People with high blood pressure in their 30s and 40s have a higher risk of dementia later in life — and a smaller brain, a study has claimed.
The research on more than 250,000 Brits found people with hypertension between 35-44 had a 61 per cent higher risk of developing the memory-robbing disorder later in life.
Doctors said their findings highlight the potential benefit of helping younger people control their blood pressure in reducing their dementia risk.
An international team of researchers, including academics from Australia and China, examined health records collected for more than a decade.
The findings are latest of a number of studies that linked high blood pressure in mid-life to dementia in old age.
Vascular dementia, the second most common form, is caused by reduced blood flow to the brain, which starves cells of oxygen and vital nutrients.
High blood pressure is thought to constrict vital arteries and speed up this process.
The findings should be of concerns to the millions of adults under-65s estimated to be living with hypertension in the UK.
In 2019 the British Heart Foundation estimated that 4million Britons in this age group have undiagnosed high blood pressure, with 1.3million under the age of 45.
Researchers found that people diagnosed with high blood pressure in their 30s and 40s had a higher risk of developing dementia later in life
High blood pressure is known as ‘the silent killer’ and leads to life threatening health risks such heart attacks and strokes.
Factors such as obesity, eating too much salt, smoking and drinking, lack of sleep, being of black African or black Caribbean descent, are believed to increase your risk of developing the condition.
Having a high-salt diet may disrupt your body clock and lead to an early death, study warns
A high-salt diet could be disrupting sleep patterns and long term health, a US study on mice suggests.
High-salt diets can raise people’s blood pressure, which in turn increases your risk of heart disease and stroke
Now new research from scientists from the University of Alabama suggests it could also disturb the body’s natural 24-hour cycle, called the circadian rhythm.
UJS researchers found a high-salt diet disrupted the internal body clocks in mice, and their findings could have implications for people
Disruption of the body’s circadian rhythm is thought to have various negative health impacts on people including their risk of developing mood disorders, cancer and even early death, the researchers claim
The scientists fed mice a high-salt diet and then measured their movement and brain activity throughout the day.
They found while mice on the high-salt diet did not do more or less activity they did not follow the same sleep pattern as normal mice.
Researchers found the high-salt mice had increased brain activity at night compared to the control group disrupting their internal body clocks.
‘Neuronal excitability at night could lead to decline or mistiming of sleep-wake, hormonal and physiological rhythms,’ the researchers wrote.
The researchers said an estimated 90% of the US population over 2-years-old have too much salt in their diet.
The NHS advises that adults should eat no more than 6g of salt a day (2.4g sodium) – that’s around 1 teaspoon.
A UK government report published in 2020 found that 69% of adults in England exceed the daily recommended amount of salt.
The researchers presented their findings today at the Seventeenth International Conference on Endothelin (ET-17).
The researchers compared the health data of 124,053 British adults with high blood pressure and 124,053 without the condition.
The medics than followed the patients’ medical history for up to 14 years and found 4,626 had developed some form of dementia.
They found people diagnosed with high blood pressure between 35-44 were 61 per cent more likely to develop dementia a decade later than people without high blood pressure.
The risk of vascular dementia, a type of dementia caused by impaired blood flow to parts of the brain, was 69 per cent more likely for people diagnosed with high blood pressure between 35-44, compared to those without the condition.
People who had a high blood pressure diagnosis between the age of 45-54 had a lower, but still significant, 45 per cent higher risk of vascular dementia compared to their healthy counterparts.
The doctors also compared MRI scans of brains from 11,399 Brits diagnosed with hypertension with scans from 11,399 Brits without high blood pressure.
These people were aged between 35-44 and 45-54 years-of-age at the time of the scan.
Medics found that people who had been diagnosed with high blood pressure had a smaller total brain volume than people without high blood pressure.
This shrinking of brain volume was worst in people who had been diagnosed with high blood pressure before they were 35.
The authors of the study believe that high blood pressure may be causing the brain to shrink in volume and this change in structure is connected to dementia.
However they added more research needed to be done to measure this trend in individuals over time, rather than a single scan.
Dr Xianwen Shang of Guangdong Provincial People’s Hospital in Guangzhou, China, said: ‘Our study’s results provide evidence to suggest an early age at onset of hypertension is associated with the occurrence of dementia and, more importantly, this association is supported by structural changes in brain volume,’ he said.
He added that helping people to tackle their high blood pressure early in life could spare them from a devastating dementia diagnosis in later life.
‘The findings raise the possibility that better prevention and control of high blood pressure in early adulthood could help prevent dementia,’ he said.
Another contributor to the study, Dr Mingguang He, professor of ophthalmic epidemiology at the University of Melbourne, said a screening program for high blood pressure could reap benefits for dementia prevention.
‘An active screening program to identify individuals with early hypertension and provide earlier, intensive high blood pressure treatment might help reduce the risk of developing dementia in the future,’ he said.
The researchers are now planning to further explore whether dementia diagnoses were preceded by conditions such as diabetes or a stroke in people who developed high blood pressure in their young adulthood or middle age.
Their latest findings were published in the journal Hypertension.
WHAT IS DEMENTIA? THE KILLER DISEASE THAT ROBS SUFFERERS OF THEIR MEMORIES
Dementia is an umbrella term used to describe a range of neurological disorders
A GLOBAL CONCERN
Dementia is an umbrella term used to describe a range of progressive neurological disorders (those affecting the brain) which impact memory, thinking and behaviour.
There are many different types of dementia, of which Alzheimer’s disease is the most common.
Some people may have a combination of types of dementia.
Regardless of which type is diagnosed, each person will experience their dementia in their own unique way.
Dementia is a global concern but it is most often seen in wealthier countries, where people are likely to live into very old age.
HOW MANY PEOPLE ARE AFFECTED?
The Alzheimer’s Society reports there are more than 850,000 people living with dementia in the UK today, of which more than 500,000 have Alzheimer’s.
It is estimated that the number of people living with dementia in the UK by 2025 will rise to over 1 million.
In the US, it’s estimated there are 5.5 million Alzheimer’s sufferers. A similar percentage rise is expected in the coming years.
As a person’s age increases, so does the risk of them developing dementia.
Rates of diagnosis are improving but many people with dementia are thought to still be undiagnosed.
IS THERE A CURE?
Currently there is no cure for dementia.
But new drugs can slow down its progression and the earlier it is spotted the more effective treatments are.
Source: Alzheimer’s Society