High Blood Pressure
At least six in 10 adults and up to one third of children with ADPKD have high blood pressure (also called hypertension). It may be the first sign of ADPKD, and may be diagnosed when kidney function is normal.
It is unclear why people with ADPKD have high blood pressure, but early and effective treatment is essential. Controlling blood pressure to the recommended target or level may slow the progression of kidney disease and lower the risk of aneurysms and stroke or heart attack. Some people can lower their blood pressure by changing their lifestyle, but you may also need medication to lower your blood pressure to the recommended level.
About blood pressure
Blood pressure (abbreviated as BP) is the pressure of blood inside the arteries every time your heart beats and pumps blood around your body. Blood pressure is measured in millimetres of mercury (mmHg), and is written as one number on top of or over the other:
- The first (top) number is your systolic blood pressure (SBP). This is reached when your heart beats and is the highest level of your blood pressure.
- The second (bottom) number is your diastolic blood pressure (DBP). This is reached when your heart relaxes between beats and is the lowest level of your blood pressure.
So if your systolic blood pressure is 130 mmHg and your diastolic is 80 mmHg, your blood pressure is said to be ‘130 over 80’, and is written as 130/80 mmHg.
High blood pressure
You have high blood pressure (or hypertension) if your blood pressure is consistently 140/90 mmHg or higher when it is measured by your doctor. High blood pressure is a problem for anyone because it means that your heart has to work harder to pump blood around the body, increasing your risk of heart attacks and strokes. But high blood pressure is a particular concern for people with ADPKD:
- It puts extra strain on your kidneys and may speed up the progression of kidney damage.
- It may also increase the likelihood that aneurysms or bulges in the walls of the blood vessels of the brain will burst.
Symptoms of high blood pressure
If blood pressure is very high or rises very quickly, it can cause headaches and problems with vision. However, most people with high blood pressure have no symptoms. So the only way to know if you have high blood pressure is to have it measured by your doctor or another health professional.
Diagnosing high blood pressure
You are more likely to have high blood pressure if readings are high when taken on several different occasions and when you are relaxed.
High blood pressure should never be diagnosed on the basis of a single blood pressure measurement, because your blood pressure varies throughout the day. It is usually lower at night and rises on waking. Blood pressure also rises after a meal or exercise, or if you are anxious or stressed.
Some people’s blood pressure is always higher when measured by a doctor or another health professional. To avoid this ‘white coat effect’, NICE now recommends that high blood pressure should be diagnosed based on numerous blood pressure readings throughout the day taken with a special blood pressure monitor (ambulatory blood pressure monitoring). You wear the monitor strapped round your waist and attached to a cuff wrapped around your upper arm. The cuff inflates and deflates automatically throughout the 24 hours to take recordings of your blood pressure during your normal daily activities.
Recommended blood pressure in ADPKD
In people with ADPKD, the recommended or ‘target’ blood pressure is generally 130/80 mmHg or less. However, if you lose large amounts of protein in your urine (proteinuria), you will usually be advised to aim for a blood pressure of 120/75 mmHg or less.
It is critical to control blood pressure in people with ADPKD. High blood pressure damages the kidneys, which in turn raises blood pressure still further. Research has also shown that tight blood pressure control helps to slow the progression of kidney disease in some people with chronic kidney disease. Lowering high blood pressure will also reduce your risk of a burst aneurysms or a heart attack or stroke.
Lifestyle advice to lower your blood pressure
You can sometimes reach your target blood pressure and avoid the need for medication by lifestyle changes:
- Lose any excess weight (the recommended body mass index is 20-25 kg/m2)
- Take regular aerobic exercise, but avoid activities that could injure your kidneys and cause cysts to bleed.
- Change to a low-fat diet that includes lots of fruit and vegetables.
- Reduce your salt intake (but avoid ‘low salt’ or ‘low sodium’ products. These contain potassium that is harmful if your kidney function is reduced or you are taking certain medications to lower your blood pressure).
- Reduce your intake of coffee, tea, cola and other caffeine-containing drinks.
- Give up smoking.
- Cut down on alcohol.
If lifestyle changes do not control your blood pressure, your doctor will suggest that you also take medication. You should continue with your healthy lifestyle, as it will help control your blood pressure and improve your general health. You may need more than one drug to keep to your target blood pressure, but the following are often used:
- ACE inhibitors or angiotensin-II receptor blockers (ARB) work by reducing the production of hormones that cause your blood vessels to become narrower. These drugs slow loss of kidney function in people with other types of kidney disease. Studies are currently under way to see if these drugs also slow disease progression in people with ADPKD.
- Calcium-channel blockers to relax the blood vessel walls and widen the blood vessels.
- Diuretics (water tablets) lower the blood pressure by helping your kidneys to remove more water and salt from your blood.
Once your blood pressure is at a healthy level, you will need to continue with your healthy lifestyle and your prescribed medication. If you have side effects, never stop taking your tablets without first talking to your doctor. There are many types of blood pressure-lowering medication, and you can work with your doctor to find the combination that is right for you. Monitoring your blood pressure You should have your blood pressure checked regularly by your doctor. You might also consider buying your own blood pressure monitor so that you can also keep an eye on your blood pressure at home.
- For more information and advice on blood pressure, including information on blood pressure monitors, go to the Blood Pressure Association website.
- You can read the latest guidelines on high blood pressure (hypertension) at the NICE website. There is a summary for patients, as well as more detailed information aimed at doctors.
The information on this page is under review by the PKD Charity using the accredited Information Standard process.
PKD Charity Helpline: The PKD Charity Helpline offers confidential support and information to anyone affected by PKD, including family, friends, carers, newly diagnosed or those who have lived with the condition for many years.
Disclaimer: This information is primarily for people in the UK. We have made every effort to ensure that the information we provide is correct and up to date. However, it is not a substitute for professional medical advice or a medical examination. We do not promote or recommend any treatment. We do not accept liability for any errors or omissions. Medical information, the law and government regulations change rapidly, so always consult your GP, pharmacist or other medical professional if you have any concerns or before starting any new treatment.
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