 One of the most worrisome complications of type 2 diabetes is an increased likelihood of heart disease. In fact, cardiovascular dysfunction often starts even before high blood sugar becomes apparent. Catching this breakdown early could improve the use of protective therapies, but most available detection methods are expensive, invasive, or difficult to perform. Now, a research team based in Singapore has come up with a better way. By noninvasively tracking blood flow in the radial artery, a small blood vessel located in the wrist, they successfully predicted heart disease risk in patients with diabetes. Blood flow depends on endothelial cells, specialized cells that line the blood vessels. When these cells are healthy, vessels readily expand and contract as the heart beats, leveling out blood pressure. One of the earliest signs of heart disease is endothelial dysfunction, which causes blood vessels to lose their distensibility and grow stiff. To examine the connection between diabetes and endothelial dysfunction, the researchers compared changes in distensibility in patients with diabetes and healthy volunteers. They accomplished this by using a method known as magnetic blood pulse measurement. The method relies on the fact that a healthy artery is continuously expanding and contracting as iron-rich blood is pumped through the vessel. If a magnet is placed over the artery, the increase in blood volume and thus iron content that occurs during vessel expansion is sufficient to disrupt the magnetic field. This disruption can be measured using special sensors. An artery that's become stiff won't readily expand to fill with blood and doesn't create the same amount of magnetic disturbance compared to healthy vessels. The researchers tracked these magnetic changes to calculate the Radial Artery Maximum Distensibility Index, or RA-MDI, which they then used to predict cardiovascular risk. The results showed that the patients with diabetes has significantly higher RA-MDI scores than the healthy volunteers. The team compared these scores against other measures of cardiovascular risk, including various clinical parameters, carotid ultrasonography, and blood tests. They found that the RA-MDI score identified high-risk patients, just as well as these more traditional means. Although the work must still be replicated in a larger cohort of patients, these preliminary results suggest that measuring RA-MDI offers a way to accurately identify the start of vascular disease earlier, less invasively, and with greater technical ease than other methods.