Could a routine trip to your local pharmacist potentially protect you from dementia?

This intriguing proposition comes from Adam Greenstein, a prominent authority on brain health and a professor at the University of Manchester. His research centers on the detrimental impact of high blood pressure on the brain.

Greenstein argues that high blood pressure is a significant yet often neglected contributor to dementia in the UK.

The Office for National Statistics reports that approximately 982,000 individuals were living with dementia in 2024. This number is expected to surpass one million by 2030, largely due to an ageing population.

“Hypertension is the most significant modifiable risk factor for memory loss in the UK,” Professor Greenstein asserts.

He advocates for regular blood pressure screenings for everyone from middle age onwards. If necessary, treatment with medication should follow. High Street pharmacists can perform these checks and refer individuals to their GP for further treatment if required.

High blood pressure is thought to contribute particularly to Alzheimer’s disease and vascular dementia, the two most common types of dementia, as it damages the tiny blood vessels in the brain, in turn causing a cascade of effects that can harm brain tissue.

This damage, known as small ­vascular disease in the brain (or ­cerebral small vessel ­disease), affects blood vessels that ‘sense and ­regulate blood flow to the brain’, explains Professor Greenstein.

An estimated 982,000 Britons were living with dementia in 2024, ONS figures show

Adam Greenstein, a professor of medicine at the University of Manchester, believes everyone from middle-age onwards should have their blood pressure checked regularly

‘When the blood pressure in your body goes up, it threatens to damage the brain, so these tiny vessels ­constrict to protect the brain – but by doing so they starve the ­neurons [the nerve cells in the brain] of fuel.’

These blood vessels also remove waste products from neurons, such as the proteins amyloid beta and tau.

‘High blood pressure inhibits this process when blood vessels constrict – and as a result, these proteins build up and create toxic brain cell-killing plaques’ – this is thought of as a hallmark of Alzheimer’s.

Research supports this theory that high blood pressure contributes to dementia.

A 2021 study in the journal Arteriosclerosis, Thrombosis, and Vascular Biology, for example, concluded that hypertension ‘accelerates or aggravates Alzheimer disease-like brain pathology in mice, such as toxic protein accumulations in the brain, neurons dying out and ­cognitive decline’.

Meanwhile, studies show that tackling hypertension with drugs may forestall this.

In research involving around 9,000 over-50s, published in the Journal of the American Medical Association in 2019, people who took blood pressure-lowering drugs for three years had significantly lower incidence of mild cognitive impairment (MCI), a precursor of dementia. Yet ­Professor Greenstein, who works with clinics across the North-West of England, says that many patients are reluctant to take blood pressure medication.

‘People don’t like it because they don’t experience any symptoms from the hypertension, but they can get side-effects from the tablets they are prescribed,’ he explains.

These side-effects can include dizziness, headaches, rashes and bad coughs.

‘They’d think differently about the medication if they realised that the pills can protect them from developing dementia – for which there is no treatment,’ he says, warning that lack of awareness about this is effectively ­fueling the rise of dementia.

‘One in three people in the UK has high blood pressure – but half of them don’t know they have it,’ he says.

Even among those who know they have hypertension, only half have their blood pressure ­controlled to the target, a blood pressure reading of less than 140/90 mmHg.

A big part of the problem is that people don’t make the link between hypertension and some of the less-obvious symptoms of creeping dementia, such as ­cognitive decline, balance issues, walking difficulties and mood changes.

Professor Greenstein says: ­’People [do] slow down as they get older. Their personalities might become blunted, they may feel depressed, tired and lack motivation. Memory and balance can be affected.

‘The problem is that these are [also] all features of small ­vascular disease of the brain.’

However, people don’t go to their doctor about these crucial warning signs.

‘So as a result, I am seeing ­people for memory loss and dementia when it is already 15 years too late for them: the brain damage they have from hypertension has become irreparable,’ says Professor Greenstein.

Nor are GPs and even NHS memory clinics on the lookout for hypertension as an underlying cause of cognitive problems.

‘Around 80 per cent of over-65s who have problems with memory loss and cognitive slowing will have high blood pressure or other marked cardiovascular risk ­factors,’ he says.

‘But doctors in memory clinics often won’t even measure patients’ blood pressure.’

Professor Greenstein adds: ‘People developing memory problems are told by their doctors that there’s nothing that can be done and to come back in five years’ time, because they believe that they don’t have any drug treatments for early symptoms – even though blood pressure pills may be the answer.’

Gill Livingston, a professor of psychiatry of older people at ­University College London, agrees, adding: ‘Some doctors and nurses think that the risk of high blood pressure is only to the heart. They are wrong – it can lead both to vascular dementia and Alzheimer’s.

‘But the great news is that there is excellent evidence that treating high blood pressure takes away the extra risk of dementia.’

Paresh Malhotra, a professor of clinical neurology at Imperial College London, concurs: ‘Although we think about high blood pressure being a risk factor for heart disease in particular, it’s clear that it is a risk for dementia too.’

He explains: ‘Very high blood pressure can be associated with acute confusion and neurological problems, but, untreated, even moderately high blood pressure can eventually lead to damage that leads to vascular dementia and increases Alzheimer’s risk.’

Professor Greenstein says that ignorance among medics of the threat from hypertension is a tragic waste of crucial time when it comes to preventing dementia – and is calling for all middle-aged and older people to have their blood pressure checked ­regularly and, if it is raised, to be ­prescribed tablets from their GP to control this.

His approach is backed by the Alzheimer’s Society charity. A spokesperson told Good Health: ‘Long-term studies have demonstrated that people who had high blood pressure from the ages of 40 to 64 are more likely to develop dementia in later life, particularly vascular dementia. Taking medication to lower blood pressure may help to reduce the risk.’

But it’s not just blood pressure pills that could help prevent dementia. According to two recent authoritative studies, weight-loss jabs containing GLP-1 drugs, such as Ozempic, Wegovy and Mounjaro, seem to reduce people’s risk, too.

In one study, at Case Western Reserve University in Ohio, researchers examined three years of health records from nearly 1.7 million Americans with type 2 diabetes.

Those who were taking semaglutide (brand names include Ozempic) had a significantly lower risk of developing vascular dementia than those taking any other type 2 diabetes medication, reported the Journal of Alzheimer’s Disease.

Meanwhile, a study of more than 60,000 patients in Taiwan who had type 2 diabetes and ­obesity, found that those who took ­semaglutide or tirzepatide (Mounjaro) had significantly lower risks of dementia, according to the journal JAMA.

The researchers wrote that GLP-1s ‘may have both neuroprotective and cerebrovascular benefits beyond managing blood sugar, and may potentially help improve long-term cognitive health’.

While the exact ­mechanism is unclear, Professor Greenstein argues that significant weight loss from taking fat jabs can improve patients’ blood pressure and overall cardiovascular health – which in turn can help prevent dementia.

Lifestyle changes can also boost our chances of avoiding developing dementia.

Experts writing in the Journal of the American College of Cardiology in 2020 concluded that an estimated one in three cases of Alzheimer’s are attributable to behavioural patterns that can be altered – especially a healthy diet and regular physical activity.

Professor Greenstein says: ‘If you understand dementia to be a problem of hypertension and heart disease, then it’s clear that doing things to protect your ­cardiovascular system also ­protect your brain: lose weight, eat healthily, exercise regularly – and go and get your blood ­pressure measured.

‘All you have to do is visit the High Street pharmacist next time you’re going to the shops.

‘They can measure your blood pressure – and refer you for medication to treat it, if necessary.’