Single blood test could predict diabetes

日期:2019-03-02 09:17:12 作者:逄哌 阅读:

By Roxanne Khamsi The prospect of a cheap and reliable test to predict a person’s risk of diabetes has been raised by a new study. The research shows that high levels of a “retinol-binding” protein in a person’s body reveal an otherwise hidden condition known as insulin resistance, which precedes type 2 diabetes. “There is an incredibly high correlation,” says co-author Barbara Kahn at the Beth Israel Deaconess Medical Center in Boston, Massachusetts, US. In a person with type 2 diabetes, cells do not respond to insulin – a hormone that normally allows people to store blood sugar away. As a result, the blood sugar levels can skyrocket, with potentially fatal consequences. Doctors already know that overweight or obese people have a higher risk of developing type 2 diabetes. But lean people can also develop the condition – particularly in Asian countries – so it can be difficult to assess an individual’s risk of acquiring the illness. The best current method for measuring insulin resistance involves monitoring people as they receive injections of the sugar glucose – soaring glucose levels in the blood indicate resistance. But this test takes about 4 hours to conduct, and most hospitals are not equipped to conduct them on many patients, Kahn says. She adds that the currently available one-off measurements of insulin are unreliable. Kahn and colleagues have previously linked insulin resistance in rodents with high levels of retinol-binding protein 4 (RBP4), which is excreted by fat cells. Their new study examined 107 people in the US, Germany and Sweden. The volunteer group was a mix of lean and obese people with diabetes, pre-diabetes (a glucose intolerance linked to insulin resistance) or no diabetes. The team found that RBP4 levels revealed by blood tests closely matched the degree of insulin resistance found using the 4-hour glucose injection method. For example, 20 pre-diabetic people at one centre had RBP4 levels averaging 60 micrograms per millilitre of blood, while the 20 healthy controls averaged 26 micrograms per millilitre of blood. Lean individuals with a family history of type 2 diabetes also had higher levels of RBP4 than matched controls, hinting that the protein can indicate a predisposition to the illness regardless of weight. A test based on RBP4 may also one day help identify obese people who are at particular risk for diabetes. If these people failed to lose weight on an exercise regime, “it may come to a point where they would be put on an anti-diabetic as a preventative measure”, says Kahn. She adds that if future tests indicate that lowering RBP4 reduces the risk of diabetes, drugs could be developed to take advantage of this. “The approach would be to increase its excretion by the kidney,” Kahn says of the protein. Journal reference: New England Journal of Medicine (vol 354,