For discussion with your doctor
Should all over-50s be taking blood pressure drugs?
When I was young, carefree and skinny, I was proud that my blood pressure was at the lower end of the healthy range, no matter how much salt I poured onto my chips. Now I’m 58, a bit fatter and a lot more stressed, it’s crept up a bit. But, at around 122/85, my blood pressure is still regarded as normal. In fact, the average adult in the UK has blood pressure similar to mine and I’ve certainly never considered taking medication for it.
Yet according to consultant cardiologist Professor Kazem Rahimi, prescribing blood pressure-lowering drugs even to midlifers like me could help prevent thousands of strokes, heart attacks and other cardiovascular problems every year.
Rahimi is the lead researcher of a large study, just published in The Lancet, which looked at the impact of the drugs across a range of blood pressure levels on the risk of heart and circulatory diseases. Data from around 360,000 people aged 21 to 105 from 51 randomised trials was analysed and blood pressure-lowering was found to be effective at preventing disease at all ages, even when a patient's blood pressure levels were as low as 120/60. This is well within the healthy range, and even lower than mine.
In April, Rahimi published a similar study, which suggested that more than 20,000 heart attacks, strokes and cases of heart failure could be prevented every year if drugs to lower blood pressure were prescribed to people with normal blood pressure.
His research found that a 5mmHg reduction in blood pressure, a drop that is usually achievable with medication, led to a 10 per cent fall in risk for a major cardiovascular disease, a 13 per cent reduction for both stroke and heart failure, 8 per cent for coronary heart disease and 5 per cent for death from cardiovascular disease.
He says: “The perception has been that treatments should be reserved for those who have higher blood pressure. And that is not true.
“It’s true that the higher your blood pressure, the higher your risk. Our study shows that reducing blood pressure from let’s say 150mmHg to 140mmHg will have roughly the same relative effect as reducing it from 130mmHg to 120mmHg, irrespective of age. Clinical guidelines should be changed to reflect these findings.”
My GP is unlikely to offer me a prescription any time soon, though. In the UK, the NHS defines ideal blood pressure as anything between 90/60 and 120/80 and only those with a reading of 140 or more are eligible for blood pressure-lowering drugs.
Also, I would only be offered medication at this point if I also had other cardiovascular risk factors such as obesity, diabetes or high cholesterol. Otherwise, my blood pressure would need to be consistently over 160/90 to merit a prescription. If I was aged over 80, I wouldn’t be considered for drug treatment unless I hit 150/90, no matter what my other conditions might be.
Why? Traditionally it’s been thought that it’s both inevitable and normal for our blood pressure to rise as we hit midlife and older. Some specialists have thought that increased pressure might help keep the brain oxygenated and that lowering it could cause dizziness and falls. However, Rahimi’s study found that medication cut the risk of a heart attack among people aged 75 to 84 by almost 10 per cent. Risk of stroke and death from heart disease also dropped by eight per cent and heart failure by 18 per cent, all without any major side effects.
The idea that higher blood pressure is harmless as we age is, he says, both wrong and potentially dangerous. Not only does it increase the risk of heart disease and stroke, high blood pressure in midlife also increases the risk of vascular dementia. But if the argument for offering equal treatment to older people appears irrefutable, the concept of offering pills to ‘healthy’ people of any age is more controversial. However, says Rahimi, many of us, even if we think we are healthy, are walking around with chronically elevated blood pressure because of our modern lifestyles. “‘Normal’ is usually defined as the average of the population,” says Rahimi. “But when the whole population is exposed to an industrialised lifestyle that increases blood pressure, concluding that their average is healthy is likely to be misleading.” Factors that push up blood pressure include salt, alcohol, obesity, lack of exercise and even traffic noise. In remote populations that are not exposed to any of these things, he says, “the average blood pressure is typically around 95/65 across all age groups.”
Rahimi admits that “people will be puzzled by the finding that blood pressure-lowering is not just for people with high blood pressure.” But, he says, “treatment should be viewed as a tool to prevent cardiovascular disease, rather than just for lowering blood pressure per se.”
That does not necessarily mean, he says, that everyone should be taking pills. However, for a small number of people they could form a useful insurance policy against future ill health. Doctors, he points out, already have standard ways of assessing cardiovascular risk using a combination of measures including weight, cholesterol levels, alcohol use, exercise habits and diabetes. He says that for people with some of these risk factors, but normal blood pressure, current prescribing guidelines “could lead to withholding effective treatment from a fraction of high-risk individuals.”
It is not #multimorbidity that lowers #BloodPressure but our diagnostic and treatment biases in healthcare. The lack of a more rapid decline in BP in multimorbidity provides some reassurance for BP treatment in these high-risk individuals.https://t.co/XP1ZKQC5Ie pic.twitter.com/uRQVEBP9dL
— Kazem Rahimi (@kazemr) June 30, 2021
Not everyone is sure we yet have the evidence we need to recommend offering medication to people without high blood pressure. Dr Margaret McCartney is a GP and author. She says that the trials included in The Lancet study “were almost all of people who had either what we would already regard as high blood pressure, or some other condition as well – such as a heart attack or stroke. These patients are already offered treatment. As for treating blood pressure in healthy people as low as 120/60, there are several problems. There were no trials included in the analysis which routinely did this – and no mention of how frequent side effects would be. If we are looking at ways to reduce our overall risk, there may be more effective ways that don't just lower cardiovascular risk, but our other risks as well – for example, our weight, our diet, smoking and alcohol. It may be easier for doctors to say ‘take a pill’ but trying to reduce the risks that populations have, like obesity or a lack of active travel options like safe cycling, is important."
But while Professor Rahimi admits that the evidence is not yet “perfect”, the medical issues at stake are urgent. He says, “Every day, doctors are facing the following scenario: a patient who has a substantially elevated risk of heart disease and stroke but with a blood pressure that is deemed normal or nearly normal. It’s not the case that they will offered blood pressure lowering medications. Even in people with risk factors or previous cardiovascular disease, NICE - and several other international guidelines - demand that blood pressure is above a threshold before treatment is considered. Our study clearly challenges this and provides evidence against these restriction.”
As for side effects, he says, “there is no evidence to suggest that if you reduce blood pressure from 120 to 110 mmHg you will get more side effects than when it is reduced from 160 to 150 mmHg”. That’s not to say that cycling or eating better aren’t good for us, or shouldn’t be encouraged. “We need both public health and medical interventions,” he says. “The two are not mutually exclusive.”
I ask Professor Rahimi if he thinks that medication might benefit me, as a middle-aged non-smoker with a just-about-normal BMI thanks to a post-lockdown diet plus regular yoga and dog walking, but slightly high cholesterol and a fondness for wine. He politely declines to diagnose me, but he doesn’t say no. The realisation that my ‘normal’ blood pressure is not the same as an ‘optimal’ reading has shaken me out of my complacency. I’m planning to swap my beloved salt for a low sodium replacement – which a new study has shown can cut the risk of strokes and heart attacks – eat better, tackle stress and lose a few more pounds.
After all, it appears that when it comes to blood pressure, less is definitely more.
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