Simple blood test may predict dementia risk before symptoms even appear

Age is the greatest known risk factor for dementia — though it seems to go beyond the number of candles on the birthday cake.

New research out of the UK reports that biological age, the age of our organs, tissues and cells, plays a major role in dementia risk.

“Our findings suggest that biological aging data can help identify individuals at risk of dementia before clinical symptoms emerge,” lead study author Julian Mutz of King’s College London said in a statement.

Over 6 million Americans have dementia, a progressive brain disorder that affects memory, language, problem solving and judgment.

Symptoms include forgetting names or recent events, expressing confusion about time and place and struggling with a daily routine.

A chronological age over 60, high blood pressure, diabetes, tobacco use, sedentary lifestyle, brain injury and family history of the disease generally raise the risk of dementia.

Without major intervention to curb unhealthy lifestyle choices, US dementia cases are expected to double by 2060 to nearly 1 million new cases annually.

For the study published Wednesday, Mutz’s team analyzed data from over 220,000 UK residents, including the nutrients and hormones in their blood (known as metabolites), their incidence of dementia and the age they started to experience symptoms.

Nearly 4,000 participants developed dementia during the study period. The researchers determined that those who had a higher biological age than chronological age were more likely to get a diagnosis.

A biological age can increase faster than a chronological one due to cellular damage from stress and poor habits and environmental factors like pollution and extreme heat.

The age difference link was more pronounced with regards to vascular dementia, which specifically affects thinking skills as the second most common form of dementia, after Alzheimer’s disease.

About 16% of participants had a 20% greater risk of dementia because they had an age gap greater than one standard deviation from the mean.

The risk was 60% greater for vascular dementia.

Those with older biological ages and two copies of APOE4, the strongest genetic risk factor for late-onset Alzheimer’s, were 10 times more likely to develop dementia.

The findings were published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association.

“By combining genetic factors with potentially modifiable factors captured in biological aging, we may be able to develop preventative strategies, potentially based on a simple blood test,” Mutz said.

Mutz hopes to spot dementia sooner and delay it or even stop it altogether. The key may be aging clocks based on metabolites.

Now, biological aging clocks are not new — they date back at least a decade. They’re constantly being refined as scientists and researchers debate which clock is the most accurate.

“As blood plasma-based clocks are scalable and minimally invasive,” Mutz said, “they could potentially be part of mid-life screening or used to help refine the selection of individuals to take part in research into prevention or disease-modifying trials for dementia.”