Hard-to-control high blood pressure (resistant hypertension) in older adults

The NHS says you are usually considered to have high blood pressure if your reading is 140/90 or higher when checked by a healthcare professional, or 135/85 or higher at home. It says blood pressure is very common in older adults, usually without symptoms, with age, family history, ethnicity, salt, weight, smoking, alcohol and long-term stress raising the chance. The BHF adds that arteries lose stretchiness, becoming stiff or narrow, which makes it easier for fatty material to build up and can trigger heart attack or stroke.

NICE guideline NG136 describes a stepped approach to treatment. If blood pressure remains uncontrolled in adults taking the best tolerated doses of an ACE inhibitor or an ARB plus a calcium channel blocker and a thiazide-like diuretic, the person is regarded as having resistant hypertension. The term describes how difficult the blood pressure is to control; it is not a judgement about the person.

NICE says that before considering further treatment for resistant hypertension, doctors should confirm elevated clinic readings using ambulatory (24-hour) or home blood pressure recordings, assess for postural hypotension, and discuss adherence, meaning whether the tablets are being taken as intended. The BHF says clinic readings can be higher than expected, especially if you feel nervous or anxious, which is why home readings or a 24-hour monitor may be used to calculate an average. NICE says to be aware that ambulatory and home measurements run 5 mmHg lower than clinic ones for diagnostic thresholds.

NICE advises measuring blood pressure lying and again after standing for at least 1 minute in people with symptoms of postural hypotension, including falls or postural dizziness; if the systolic pressure falls by 20 mmHg or more, or the diastolic by 10 mmHg or more, the cause should be considered. For older people this matters because over-treatment can cause falls, as described in our guide to orthostatic hypotension.

The BHF says that in most cases there is no specific cause, but in some people a cause is found, called secondary hypertension: examples include kidney disease, diabetes, obstructive sleep apnoea and some medicines such as oral contraceptives and some over-the-counter and herbal medicines. It says to ask a doctor or pharmacist if worried that any medicine or remedy might affect blood pressure. NICE advises considering specialist investigation in people with signs and symptoms suggesting a secondary cause.

The NHS adds that too much salt, alcohol, caffeine and being overweight raise blood pressure.

The NHS says healthy lifestyle changes help: a balanced diet, at least 150 minutes of exercise a week, losing weight, less salt, no more than 14 units of alcohol a week, less caffeine and no smoking. Most blood pressure medicines are tablets taken once a day, and you may need more than one. The BHF lists beta blockers, diuretics, ACE inhibitors, angiotensin receptor blockers and calcium channel blockers among them.

For confirmed resistant hypertension, NICE says to consider adding a fourth blood pressure medicine or seek specialist advice, and mentions considering a low-dose spironolactone for those whose blood potassium is 4.5 mmol/l or less, with blood tests for sodium, potassium and kidney function within a month of starting. These are decisions for the prescribing clinician; never add, stop or change blood pressure tablets without advice. NICE also says to use clinical judgement about treatment for people with frailty or multimorbidity and to discuss individual risk and preferences before starting treatment.

The BHF says the sensible clinic target is below 150/90 mmHg for people over 80 (145/85 mmHg at home), compared with lower targets for younger adults, because arteries become stiffer with age. NICE also separates targets for those under 80 and those 80 and over. In older people, medicines that lower blood pressure can contribute to dizziness on standing, so a home log of readings sitting and standing, and a medicines review, are useful. Guy's and St Thomas' notes that some blood pressure medicines can make postural hypotension more likely.

If you feel faint, have a fall, or notice confusion after a medicine change, tell the GP promptly. For chest pain, sudden breathlessness, or stroke signs, call 999.

The BHF says that when blood pressure is under control you will normally be monitored yearly along with a medicines review, and more often when starting new medicines or changing doses. It suggests keeping a diary of readings to help the team spot patterns. In England a scheme called Blood Pressure @home supports home monitoring, which you can ask your GP about, and the NHS says many pharmacies offer free checks for people aged 40 and over. Use a validated upper-arm monitor and take readings as the team advises.

The NHS says to get help from NHS 111 if you often have headaches or blurred vision, have chest pain that comes and goes, or have other symptoms you are worried could be caused by high blood pressure, and to call 999 for sudden chest pain or discomfort that does not go away, pain spreading to the arm, neck, jaw, stomach or back, or chest pain with sweating, feeling sick, light-headedness or breathlessness. The BHF says that if blood pressure is dangerously high you should seek urgent medical help.