People could slow down effects of ageing if they spot warning signs of decline in middle age, study shows

During middle age, the brain undergoes significant molecular, cellular, and structural changes. Many of these have been linked to cognitive decline, which has also been shown to accelerate during middle age. Picture: AP /David Duprey

Middle-aged people could slow down or even reverse the effects of ageing if they could spot warning signs of decline likely to come in their 60s and 70s, according to a new study.

Researchers say while middle-aged people are as likely to suffer cognitive decline as older people, they stand a much better chance of being less affected if they get themselves treated.

They should, in time, be able to do this by taking a simple blood test to find certain so-called “markers” in blood associated with various age-related processes.

The researchers accept while there is some evidence exercise might aid healthy cognitive ageing, more research is needed.

But University College Cork researcher Sebastian Dohm-Hansen said: “A lot of what is good about healthy lifestyle choices like exercise is that it, too, can spread via the blood and slow down the ticking of the clock [or even reverse it].

“By looking for common but opposing effects of ageing and exercise, we may be able to find new interventions to help us enjoy good health for longer."

The team he helped lead reviewed past evidence from human and animal studies.

This was used to illustrate that during middle age, the brain undergoes significant molecular, cellular, and structural changes.

Many of these have been linked to cognitive decline, which has also been shown to accelerate during middle age.

The review, published in the journal Trends in Neurosciences on Tuesday, says middle age is associated with changes in the volume of several brain structures.

It is also associated with shrinking of the hippocampus — the part of the brain that involves memory and learning — and decreased connectivity between different parts of the brain.

Mr Dohm-Hansen said: “In your 40s and 50s, the brain undergoes accelerating change, especially in its ‘wiring’ and communication between cells. This particularly seems to affect everyday memory but also simpler things like reaction time.

During middle age, the review highlights, the composition of your blood changes rapidly, and some of these changes in your 40s can predict future cognitive decline 20 years later in your 60s. 

"The fourth and fifth decades of life may be a turning point in the organisation of brain networks, characterised by optimal efficiency, system segregation and modularity, followed by accelerated decay of these properties."

He said most studies of brain health and cognitive decline focus on older age groups, but by this time, interventions may have limited efficacy.

However, he added screening for risk of future cognitive decline could help by allowing treatment to begin earlier, when it might be more effective.

He added: “A better understanding of brain shifts during middle age might also help identify novel targets for therapy. The science of ageing has long overlooked middle age.

“This is because the effects of time are most easily seen in old age. But at that point, the time for intervention is quickly running out. Middle age is associated with specific and modifiable risk factors for future dementia risk.”

The report was co-authored by neuroscientist Professor Yvonne Nolan of APC Microbiome Ireland, a Science Foundation Ireland research centre based at UCC.

This research was supported by the Science Foundation Ireland, the Irish Health Research Board and Alzheimer Nederland. Separate research is under way to produce a blood test that could predict conditions such as Alzheimer's.