Blood pressure targets at 70 are not the same as at 45

For most of the twentieth century, the medical view of blood pressure in older people was relaxed to the point of negligence. A rising systolic reading was regarded as a normal accompaniment of ageing — arteries stiffen, pressure rises, and treating it aggressively in a seventy-five-year-old seemed likely to cause more harm than it prevented.

That view has been substantially reversed, and then partly qualified again. The current position is more nuanced than either the old complacency or the newer enthusiasm, and it depends heavily on the individual in front of you.

What changed

Two trials did most of the work. HYVET, published in 2008, randomised adults over eighty with systolic pressure above 160 to treatment or placebo. It was stopped early because the treatment group had significantly lower mortality. That settled the question of whether treating hypertension in the very old was worthwhile: it was.

SPRINT, published in 2015, went further. It compared a systolic target of under 120 to the conventional under 140 in adults at elevated cardiovascular risk, including a large subgroup over seventy-five. The intensive arm had significantly fewer cardiovascular events and lower all-cause mortality, and the benefit in the over-seventy-fives was, if anything, larger than in the younger participants. That trial was also stopped early.

The consequence was a wave of guideline revision. The American College of Cardiology and American Heart Association redefined hypertension downward in 2017, to 130/80. European guidance moved less far, and the UK's NICE has retained a somewhat higher treatment threshold, particularly for the over-eighties.

The measurement caveat that keeps getting lost

SPRINT measured blood pressure using an automated device, with the patient seated alone in a quiet room, after a period of rest, with no clinician present. This is not how blood pressure is usually measured in a clinic, and it matters: unattended automated readings typically run 5 to 15 mmHg lower than a conventional clinic reading in the same person at the same moment.

So a SPRINT target of 120 is not the same as 120 taken hurriedly in a GP's room with a nurse in attendance and a full waiting area outside. Applying the trial's numbers to a clinic reading risks treating people considerably harder than the trial actually did. This is one reason home monitoring, done properly, has become more central to management.

Where the qualification comes in: frailty

SPRINT excluded people with diabetes, prior stroke, dementia, nursing-home residence and significant frailty. That is a large fraction of the older population, and it is precisely the fraction in whom aggressive treatment is most likely to cause harm.

The specific harm is orthostatic hypotension — blood pressure that drops sharply on standing, producing dizziness, unsteadiness and falls. A hip fracture in an eighty-five-year-old carries a one-year mortality that is comparable to many cancers. Preventing a stroke in ten years is not obviously worth causing a fracture next month.

So the practical approach in older adults now involves measuring blood pressure both sitting and standing. A drop of 20 mmHg systolic or 10 mmHg diastolic within three minutes of standing is the usual threshold for concern, and its presence should slow any push toward lower targets considerably.

Deprescribing is a legitimate intervention

Blood pressure often falls naturally in the last years of life, as cardiac output declines and weight is lost. A regimen that was appropriate at seventy-two can be actively dangerous at eighty-six, and medication lists have a strong tendency to accumulate rather than to be pruned.

The OPTIMISE trial tested exactly this — reducing antihypertensive medication in adults over eighty with controlled blood pressure — and found that most participants remained adequately controlled at twelve weeks on fewer drugs. Deprescribing, done deliberately and with follow-up, is not neglect. It is part of good management.

The non-drug measures still work

They work less than people hope and more than people who have given up assume. Reducing sodium intake produces an average systolic reduction of a few mmHg, with larger effects in salt-sensitive individuals, who are disproportionately older and disproportionately of African descent. The DASH dietary pattern produces reductions comparable to a low-dose drug in trial conditions. Regular aerobic activity lowers systolic pressure by roughly 5 to 8 mmHg. Losing excess weight lowers it by roughly 1 mmHg per kilogram, up to a point. Alcohol reduction helps in those drinking heavily.

None of these replace medication in someone with substantially elevated pressure. Several of them together can reduce the dose required, which in an older adult on six other drugs is a real benefit.

What to ask at your next appointment

What is my target, and why that number for me specifically? Has my blood pressure been checked standing as well as sitting? Am I on the lowest number of drugs that achieves this? And if I have been on the same regimen for five years — is it still the right one?

These are unremarkable questions. They are also, in a ten-minute appointment, the ones most likely to go unasked.