Study reveals clearer picture of hypertension’s impact on brain health

University of New South Wales (UNSW) researchers have used artificial intelligence (AI) technology to demonstrate the link between high blood pressure and accelerated ageing of white brain matter.
 
The study, published this week in Hypertension, utilised novel ‘3D-CNN Imaging’ – a type of AI deep learning modelling – to analyse brain MRIs from nearly 40,000 people, finding that high blood pressure is an independent risk factor for the accelerated ageing of white matter in the brain.
 
 Scientia Professor Perminder Singh Sachdev, who led the research out of UNSW’s Centre for Healthy Brain Ageing (CheBA), believes the research will allow clinicians to better identify common changes to white matter seen on MRIs previously thought to be insignificant.
 
It could allow earlier detection and treatment of individuals at risk for dementia.
 
‘It will improve our understanding of what we should be looking for on [brain] imaging,’ he told newsGP.
 
‘There is currently a tendency to underplay and ignore age-related changes and small vessel disease in the white matter of the brain.
 
‘We should be looking more closely [to improve] vascular risk factors in these people.’
 
The study also used AI modelling to determine polygenetic risk of hypertension-related accelerated ageing of white brain matter – ie, how someone’s genetics predispose them to accelerated brain ageing from high blood pressure.
 
Meanwhile, age-related associations found in the study suggest that significant hypertension-related brain ageing has already occurred by middle age, which highlights the important role Australian GPs have in providing proactive preventive care across all age groups.
 
Brain health has huge health implications for Australia.
 
According to the latest statistics from Dementia Australia, dementia is the second leading cause of death in all Australians and may soon become the leading cause of death.
 
Currently, more than 421,000 Australians live with dementia, 29,000 of whom developed it prior to turning 50. Alarmingly, these total number of people with dementia is predicted to increase to over 812,500 in the next 30 years unless there is a major medical breakthrough, with 41,000 expected to will develop it at a younger age.
 
Brain Awareness Week has also been marked by the appointment of GP Dr Marita Long as Dementia Australia’s new medical advisor.
 
Dr Long says GPs play an important role in the diagnosis, treatment and management of dementia, but need more support from the health system in the form of more rehabilitation services and  better remuneration for the significant time and effort spent by GPs undertaking preventative care.
 
‘There is no curative treatment for dementia and when there is no cure, prevention is everything,’ she told newsGP.
 
‘GPs are really good at preventive health, but Medicare doesn’t properly reward this. We need to improve the healthcare system and shift the focus from high-end interventions to good primary care.
 
‘There is loads more we can do … 40% of dementia worldwide is preventable by correcting modifiable risk factors like blood pressure.
 
‘[We could also offer] more rehabilitation services for people with dementia in the same way that we offer stroke rehabilitation.’
 
The World Health Organization has released 12 recommendations for reducing the risk of cognitive decline. The majority of these represent areas within the expertise of GPs, including being physically active, stopping smoking, eating a balanced diet, looking after your weight and managing hypertension, diabetes and cholesterol.
 
Importantly, GPs are also trained to manage the emotional and psychological impact dementia can have, with Dr Long reiterating that it can be an extremely sensitive issue requiring great skill and care from GPs.
 
‘There’s a lot of stigma and fear of dementia,’ she said.
 
‘We know that dementia is the second most feared condition in Australia and people are seeing it more on TV in famous people like Bruce Willis.
 
‘Fear can drive people not to engage so it’s important to work with our patients rather than blaming them, for example, for their weight or their diet.’
 
From a practical viewpoint, Dr Long encourages colleagues and the public to keep raising the profile of dementia in Australia.
 
In particular, she advocates for more awareness and aggressive preventive treatment in women, as dementia is the leading cause of death for women in Australia. She suggests that when women present to GPs for treatment of perimenopausal health issues, which can often include menopausal ‘brain fog’, brain health should become part of the conversation too.
 
‘There is definitely not enough awareness and awareness is crucial. We need to have these conversations with our patients,’ she said.
 
‘Women are twice as likely to get dementia and this is not just because they live longer. The research suggests there are other factors at play which we don’t yet fully understand.
 
‘We are very good at proactively treating blood pressure in men owed to a fear of males being at increased risk of heart disease. We should also be properly treating blood pressure in women in order to maintain brain health.’
 
Dr Long also reminds colleagues to utilise evidence-based free online screening tools such as the CogDrisk tool developed by UNSW, which is able to calculate what risk individuals over the age of 40 have of developing dementia at age 65. The free 20-minute self-assessment questionnaire can be completed by patients and then used in consultation with GPs to provide practical, individualised actions to lower dementia risk.
 
‘The tool allows me to ask patients “if there is anything on the list that you think you can do” or “anything that you’d like to do but could use a little help from me”,’ she said.
 
‘[Even] simple things like eating fish twice per week [can help].’
 
Dementia Australia encourages anyone with concerns to contact the National Dementia Helpline on 1800 100 500.
 
The Helpline is open 24-hours and available to anyone with questions about themselves, family or neighbours, not just health practitioners or consumers with an established diagnosis.
 
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