A recent study has shown that organs age at different rates, with an ageing immune system being tied to dementia and Alzheimer’s.

The study, which was published in the Lancet Health journal, has examined certain proteins found in people’s organs to show that our body parts can age at different rates.

Professor Luke O’Neill told the Show Me The Science podcast that examining the physical age of a person’s individual organs can also predict the likelihood of that person developing certain diseases.

“So, the bottom line from this first part was they noticed in some people the organs are ageing more quickly,” he said.

“They looked at nine organs – kidneys, pancreas, blood vessels, liver, lungs, heart, the immune system, the intestines and the brain, and across those nine organs then they could age them in people.

“Very importantly then, they had the health records of these people in their seventies - the key bottom line [is that] people with heart disease in their 70s, when they were 55, their heart was older than the average.

“So, in other words, the heart was under pressure, perhaps had aged more quickly, and that predisposed them then to having heart disease later.”

Prof O’Neill said this was significant as these individuals had shown no other clinical evidence of having heart disease in their 50s.

Cardiology consultation. Image: RayArt Graphics / Alamy. 20 January 2012

“The one that really stood out was dementia, they were expecting to see markers of brain ageing,” he said.

“So, for example, if you’re in your mid-fifties and your brain is a 70-year-old's brain, over time then that turns into dementia – but it wasn’t in the brain, it was in the immune system.

“One big headline is a more rapidly ageing immune system is a risk factor for developing dementia and Alzheimer’s in this situation.”

According to Prof O’Neill, this supports evidence that Alzheimer’s could be an immune disease.

Health advice

This could also give people an insight on how to best focus on their health as they age.

“Blood tests – because remember, it’s all in the blood, which is tremendous – may advise whether a person needs to take better care of a particular organ and potentially provide an early warning signal that they may be at risk of a particular disease,” he said.

“You might have a situation where you go to a GP, the GP takes a blood sample and will measure hundreds of proteins in that blood sample.

“The data then – using AI probably – will spit out the following information, that you’ve got a heart that’s ageing a bit too quickly, you better do something about it, or you have an immune system that’s beginning to age too quickly.”

Prof O’Neill said this would allow people to seek treatments or make lifestyle adjustments that could delay the progression of these diseases.

Main image: Luke O'Neill (L) and a person getting blood taken (R).