- General advice is here,
- Blood pressure 130/80
- Take control of blood pressure
- 'Home monitored' blood pressures
- White coat & fluctuating BP
- Proteinuria and blood pressure
- Non-steroidal anti-inflammatory drugs
- How can you lower your BP?
- When are BP checks needed?
- Blood pressure control cycle
- Which drug
Blood pressure and diabetes
This page is best viewed printed out. If you are a patient you can take this to your practice nurse so it can be used for ideas.
Complications from diabetes develop much more quickly if blood pressure is high. This is illustrated in the graph opposite, from the UKPDS £23 million study. Lifestyle has a major impact on blood pressure, but medication is generally needed.
- Each 1 mmHg of blood pressure rise causes a 1.2% increase in the number of problems.
- In practice for instance, if you have diabetic maculopathy, a serious form of retinopathy, you need a very low blood pressure to stop (or slow down) your sight getting worse.
- Unfortunately some people become ill if their blood pressure is too low (dizzy, occaional falls), so like everything else in diabetes, the blood pressure is a balance. The balance is between keeping well and avoiding diabetic problems, versus the side effects of the tablets, too low a blood pressure and becoming dizzy, and too many trips to the doctor.
- Worldwide, blood pressure is undertreated see . Long term control is needed (NEJM 2008). also.
- Candersartan reduced retinopathy progression by 18-34% (BMJ 10) DIRECT .
- White coat hypertension does contribute to retinopathy and does need treatment 2008.
If you have high blood pressure, take control. Buy a machine (in Birmingham, Lloyds Chemists sell good machines for ~£15). If your blood pressure is high and you are trying to lower it, check the pressure daily, and keep it below 140. Doctors need to test, and electronic systems can be helpful.
- a blood pressure below140. This is the systolic BP, the 'top' figure. This is the general target
- Generlly the lower the better as long aas there are no side effects(
- Depression & anxiety increase BP.
- Aim for 130/80 (clinic BP) if well, perhaps slightly higher if you have lots of medical problems. About 5-10 mmHg lower for home blood pressures. Testing at home can be helpful JHH 2012.
|Blood pressure upper targets, the lower the better|
|130/80||125/75||general; ambulatory night time BP <120|
|115/.....||105/...||to prevent deterioration in renal function (ideal), as long as there are no side effects|
- All the blood pressure measurements in this website relate to 'clinic' or 'hospital' blood pressures.
- Home monitoring blood pressures should be 10mmHg (systolic) and 5mmHg (diastolic) lower see than these 'clinic' pressures.
- Targets are only achieved in 20%. Blood pressure rises significantly in type 1 diabetes as kidney disease (nephropathy) develops (EASDec 2002). 2010 recommendations.
There is a considerable risk of strokewith this type of hypertension. Many people say their blood pressure is normal at home or at their doctor's, but high in the eye clinic. Such fluctuating blood pressures are still harmful, indeed twice as harmful as regular hypertension. Lancet 2010 Masked blood pressure.
If you can achieve low levels, then your kidney function may not get worse. If you cannot achieve these levels, and you have protein in your urine, your kidney function may slowly get worse. Even lower blood pressures help further, see here.
NSAI (non-steroidal anti-inflammatory) drugs, such as ibuprofen (eg Nurofen), are not recommended for long term use. They increase blood pressure.
No one is telling you what to do, and your lifestyle is generally under your control. But a healthy lifestyle is essential if you want to keep your sight and your kidneys. Your doctor can arrange for help for you to stop smoking, and help if you are alcoholic.
Professionals are there to help when they can, but if you have no arthritis yet decide not to walk for 30 minutes a day, inevitably your health will suffer. 2 hours a day is the ideal time spent exercising if you are overweight, 1 hour if not. You may need 4 different tablets to lower blood pressure, as below. Lifestyle factors.
|Exercise||such as walking or swimming, 30 minutes a day|
|salt||Not adding much to food, and reducing amounts of processed food with salt already added. Afro-Caribbeans are very salt sensitive, so reduction is important.|
|smoking||20/day triples the likelihood of problems from diabetes|
|losing weight||exercise more and eat less. Losing 10% weight will cause a marked reduction in blood pressure|
|alcohol||contributes to high blood pressure: stick to less than 2 units/day. Each unit = 2.2 mmHg blood pressure.|
|a healthy diet||helps in the long term, as does a cholesterol less than 5.0. Red meat increases blood pressue 1.2mmHg. Omega 3's are helpful. Flavenoids|
|some drugs put blood pressure up||non-steroidals put blood pressure up e.g ibuprofen|
|Kiwi fruits||lower Bp|
keep a record of your blood pressure
Keep a record. Why not carry the details with you for all your nurses and doctors to see? The most accurate pressure is that measured by your practice nurse. Results are higher when taken by doctors!
It is not usually recommended necessary to test your pressure at home with your own machine, but it can be very helpful if you have hypertesnion. Do not worry if you cannot reach the ideal blood pressure of 130/80 or below.
Some people, particularly if you have lots of medical problems, may not be able to reach such a blood pressure. Discuss this with your doctor or nurse.
Each 10 mmHg rise in blood pressure causes and extra ~12% deterioration in retinopathy & kidney damage.
If you have high blood pressure and you are working with your doctor and nurse
trying to lower it, a test every 2-6 weeks is helpful. Naturally tests should
be more frequent if it is very high, or you need it very low because of your
Similarly, if you are well and your pressure is low (especially children), every 3-6 months is fine. Keeping your pressure low slows down the development of other problems that you may get with diabetes such as eye, feet, kidney, nerve, and heart problems.
Some people with high blood pressure can achieve a lower blood pressure by reducing salt intake. The difference occurs because people have different metabolisms, and these may be genetically determined by the genes you have inherited from your parents. (Salt sensitivity, review).
33% salt reduction from the current average level would reduce blood pressure 4mmHg (NEJM 2009..but this is an average, it will be much more in some people).
|Sources of salt in our diet|
|15% of contribution from salt||natural in fresh food|
|15% of contribution from salt||what we add at the table|
|70% of contribution from salt||from convenience and processed food, most of which have salt added|
|Amount in processed food|
|1% of the foods content||in cereals, such as corn flakes|
|>2% of the foods content||vegetarian canneloni (tesco's); Special K cereal|
If you eat food with a lot of salt it tastes awful without....... for about 4 weeks, after which you should get used to the new taste. Then the food you used to like will taste salty! This is not like cigarettes, which can be very difficult to stop.
- Losalt is a substitute, but is still 30% regular salt (sodium chloride). It is not recommended if your kidneys are damaged.
- Sea salt is still sodium chloride and just as harmful if you have too much.
- Some Afro-Caribbean diets are very salt rich, and Afro-Caribbeans are very sensitive to salt and get a higher rise in blood pressure.
- herbs and spices make food tastier but have no blood pressure effect, so they are much safer..
A healthy lifestyle delays the development of high blood pressure. However, even with the healthiest lifestyle, and perhaps partly because of genes you have inherited from your parents, most people with diabetes develop high blood pressure eventually. At this stage drugs are needed to lower the pressure to prevent complications (as above).
If you start a new drug, and it makes you feel very ill, stop it right away and see your doctor. If you notice an effect that is not so serious, read the drug information leaflet with the drug.
Some side effects are specific to the drugs, and some of these are mentioned below. Some are more general, such as dizziness when you stand up.
Compliance improves if the drug treatment is explained. Compliance is normally about 50%. Simply prescribing the medication is not sufficient. Patients need to know a little about the drugs, how they work, and why they are needed.
A stepped approach is helpful as below. Patient educational status, belief in taking the drugs, and encouragement by the family were important. A training program for doctors helps!
- Generally proceed in a step wise fashion, adding medication, increasing or doses of tablets according to blood pressure drop needed.
- Your doctor may also change your tablets if they produce side effects. Five blood pressure medications may be needed.
- Decrease doses or withdraw drugs if unwanted side effects develop.
- review patients every 2-6 weeks according to how high the blood pressure is or how important (macular oedema needs urgent attention)
- at each visit if the blood pressure is higher than needed the dose is increased to the maximum appropriate, or the next drug is added
- naturally side effects will necessitate drug dose reduction or even stopping
- side effects
- dizziness is a general problem such as too low a blood pressure
- other problems are more specific, such as ankle oedema from calcium channel blockers
- Need annual tests
- urinalysis blood/protein
- total cholesterol/HDL (non-fasting): triglycerides (fasting);
- urea & creatinine
- dilated fundoscopy (eye check with dilated pupils)
- tailor drugs to patient...calcium channel blockers less helpful if patient constipated; thiazides not ideal if sexually active
|Drug step 1||Precaution||Details|
|step 2 add another in the group||Precaution||Details|
|step 3 add||Precaution||Details|
|step 4 add||Precaution||Details|
Most people taking tablets for high blood pressure feel perfectly well and have no side effects from the tablets. Their only problem is remembering to take the tablets! After starting new treatment it is only natural to think that any new symptoms must be caused by the treatment.
If you do seem to have side effects, discuss them with your doctor who will be able to tell whether or not the tablets are to blame.
Most of the tablets for treating high blood pressure can also be used for other heart conditions. So don't be surprised or worried if you know someone with a different condition who is taking the same tablets as you. Naturally medication should be stopped if you are sure it is making you ill, and discuss problems with your doctor.
|sore or watery eyes||Blood pressure tablets may make these worse, especialy furosemide.|
|other tablets||Possible reaction with other tablets, including some that are available without a prescription, including herbal remedies. Check with your doctor or pharmacist before you take them.|
|Rash||May develop soon after you start a new treatment. Report this to your doctor. You may have developed an allergy to the tablets.|
|light-headed or dizzy||If you
feel, or if you faint. These effects may be particularly noticeable when
you get up from bending or lying down, or if you are older.
If these side effects are severe, it may be that your tablets have reduced your blood pressure too much.
Tell your doctor who might reduce the dose of the drug or give you different tablets.
|potassium||ACEI inhibitors and ARBs rarely cause high potassium levels, (mre common with kidney problems). Potassium levels should be checked one week after starting or increasing dose.|
ACEI stands for 'angiotensin
converting enzyme inhibitors'; they work by stopping the conversion of
an inactive substance in the blood called angiotensin 1 to the very potent
angiotensin 2, which produces spasm and constriction of the blood vessels.
Angiotensin receptor antagonists (ARB, also called angiotensin II inhibitors) are likely to be just as effective as ACEI inhibitors (ACEI).
Patients using ACEI and ARBs need monitoring with U & Es
(kidney function and electrolytes) tests. They work partly by making the
walls of the arteries relax and dilate. The first dose can cause quite a
large drop in blood pressure, so this dose is best taken last thing at night.
You should not take ACEI inhibitors if you are pregnant.
ACEI & ARB are generally recommended for diabetes, even if there is no hypertension (see). They reduce progression rate 50% in some studies. This may be because there are angiotensin receptors in the retinal cells.
Unwanted effects of ACEI/ARB
ACEI/ARB are generally better tolerated by patients than most of the other drugs. However, they can cause a marked fall in blood pressure, especially when first used by people who are also taking diuretics. They may also affect the function of the kidneys if this is already abnormal. When your doctor starts the treatment, they will take care to start you on a low dose and will regularly check your blood, as above.
Some ACEI may affect your sense of taste and cause skin rashes and, very occasionally, a major allergic reaction. Some people develop a persistent, dry, irritating cough. If this happens, you should tell your doctor about it.
ARBs are generally better tolerated, although some are more expensive. Also, whilst much research has identified the benefit of ACEI, there is less evidence about ARBs. However, concerning blood pressure and diabetes, they are generally felt to be as effective.
May cause ankle swelling. These are now usually added to patients already taking ACEI/ARBs. Most people use amlodipine 5-10mg OD
- suggested drugs bendrofluazide 2.5mg or 1.25mg OD
- to pass water more often when started
- slight rise in sugar level
- lower potassium (occasional blood test needed)
- lower blood pressure (dizzy)
- precipitate gout
These are common drugs, now usually added when patients are taking ACEI/ARB and calcium channel blocker. They were previously first line treatment in non-diabetics. Very low doses (such as bendrofluazide 1.25mg) may be better, but at present these are only available as combination drugs. The doses opposite may increase blood fat levels, sugar levels, uric acid, and lower potassium levels. These are often known as the 'water pills'. They work on the kidneys, helping them to pass more salt and water into the urine. This triggers hormone reactions which lower the blood pressure. If passing water too much makes your life difficult or leads to incontinence, tell your doctor.
Altogether there are three types of diuretics. These are: thiazide, loop diuretics, and potassium-sparing diuretics. If you take a thiazide or loop diuretic, your doctor will arrange a blood test a few weeks after you start, to check the potassium level in your blood. If this is getting low, you will be given potassium supplements, or a potassium-sparing diuretic will be added. If you are diabetic, you may find that diuretics raise your blood sugar levels.
Loop diuretics include frusemide or bumetamide, and are especially useful in diabetic nephropathy, often combined with an ACEI inhibitor.
If potassium <4.6, spironolactone 25mg od (increasing to 50mg od). This can give breast tenderness and gynaecomastia: if this happens substitutes are available. If more than 3 drugs are needed, this is classified as 'resistant hypertension' BMJ 2012, NICE 2011.
If potassium >4.5, increase the dose of thiazide diuretic
|unwanted / not recommended||
These are also first line agents in non-diabetics. Beta-blockers as a whole are less effective in Afro-Caribbeans. They work by stopping the action of adrenaline. This reduces the pulse rate and limits the amount the pulse rate rises when you exercise.
Serious side effects are rare if beta-blockers are used with care. Beta-blockers should not be stopped suddenly without medical advice. If you also have angina, stopping beta-blockers too quickly can make it worse. If you have diabetes, you need to be aware that beta-blockers may suppress the usual warning signs of low blood sugar - such as palpitations and tremor.
If you stop taking beta-blockers, you may feel as if your heart is beating abnormally fast or heavily (palpitations). Ask your doctor for advice if this continues.
Vaso-dilating beta-blockers may be preferable see.
Other drugs include those acting centrally on the brain, such as physioten, or doxazocin.
The effect of drug treatment may take 2 months to be apparent. But if there
is severe retinopathy with significant hypertension 1-2 week follow up may
be best, to check for side effects and that the blood pressure is dropping.
Once stabilised, BP can be checked every 3-6 months. Electrolytes should be checked prior to drug treatment. If diuretics are used then potassium should be checked after 4 weeks treatment. Special monitoring is required for ACEI inhibitors.