Overview
is the force of blood pushing against the walls of the arteries. It is written as two numbers: the higher one is the pressure when the heart beats, and the lower one is the pressure between beats.
Blood pressure is called high when readings are 140/90 or above, measured at a clinic on more than one day. Home readings are usually a little lower, so 135/85 or above at home counts as high. A single raised reading is not a diagnosis.
Symptoms
High does not usually cause any symptoms, which is why it is often found during a routine check. It cannot be judged by how a person feels.
Very high pressure may cause severe headache, chest pain, breathlessness, vomiting, blurred vision, dizziness or nosebleeds. These are late signs and need medical attention rather than a wait-and-see approach.
When to see a doctor
See a doctor within a few days if readings are 140/90 or higher on more than one day, if has not been checked for a year, or if medicines have run out.
Causes
For most people there is no single cause. The pressure creeps up over years as the arteries stiffen with age, and salt, weight, activity, tobacco and alcohol all push it up or down.
Sometimes it follows another problem, such as kidney disease, a thyroid or adrenal disorder, or sleep apnoea. Some medicines, including certain painkillers and steroids, can also raise it.
Risk factors
- Older age
- A parent, brother or sister with high
- South Asian or African ancestry
- A diet high in salt and low in vegetables and fruit
- Being overweight, and carrying weight around the middle
- Too little physical activity
- Smoking or chewing tobacco
- Drinking a lot of alcohol
- Diabetes and kidney disease
Complications
Pressure that stays high wears down the arteries and the organs they supply. Over years it can lead to:
- Heart attack and
- Stroke and vascular dementia
- Heart failure and an irregular heartbeat
- Kidney disease and kidney failure
- Damage to the blood vessels at the back of the eye
Prevention
- Using less salt, and fewer pickles, papads, namkeen and packaged snacks
- Eating more vegetables, fruit and whole grains
- Being active for at least 150 minutes a week, such as a brisk walk on most days
- Keeping to a healthy weight
- Not smoking or chewing tobacco
- Limiting alcohol and very strong tea or coffee
- Having checked regularly, even when feeling well
Diagnosis
is measured with a cuff around the upper arm. Because readings vary, a doctor usually repeats the measurement on another day, or asks for readings taken at home or with a monitor worn for 24 hours.
Once confirmed, further tests look for a cause and for damage already done: blood tests for kidney function, sugar and , a urine test, an , and a look at the back of the eyes.
Treatment
Treatment starts with the changes listed under prevention. Cutting down on salt and losing extra weight often make a clear difference.
Medicines are added when the pressure is very high, when it does not settle with lifestyle changes, or when there is diabetes, kidney disease or heart disease. Several groups are used, and many people need more than one. They work only while they are taken, so they are meant to be continued.
Any other condition found, such as a kidney or thyroid problem, is treated as well, and the doctor sets a target to suit the person.
Myths and facts
Things people often say about this. Open each one to see what is true.
Myth“I feel perfectly fine, so my blood pressure must be normal.”What is true?
Fact
High blood pressure usually causes no symptoms at all. Many people find out only when it is measured, or after it has already strained the heart, kidneys or eyes. Feeling well is not a reading.
Myth“Blood pressure tablets are only for the days I get a headache or feel giddy.”What is true?
Fact
Medicines lower blood pressure only while they are being taken, so they are prescribed to be taken regularly rather than when symptoms appear. Doses should not be skipped, stopped or changed without asking the doctor who prescribed them.
Myth“Once you start blood pressure medicine you are stuck with it, and it spoils the kidneys.”What is true?
Fact
Blood pressure that stays high is itself a common cause of kidney disease, and lowering it protects the kidneys. Some people do need fewer medicines after losing weight, cutting salt and becoming more active, but that change is made by a doctor after checking readings.
Myth“Only tense, short-tempered people get high blood pressure.”What is true?
Fact
Stress can push a reading up for a while, but lasting high blood pressure is linked mainly to age, family history, weight, salt, inactivity, tobacco and alcohol. Calm and easy-going people get it too.
Questions to ask your doctor
Tick the ones you want answered and take them with you.
Common questions
My reading was high once. Does that mean I have hypertension?
Not necessarily. Blood pressure goes up and down through the day, and can be raised by pain, anxiety or simply by being in a clinic. A diagnosis needs raised readings on more than one occasion, often confirmed with readings taken at home or over 24 hours.
Can high blood pressure be cured so I can stop the tablets?
Most high blood pressure is controlled rather than cured. Losing weight, cutting salt, being active and stopping tobacco can lower the pressure enough for a doctor to reduce the medicines in some people. Stopping on your own is not safe, because the pressure usually rises again without warning signs.
Is it worth buying a blood pressure machine for home?
Home readings are useful, and many doctors rely on them. Choose a monitor that fits around the upper arm, sit quietly for five minutes first, keep the arm supported at heart level, and take the readings at the same times each day. Write them down and take the record to the appointment.
Does high blood pressure in pregnancy need different care?
Yes. Raised blood pressure in pregnancy needs close monitoring, because it can affect both mother and baby, and some blood pressure medicines are not suitable in pregnancy. Anyone who is pregnant, or planning a pregnancy, should tell their doctor before starting or continuing treatment.
