Unlike about half of all adults over 60 in the UK, I don’t have high blood pressure. Or at least I didn’t until our daughter Charlie sent us a video of an Iranian drone flying low — and worryingly slowly — over the residential area in Dubai where her family live.

Parental anxiety aside, high blood pressure was on my mind this week after the release of updated guidance from the National Institute for Health and Care Excellence (Nice) on diagnosing and managing this all too common condition. The latest changes are more tweaks than big revisions, but they reinforce the trend for individualising treatment, and the importance of accurate measurement to clinch the diagnosis — something now typically done at home rather than in the consulting room.

We all need a healthy amount of pressure to circulate blood, oxygen and nutrients around our bodies, but if it is too high it starts to prematurely age the delicate lining of arteries, leading to problems ranging from an early heart attack or stroke to kidney disease, visual loss and dementia.

Nice estimates that at least one in four adults in the UK has high blood pressure. That’s about 12 million people, many of whom have no idea they have a problem. For every ten people who have been diagnosed there are thought to be another seven who remain undiagnosed and untreated. Might you be one of them?

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High blood pressure is normally symptomless, so the only way to find out if you have it is to measure it. And given that most people’s readings rise the minute a health professional approaches them with a cuff, home readings (see below) have become the gold standard for most GPs.

If the average of a series of home readings is under 135/85mmHg, you can relax and put the machine away for 6-12 months (Nice suggests a maximum of five years). If the average is 135/85 or above, contact your GP practice.

What happens next will depend on how high your readings are, your age and your general health and medical history, but it should always involve self-help measures such as weight loss, doing more exercise and cutting back on salt and alcohol. Nice advises avoiding too much caffeine and stopping smoking (which is unlikely to help your blood pressure, but giving up will reduce the risk of complications such as stroke and heart attack).

In milder forms of high blood pressure (from 135/85 to 149/94) these diet and lifestyle changes may be enough. However if they are not — or if someone is at particular risk because of other health issues, such as type 2 diabetes — medication is the next step. And it often requires more than one pill: about a third of people will be controlled by one medicine, another third will need two and the remaining third at least three.

There are myriad choices when it comes to blood pressure pills but most people will be prescribed one of the three main groups. Drugs ending -pril or -sartan, such as ramipril and losartan, reduce salt and water retention and relax blood vessels. The calcium channel blocker (CCB) family that often ends in -pine, including amlodipine, also dilate blood vessels. Then there are diuretics (water tablets), such as indapamide and bendroflumethiazide.

If you are over 55 or of black African or African-Caribbean origin, you should start with a CCB medicine. If you are under 55 or have type 2 diabetes, it should be a ramipril/losartan-type drug (ACEi/ARBs). And the target for good treatment is to get your readings down to a home average of less than 135/85, rising to under 145/85 for those over 80.

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Most people with high blood pressure will not have an identifiable underlying cause because it’s typically caused by age-related loss of elasticity in the walls of arteries, but you will still undergo basic investigations. These are likely to include a urine test (to look for blood and protein — signs of kidney damage), blood tests for diabetes and to measure cholesterol levels and kidney function, and an ECG to check for signs of heart strain/damage. And if you are under 40, or your blood pressure is not responding well to treatment, further investigations for underlying hormonal causes should be considered too.

Finally, if you do end up on medication, please take it properly. According to Nice, about half of all people with the condition are not as well controlled as they could be and don’t meet the targets, putting them at unnecessary risk of complications. Some of this will be down to the doctor, but much of it results from missed medicines and failure to follow dietary and lifestyle advice. Don’t be that person.

You can read the new guidance from Nice at nice.org.uk/guidance/ng136.

Measuring your blood pressure at home

• Sit quietly for five minutes and take two readings one minute apart. Repeat morning and night for a week and calculate the average. This should be under 135/85mmHG.
• The British Heart Foundation has a guide to home monitoring here
• Only buy a monitor that has been approved by the British and Irish Hypertension Society
• I would avoid wrist machines. Use a conventional type with an upper arm cuff — they tend to be more accurate