High Blood Pressure
NICE has produced guideline on high blood pressure.
This guide refines how we diagnose and manage blood pressure. The main change is use of home blood pressure readings or auotmated blood presure monitor recording to diagnose high blood pressure. Once diagnosed monitoring is still done by blood pressure recorded in the surgery by the doctor or nurse. Below is the edited highlight from the practice booklet on blood pressure record which has been updated.
What is blood pressure?
When a doctor or nurse checks your blood pressure with a cuff around your arm, they are checking the pressure at which the blood is pumped by your heart. When the pressure in the cuff is raised above the pressure in the blood vessel (artery) the pulse at wrist disappears. As the pressure in the cuff surrounding your arm is gradually released, when the pressure is equal or slightly lower than the pressure in the artery, the blood starts flowing and the doctor or nurse can feel the pulse. This is called the systolic (the top number) blood pressure. One can also hear the noise with the stethoscope as the blood starts flowing.
As the pressure is gradually lowered the noise disappears when there is no compression of the artery. The pressure at which the noise completely disappears is called the diastolic pressure. (Lower number in the blood pressure).
What are the causes of high blood pressure?
In most people we don’t find a cause for high blood pressure. Doctors call this ‘essential hypertension’. Hypertension is a fancy word for high blood pressure. In some (about 10% of the people with high blood pressure) the high blood pressure could be due to kidney problem or other causes.
Why lowering high blood pressure is important.
High blood pressure puts stress on the heart and blood vessels. This increases the risk of heart attack, and heart failure. High blood pressure also increases the risk of stroke, kidney damage and damage to circulation to the legs.
There is good evidence that lowering high blood pressure with medications lowers the risk of stroke by 35 to 40% and lowers the risk of heart attack by 20 to 25 %.
How to lower blood pressure without medications
- Regular exercise like walking briskly for 30 minutes or more on most days of the week.
- Maintain weight in the normal range. (BMI 20-25). See are you at risk of heart disease to know your BMI.
- Alcohol in moderation. Excess alcohol increases the blood pressure.
- Drink no more than 2 pints (for men) or 1 pint (for women) at a time.
- Avoid salty food and stop sprinkling salt on food.
- Consume at least five portions/day of fresh fruit and vegetables a day.
- Do not smoke
- Do not drink more than 5 cups of coffee or tea in a day. Avoid energy and cola drinks. Energy drinks have high content fo caffeine.
Can anything else be done to lower the risks from high blood pressure?
Your risk from blood pressure also depends on additional factors:
- Physical Inactivity
- High Blood Cholesterol
- Diabetes can markedly increase your risk from high blood pressure.
- Smoking not only increases the risk of heart attack and stroke but also increases the risk of lung cancer (and other types of cancer). One in two smokers die because of smoking related illnesses. Also you won’t get the full benefit from lowering your blood pressure if you continue to smoke.
You can assess your overall risk at QRISK website
Blood Pressure Readings
- BP Less than 140/90 when checked by your doctor. Your blood pressure is normal. Follow healthy life style. It is appropriate to check your blood pressure at least once in the next five years
- BP 180/110 mmHg or higher when checked by your doctor. You have high blood pressure. Your doctor may consider starting you on treatment.
- BP 140/90 or higher and pre-existing diabetes, heart, kidney or stroke disease. You have high blood pressure and need treatment. There is no need for home BP readings to assess.
- BP higher than 140/90 but less than 180/110. You need 24 hour blood pressure check or check your blood pressure at home for one week to decide if you have high blood pressure.
Home readings or 24 hour BP:
- Normal Less than 135/85
- Stage 1 hypertension 135/85 or higher
- Stage 2 hypertension 150/95 or higher
How to check blood pressure at home
- Sit quietly for five minutes, with your feet on the floor and your back well supported.
- Your arm should be resting on a flat surface, with the upper arm at the level of the heart.
- Position the cuff so that its midportion lies over the brachial artery. (Cuffs have marks to help with positioning.)
- Avoid caffeine (coffee, tea, cola and energy drinks), alcohol, smoking, and exercise for at least 30 minutes before taking your blood pressure.
- Each time take two blood pressure readings at least one minute apart. Record both BP recordings below.
- Check blood pressure twice a day preferably morning and evening. Check for 7 days.
Significance of BP readings
Normal blood pressure:
Clinic blood pressure less than 140/90 or home or 24 hour blood pressure recordings less than BP 135/85: This is normal blood pressure. No medication required.
Stage 1 Hypertension:
Home or 24 hours readings BP135/85 or above but not above 150/95 (then it is Stage2) and clinic blood pressure more than 140/90
You don’t need treatment unless you have one of the conditions listed below and aged 80 years or under.
- Heart disease or stroke (cardiovascular disease)
- Kidney disease
- If you are at higher risk of cardiovascular disease (ten year risk 20% or higher)
Stage 2 hypertension:
Home BP 150/95 or higher and clinic BP 160/100 or higher
You need treatment irrespective of age
Blood pressure targets with treatment
Home BP Age under 80: below 135/85
Clinic BP Age under 80: below 140/90
Home BP Age 80 and above: below 145/85
Clinic BP Age 80 and above: below 150/90
Ask the practice nurse or the doctor next time you visit the practice. We will be happy to answer them.
We recommend you buy automatic machines with cuff going round the arm. Do not buy machines that measure BP from wrist as they can be inaccurate.
The cuff going round the arm should be appropriate to the size of the arm. If cuff is too small blood pressure readings may be inappropriately high. If the cuff is too big for the arm BP can be inappropriately low. Automatic machines may be inaccurate if you have irregular pulse like atrial fibrillation.