London: A team of European researchers has developed a new test that can accurately measure biological ageing in a clinical setting.
The new test is an epigenetic clock — a type of biochemical assessment that looks at DNA to understand how well the body is ageing in contrast to its chronological age — and is the first of these cutting-edge tests to be proven to perform accurately in a clinical setting, in both healthy and unhealthy tissue.
Epigenetic clocks have been proposed as a ‘gold standard’ for measuring age accurately, beyond a person’s biological age, as they are able to measure methylation tags on DNA.
The clock — named the Glasgow-Karolinska Clock — developed by teams from University of Glasgow in the UK and the Karolinska Institutet in Sweden, while studying patients for the ageing effects of chronic kidney disease and related treatments.
“This study is the first time in a clinical setting that we can accurately report on the extent of biological as opposed to chronological ageing in chronic kidney disease patients,” said lead author Professor Paul Shiels, from the University of Glasgow.
“Our findings, using the new Glasgow-Karolinska Clock — show that not only are these patients ageing faster than people in the general population, their accelerated ageing only slows down once they have had a transplant. Treatment with dialysis does not appear to impact this process,” he added.
In the study, published in the Journal of Internal Medicine, the team studied more than 400 patients with chronic kidney disease in Sweden alongside around 100 matched population controls, to better understand the impact on ageing of the disease, including during dialysis treatment and after kidney transplant.
The team used the clocks to measure the change in biological age of around 47 patients one year after kidney transplantation, or one year after the start of their dialysis treatment, as well as how the healthy tissue in 48 controls aged by comparison.
The results showed that for patients with chronic kidney disease, their biological clock is ticking faster than the average person’s. This continues to be the case even after dialysis treatment. Indeed, patients’ biological clocks were only shown to slow down following a kidney transplant.
However, while the epigenetic clocks all showed a similar picture, the research team found that none of the current clocks could be shown to be accurate in a clinical setting, and all were found to be inaccurate to differing degrees when tested in healthy tissue over time.
The team’s Glasgow-Karolinska Clock that works on healthy and unhealthy tissue addressed this.
The results from this new clock matched what doctors saw in patients with chronic kidney disease, and also appeared to accurately assess healthy tissue too. This study is the first real-world test of epigenetic clocks in a normal ageing setting, and against clinical parameters.
As the body ages, a series of factors lead to epigenetic changes and loss of a chemical tag (DNA methylation) from your DNA. This is often associated with a range of diseases common to ageing, such as chronic kidney disease, cancer and heart disease.