Quick facts: Clinical research, 752 individuals with type 2 diabetes, quantitative study, DNA methylation as a way to identify epigenetic biomarkers in blood.
People with type 2 diabetes are up to four times more likely to have heart attacks, strokes, anginas and other coronary heart diseases than healthy people. Therefore, biomarkers that help us understand which individuals are at risk of being affected are needed.
A research team led from Lund University in Sweden, followed 752 people who, when the study started, were newly diagnosed with type 2 diabetes. None of the participants, who came from the diabetes cohort ANDIS (All New Diabetics in Skåne), had previously had any major cardiovascular diseases. The researchers followed the participants' cardiovascular health for just over seven years, during which time 102 of them suffered serious cardiovascular complications.
"By studying chemical changes in the participants' genome – so-called DNA methylation – we wanted to find epigenetic biomarkers that predict cardiovascular disease. DNA methylation controls which genes are active or turned off in our cells, and when it does not work properly, it can contribute to the development of cardiovascular disease", says Charlotte Ling, Professor of Diabetes research at Lund University.
The researchers found more than 400 sites with altered DNA methylation in blood and 87 of these were used to develop a score scale that can assess an individual's risk of developing serious cardiovascular complications.
"We could say with a 96 percent probability whether someone was not at risk of developing cardiovascular disease. The negative prediction value was thus very strong. Since the follow-up of the participants of just over seven years is relatively short, we need to follow them longer in order to probably also get a stronger positive prediction value – that is, how great the probability is that a person will actually get a macrovascular event", says Sonia García-Calzón, researcher at the University of Navarre, Pamplona.
People with type 2 diabetes who are found to be at risk of developing cardiovascular disease can thus get quick help with preventive measures regarding diet, physical activity and weight management. They may also get more help to improve their blood sugar control and receive treatments that protect their heart and blood vessels.
"Healthcare today uses clinical variables such as age, gender, blood pressure, smoking, harmful cholesterol, long-term blood sugar and kidney function to estimate the risk of future cardiovascular disease, but it is a rather blunt tool. If you add DNA methylation, you have a much better measure of a future risk. We therefore want to develop a kit for clinical use, so that a simple blood sample can measure DNA methylation and predict who is at risk of becoming ill using the scoring scale", concludes Charlotte Ling.
