk drinking.
Be active every day. Find ways to put a little bit more activity in your day at every opportunity. Take the stairs at work. Park 5 minutes further away. Aim to get 30 to 60 minutes of moderate activity most days of the week. Walking, cycling and swimming are ideal. Find an activity you enjoy so you can keep it up. Find out more about getting active.
Avoid eating large quantities of liquorice – it contains a chemical that can raise blood pressure.

See also these tips for lowering blood pressure.

Medicines for high blood pressure

Medications can help control high blood pressure and reduce the damage from high blood pressure, but they do not cure it. Usually, medication will need to be taken for life, unless losing weight and the lifestyle changes are so successful that your blood pressure returns to normal levels without medication.

There a variety of medicines that can be used to lower blood pressure. Each of these groups of medicines works differently. Sometimes 2 or 3 medications are needed and it may take time to find the right combination and dosage. Tell your doctor or pharmacist about any side effects you may have and follow instructions carefully.

Examples of medicines to treat blood pressure include:

ACE inhibitors such as cilazapril, lisinopril, quinapril, enalapril, perindopril.
ARBs such as candesartan, losartan.
Beta blockers such as bisoprolol, metoprolol, propranolol.
Calcium channel blockers such as amlodipine, diltiazem, felodipine.
Diuretics (also called water pills) such as bendroflumethiazide, chlortalidone, indapamide.

Read more about medicines to treat blood pressure.

Because high blood pressure puts you at increased risk of cardiovascular disease, you may also be prescribed other medicines to help reduce your risk of heart disease and stroke, such as:

aspirin
medications to lower cholesterol (statins).

How can I prevent high blood pressure?

With a little effort, there is much you can do to reduce your risk of getting high blood pressure and the increased risk of stroke and heart disease that goes with that. Key steps are to:

keep to a healthy body weight
be active regularly
eat a balanced diet
eat less salt
limit how much alcohol you drink
quit smoking
reduce stress
avoid eating large quantities of liquorice.

Read more about how to prevent high blood pressure.

Support

The Stroke Foundation has developed He taonga, a tool to help you and your whanau maintain a healthy blood pressure and improve your hauora. He taonga is a 6-week online programme designed to provide you with the support and motivation to make lifestyle changes. The programme is delivered through weekly emails that contain advice, support and links to videos and resources.

Check out the free He taonga programme.

Learn more

DASH Eating plan to lower high blood pressure
High blood pressure personal stories Health Talk online
High blood pressure Heart Foundation NZ
High blood pressure NHS, UK
Family health history Learn Genetics (Genetic Science Learning Centre), University of Utah, US, 2015
High blood pressure and the cardiovascular system Watch, Learn, Live – Interactive Cardiovascular Library, American Heart Association

References

Managing high blood pressure Heart Foundation, NZ
Health threats from high blood pressure American Heart Association, 2016
Blood pressure (high) – hypertension Better Health Channel, Australia, 2011
What's my risk of a heart attack or stroke? Heart Foundation, NZ
Blood pressure and hypertension in New Zealand – results from the 2008/09 Adult Nutrition Survey NZ Med J. 2013 April 5;126(1372).
NZ health survey 2018/19 Ministry of Health, NZ, 2019

Reviewed by

Dr Hari Talreja is a renal physician/hypertension specialist with advanced training from Canada and a master’s degree from Harvard University in the USA. He is one of the very few American Society of Hypertension-certified hypertension specialists in New Zealand. He is the clinical lead for transplantation, hypertension and clinical research at Counties Manukau Health. He also practises at Ormiston Specialists Centre, Flatbush and Gilgit Road Specialist Centre, Epsom.

Credits: Health Navigator Editorial Team . Reviewed By: Dr Hari Talreja, Specialist Renal and Hypertension Services, Auckland Last reviewed: 08 Jan 2020 Page last updated: 10 Jul 2022

How can high blood pressure be prevented?

High blood pressure is one of the most common health problems as people get older. With a little effort, there is much you can do to reduce your risk of getting high blood pressure and the increased risk of stroke and heart disease that goes with that.

Keep to a healthy body weight

One of the key risk factors for high blood pressure is being overweight. Being overweight can make you 2 to 6 times more likely to develop high blood pressure than if you are in the normal weight range. Even small amounts of weight loss can make a big difference in helping to prevent and treat high blood pressure.

Be active regularly

People who are physically active have a lower risk of getting high blood pressure (20–50% lower) than people who are not active. Even light activities, if done daily, can help lower your risk. Add more activity to your day. Aim to get 30 to 60 minutes of physical activity most days of the week. Walking, cycling and swimming are ideal. Find an activity you enjoy so you can keep it up.

Look for opportunities to add a few minutes here and there – it all helps. Take the stairs whenever you can, park 5 minutes further from work, go for a walk at lunchtime or when you get home. Read more about getting active.

Eat a balanced diet

Your diet – what you eat and drink – has a real effect on your heart and blood pressure. The more healthy your eating habits are, the lower your blood pressure will be. A heart healthy diet is low in saturated fat, whole grains, 8 servings of coloured vegetables and fruit, and 2 to 3 servings of low-fat milk or milk products a day. Read more about healthy eating.

Eat less salt

Cutting back on salt also helps prevent your blood pressure from rising. Reduce your sodium intake to 2300mg of sodium a day (about 6g salt) or less. This includes sodium from processed food. Use herbs, spices, fruit and vinegar for flavouring and dressings. If you have pre-prepared foods, avoid pickled food and avoid salty or fatty takeaway foods. Read more about reducing your salt intake.

Limit how much alcohol you drink

Drinking too much alcohol can raise your blood pressure. Limit how much alcohol you drink and follow recommended guidelines for low-risk drinking.

Quit smoking

Being smokefree is one of the best things you can do to lower your risk of heart attack and stroke. While smoking does not directly affect your blood pressure, it will cause your arteries to narrow just as high blood pressure does. This puts you at much higher risk of heart disease and stroke.

So, if you smoke and have high blood pressure, your arteries will narrow much more quickly and your risk of a heart attack or stroke in the future is dramatically increased. Because of this, as well as for all the other effects it has on your health, it well worth giving up smoking. Read more about quitting smoking.

Reduce stress

Stress can make blood pressure go up, and over time may contribute to the cause of high blood pressure. There are many steps you can take to reduce your stress. Read more about managing stress.

Avoid eating large quantities of liquorice

Liquorice contains a chemical that can raise blood pressure. Eating more than 57g of black liquorice a day for at least 2 weeks could lead to potentially serious health problems, such as an increase in blood pressure and an irregular heart rhythm (arrhythmia).

For most people, liquorice found in foods is safe to eat and safe when consumed in small amounts for short periods of time.

References

High blood pressure prevention WebMD, US, 2019
Sodium position statement Heart Foundation, NZ
Smoking and your blood pressure Blood Pressure UK
Can eating too much black liquorice be bad for you? NHS, UK, 2018

Information for healthcare providers on high blood pressure

The content on this page will be of most use to clinicians, such as nurses, doctors, pharmacists, specialists and other healthcare providers.

The page contains the following sections:

Clinical guidelines
Regional HealthPathways NZ
Other research and resources
Continuing professional development

Clinical guidelines for managing high blood pressure

Cardiovascular disease (CVD) risk assessment and management for people aged 30 to 74 years without prior CVD is based on 5-year CVD risk prediction equations from the NZ PREDICT study, the NZ Primary Prevention Equations. See heart risk assessment for clinicians for details.

From Cardiovascular disease risk assessment in primary care, BPAC, NZ, 2018

Lifestyle interventions are recommended for every patient with a blood pressure ≥ 130/80 mmHg.
Calculate the patient’s 5-year cardiovascular risk to inform decisions about blood pressure-lowering medicines:

Blood pressure-lowering medicines are not recommended in patients with a risk < 5%
Discussions with patients about the benefits and harms of blood pressure-lowering medicines are appropriate in those with a risk 5–15% and a blood pressure ≥ 140/90 mmHg
Blood pressure-lowering medicines are strongly recommended for patients with a risk ≥ 15% and blood pressure ≥ 130/80 mmHg
Blood pressure-lowering medicines are recommended for patients with a blood pressure ≥ 160/100 mmHg regardless of cardiovascular risk.

If blood pressure-lowering medicines are initiated, a target ≤ 130/80 mmHg is recommended for most patients; however, this target should be approached with caution in older frail patients.
Angiotensin converting enzyme (ACE) inhibitors, angiotensin II receptor blockers (ARBs), calcium channel blockers and thiazide diuretics are all first-line blood pressure-lowering medicines.

Hypertension – the silent killer BPAC, NZ, 2020
What's new in cardiovascular disease assessment and management for primary care clinicians BPAC, NZ, 2018
Cardiovascular disease risk assessment in primary care – managing lipids BPAC, NZ, 2018
Cardiovascular disease risk assessment in primary care – the role of aspirin BPAC, NZ, 2018
Cardiovascular disease risk assessment and management for primary care Ministry of Health, NZ, 2018

Goodfellow MedCase – hypertension in older adults – finding the right target

The NZ Cardiovascular Disease Risk Assessment and Management for Primary Care 2018 (NZ CVD Guidelines) advise caution in treating blood pressure in older people due to concerns about risks such as falls or orthostatic hypotension.

The general target blood pressure of < 130/80 mmHg is suggested for those with few comorbidities and life expectancy > 5 years, but must be individualised based on likely benefits and risks of therapy.

This MedCase offers a framework for managing blood pressure in the older adult.

Goodfellow Gem – BP 140 treated to 120 – no increase in concern re falling

In an extra analysis of the SPRINT trial, where hypertensive patients were randomised to a treatment target of 140 mm Hg or 120 mm Hg, the concerns about falling were measured on the Efficacy Scale International questionnaire at baseline, six months, one year, and annually thereafter.¹

While there was an expected increase in falling concerns there was no difference between the groups randomised to 140 vs 120 mm Hg.

In the original paper there was a statistically significant increase in syncope but not in terms of injurious falls.² With older patients it's prudent to check their blood pressures sitting and standing but at the same time remembering that older patients have the highest CVD risk so treatment is a balance of benefit against harms.

References:

Regional HealthPathways NZ

Access to the following regional pathways is localised for each region and access is limited to health providers. If you do not know the login details, contact your DHB or PHO for more information:

Other research and resources

Results of the SPRINT trial have found that in high-risk CVD patients (20% risk of an event in 10 years), a target BP of 120 mm Hg showed improved outcomes (reduced CVD events and death) as compared with a target BP of 140 mm Hg. Read more: Tight BP control improves CV outcomes in high-risk patients
The British Hypertension Society (BHS) provides a list of blood pressure monitors they have validated.
Wiysonge CS, Bradley HA, Volmink J, et al. Beta-blockers for hypertension. Cochrane Database Syst Rev. 2017 Jan 20;1:CD002003. doi: 10.1002/14651858.CD002003.pub5. (Review) [Cochrane Plain Language summary]
Garjón J, Saiz LC, Azparren A, Elizondo JJ, Gaminde I, Ariz MJ, Erviti J. First-line combination therapy versus first-line monotherapy for primary hypertension. Cochrane Database of Systematic Reviews 2017, Issue 1. Art. No.: CD010316. DOI: 10.1002/14651858.CD010316.pub2. Conclusion: inconclusive, larger studies needed. [Cochrane Library]
Cochrane hypertension library

Continuing professional development

Online modules BMJ Learning

Managing hypertension in primary care An overview of the latest guidance on managing patients with hypertension and a guide to differentiating between primary and secondary hypertension. (1 hour) Sept 2016
What’s new in hypertension? This module describes recent developments in the management of hypertension and the practical implications for doctors working in primary care. (1 hour) Sept 2016
Hypertension – a guide to resistant forms and other special cases in primary care How to define resistant hypertension and treat the condition, with advice on changing or discontinuing treatment. (30 mins) Nov 2012
Hypertension – a guide to diagnosis in primary care A podcast with the latest advice on what risk assessment tools for hypertension are recommended and when to refer. (30 mins) April 2013
Practice pointer – treating hypertension in patients with medical comorbidities Two-thirds of patients with hypertension have at least one comorbidity. This module offers tips on managing high blood pressure in patients with chronic kidney disease, diabetes, heart failure, COPD, or asthma. (30 mins) Feb 2016