Is my systolic blood pressure too high?

Is my systolic blood pressure too high?

Yes, if your top (systolic) number is 140 or more when a nurse, pharmacist or doctor checks it. At home, the line is 135.

Your bottom number doesn’t need to be high too. NICE’s GP summary says to suspect it when the top number stays at 140 or more, the bottom at 90 or more, or both.

Only the top number high? That’s isolated systolic hypertension.

Think of each heartbeat as a wave hitting a sea wall. The top number is the peak, as your heart pumps blood around your body. The bottom number is the dip, as it relaxes between beats.

A tall wave still strains the wall, even when the dip is normal. The NHS says high blood pressure puts extra strain on your blood vessels, heart and other organs. Left untreated, that raises the risk of heart attacks and strokes.

One high reading needs checking. Ask your GP whether you need home or 24-hour readings to confirm it.

Clinic or home: which top number counts?

These targets are for most people treated for high blood pressure. Kidney disease or type 1 diabetes can mean a lower one, so ask your GP which applies to you.

If a clinic reading is between 140/90 and 180/120, NICE offers a 24-hour monitor to confirm it. Home readings are the backup if that doesn’t suit you.

At home, the NHS says to take a reading, note it, wait 1 minute and take another. You usually do this twice a day, morning and evening.

Much higher at the surgery than at home? NICE calls a gap of more than 20/10 the white-coat effect. See how to measure blood pressure at home.

What causes high systolic blood pressure?

With age, the main cause is stiffer large arteries. A high top number alone is a late sign of stiffening arteries. It’s the main type of high blood pressure in middle and older age.

Picture a new garden hose that stretches with each surge. An old, stiff hose can’t, so each surge hits harder.

Common with age doesn’t mean harmless. It’s linked to higher risk of heart disease, stroke, heart failure, narrowed leg arteries, kidney disease and dementia.

The NHS says your chances go up with:

• getting older
• close relatives with high blood pressure
• a Black African, Black Caribbean or South Asian background
• a diet high in salt
• being overweight
• smoking or drinking too much alcohol
• feeling stressed over a long period

About 1 in 10 people with high blood pressure have a known cause. It may be a kidney, hormone or blood vessel problem, or some medicines.

Under 40? NICE says to consider a specialist check for a cause.

Take regular medicines? Ask your GP or pharmacist if any could be raising it.

Does isolated systolic hypertension need treatment?

Often, yes. NICE says to offer people with a top number of 160 or more the same treatment as people with both numbers high.

Organ damage means harm to the heart, brain, kidneys or eyes. Your 10-year risk is the chance of a heart or circulation problem. See cholesterol results for how that score works.

Why not just put it down to age? Because of a 1991 trial called SHEP. It followed 4,736 people aged 60 and over with a top number of 160 to 219 and a bottom below 90.

Over 5 years, 5.2 in 100 treated people had a stroke, against 8.2 in 100 on a dummy pill. That’s 36% fewer strokes.

It’s an old US trial of one set of medicines, so read it as evidence, not a promise. Never stop or change a prescribed medicine without your prescriber.

Pregnant? NICE has separate guidance.

Frail or living with several long-term conditions? NICE asks doctors to use their judgement on tablets and targets.

Ask your GP what stage your blood pressure is and whether tablets are worth discussing.

How can I lower my systolic blood pressure?

The NHS says lowering your blood pressure even a small amount can help cut your risk. For what works best, see exercise and blood pressure.

Thinking of a potassium salt swap? NICE says these shouldn’t be used by older people, people with diabetes or kidney disease, or pregnant women.

The same goes if you take some blood pressure tablets, such as ACE inhibitors or ARBs. NICE encourages these groups to cut salt instead. See salt substitute safety.

NICE also says not to offer calcium, magnesium or potassium supplements to lower blood pressure.

When to speak to a GP

High blood pressure does not usually cause symptoms. Only a check can show it. Speak to a GP if:

• Your top number is 140 or more at a pharmacy, or 135 or more on home readings. Ask about confirming it.
• You’re 40 or over and haven’t had it checked for more than 5 years. Get it checked at a pharmacy or GP surgery.
• You’re under 40 with high blood pressure. NICE says to consider a specialist check for a cause.
• Your clinic top number is 180 or more (or bottom 120 or more). NICE advises checks for organ damage as soon as possible. It advises a same-day specialist assessment if you also have new confusion or chest pain. The same goes for signs of heart failure or sudden kidney damage, or bleeding or swelling at the back of the eye.

Get help from NHS 111 if you often have headaches or blurred vision, or chest pain that comes and goes. Also get help for other symptoms you’re worried could be from high blood pressure.

Call 999 for sudden chest pain or discomfort that doesn’t go away, such as squeezing, pressure, burning or indigestion. Also call for pain spreading to either arm, your neck, jaw, stomach or back. Or chest pain with sweating, feeling sick, light-headed or short of breath.