A groundbreaking tool which involves a finger-prick blood test and an online brain assessment has been created to estimate an individual’s risk of developing Alzheimer’s disease, according to new research.

The study, published in Nature Communications journal, involved 174 participants who carried out the self-administered test at home and posted their samples back to the research teams.

The finger-prick blood test measured biomarkers, p-tau217 and GFAP, which have been associated with Alzheimer’s disease and general brain decline.

Participants also completed online cognitive assessments.

Researchers found that combining the blood test with online brain tests can help identify a person’s likelihood of developing Alzheimer’s and then prioritise them for further testing, treatment and support.

Although dementia is often a difficult topic to discuss, understanding risk factors can help people make informed choices to potentially reduce their chances of developing the condition.

We spoke to Dr Richard Oakley, associate director of research and innovation at the Alzheimer’s Society, who outlined some key dementia risk factors everyone should know, and highlighted what lifestyle changes can help.

What are some risk factors that we can’t change?

Age

“Age is one of the biggest risk factors associated with Alzheimer’s because the chance of developing dementia increases as we age,” explains Oakley.

Above the age of 65, a person’s risk of developing Alzheimer’s doubles about every five years, according to Alzheimer’s Society’s website.

Part of this is due to natural changes in our body.

“One thing that we know leads to dementia is the build up of certain proteins, such as amyloid and tau, in our brains. Over time they aggregate together into these insoluble masses and start causing damage in our brains,” explains Oakley.

Sex

“The data shows us that women are more likely to get Alzheimer’s disease as they get older than men,” says Oakley.

According to Alzheimer’s Society, there are about twice as many women over 65 with Alzheimer’s as there are men over 65 with the condition.

However, Oakley says the reasons behind this are currently unclear.

“There are different theories around hormones and menopause that are being investigated, and lots of research is trying to work out exactly why this is so we can hopefully make changes to stop this,” says Oakley.

Genes

“There are genetic risk factors and certain mutations that people can have that can be passed down through families that can make you more predisposed to developing different forms of dementia such Alzheimer’s disease,” says Oakley.

Out of 10,00 people who have Alzheimer’s, less than 10 of those people will have it because of a familial gene, according to Alzheimer’s Society’s website.

There are also certain risk genes that increases a person’s chances of developing Alzheimer’s, such as the APOE gene.

“If you get two copies of APOE4 gene, a copy from your mum and another one from your dad, that significantly increases your chances of Alzheimer’s,” says Oakley.

“However, it’s important to emphasise that the APOE gene only increases a person’s chances of getting dementia and doesn’t cause the condition in everyone who has it.”

Certain health conditions

“One of the things that we know with Alzheimer’s disease is that it can become vascular, which happens when the damage in your brain is not only caused by certain proteins, but is also caused by a restriction of blood flow in and out of your brain,” explains Oakley.

“Therefore, things like high blood pressure, high cholesterol and conditions that affect your blood flow and metabolism such as diabetes, strokes and cardiovascular disease can all increase your risk of Alzheimer’s.”

Are there any lifestyle factors that can increase our risk of dementia?

“The 2024 Lancet Commission report on dementia prevention, intervention, and care showed that about 45% of all dementia cases are based on modifiable risk factors, rather than things like ageing and genes that we can’t change,” says Oakley.

The report found that addressing the following 14 health and lifestyle factors could prevent nearly half of global dementia cases:

– Quality of education in early life (5%)
– Social isolation (5%)
– Air pollution (3%)
– Traumatic brain injury (3%)
– Hearing loss (7%)
– Depression (3%)
– High blood pressure (2%)
– Type 2 diabetes (2%)
– Obesity (1%)
– Physical inactivity (2%)
– Smoking (2%)
– Excessive alcohol consumption (1%)
– Uncorrected vision loss (2%)
– High cholesterol (7%)

What lifestyle changes can we make to reduce our risk of Alzheimer’s disease?

“You can reduce your individual risk by doing things like quitting smoking, drinking alcohol only in moderation, having a healthy balanced diet, keeping a healthy weight and staying active,” says Oakley.

In addition, if you can keep your cardiovascular health under control, that can reduce your risk of developing dementia.

“We often say what’s good for your heart is good for your head, so controlling your cholesterol, and monitoring your blood pressure can make a big difference,” says Oakley.

Staying connected is also important.

“I would encourage people to carry on picking up hobbies and engaging with people,” advises Oakley.

“We also need to look out for our older loved ones and support them where we can to engage in hobbies and social interactions, because it does play a really important role, not only in general enjoyment, but also in reducing their risk of developing dementia.”