Blood test may predict who is most at risk for diabetes

Adding a test normally used for diabetes monitoring to employee wellness exams could identify people who don’t have the disease but are at high risk of developing it, a recent study suggests.

Researchers examined data from two different types of blood sugar test for more than 34,000 participants in a US employee wellness program who didn’t have diabetes. At the start of the study, they all also had fasting blood sugar in a healthy range.

Researchers also looked at results of blood tests showing so-called hemoglobin A1c levels, which reflect average blood sugar levels over about three months. Readings above 6.5 percent A1c signal diabetes, and none of the participants had readings this high.

But people who started the study with readings closest to a diabetes diagnosis – above 5.9 percent A1c but less than 6.5 percent - were more than eight times more likely to develop diabetes over about four years of follow-up than participants who had readings under 5.7 percent to begin with.

People who started out with A1c readings from 5.7 percent to 5.9 percent had about twice the risk of developing diabetes as people with lower results, researchers report in Diabetes Care.

“Identifying diabetes risk is really important because we know that type 2 diabetes can be prevented or delayed with effective intervention, including exercise and diet changes,” said Laura Rosella of the Dalla Lana School of Public Health at the University of Toronto.

“Employers would be interested in knowing who is at risk for diabetes so that they could potentially play a role in facilitating or offering preventive strategies that would prevent full blown diabetes,” Rosella said by email. “This keeps their employees healthy and prevents downstream health and disability care costs.”

Globally, about one in 10 adults has diabetes, according to the World Health Organization. Most have type 2 diabetes, which is associated with obesity and aging and occurs when the body can’t make or process enough of the hormone insulin.

Medications as well as lifestyle changes such as improved diet and exercise habits can help manage diabetes and keep symptoms in check. When diabetes isn’t well managed, however, dangerously high blood sugar can eventually lead to blindness, amputations, kidney failure, heart disease and stroke.

“One of the key issues with diabetes is that a person may make the transition from not having diabetes to having diabetes and not otherwise know it,” said Dr. Robert Cohen of the University of Cincinnati College of Medicine and the Cincinnati VA Medical Center.

That transition depends on an interaction between inherited factors and environmental factors and is still the subject of intense study, Cohen, who wasn’t involved in the study, said by email.

“One person can do a great job on all the environmental factors (lifestyle, diet, exercise, avoiding smoking) and still develop diabetes while another can do considerably less well yet not go on to diabetes - there is a lot of difference between people in how those factors interact,” Cohen added.

“Hence, we need a screening procedure to pick up the problem early,” Cohen said.

During the study, about 13 percent of the people with the highest A1c readings went on to develop diabetes, versus less than 1 percent of people with lower readings.

One limitation of the study is that researchers lacked data on whether any employee wellness programs were implemented to prevent diabetes in the people who appeared most at risk, and how effective they might have been. The study authors couldn’t be reached for comment.

“The obvious next step is an intervention study to test whether A1c screening in combination with employee wellness programs is a more cost-effective method of preventing diabetes than such programs alone,” said Mika Kivimaki, a researcher at University College London in the UK, who wasn’t involved in the study.

“Many employees with diabetes are not diagnosed and do not get treatment,” Kivimaki, who wasn’t involved in the study, said by email. “A1c screening could help to address this important problem.”