Under-the-Skin Blood Sugar Monitor Boosts Diabetes Control

Sept. 8 -- MONDAY, Sept. 8 (HealthDay News) -- A device worn under the skin that measures blood sugar 24/7 can benefit people with type 1 diabetes, a new study shows.

"Continuous glucose monitoring" consists of a disposable blood sugar sensor placed under the skin, worn for a few days and then replaced. The sensor sends data to a transmitter which, in turn, sends it to a receiver worn like a pager. The receiver displays blood glucose levels on a continuous basis.

The device used in the study "monitors blood glucose about every five minutes," said lead researcher Dr. Roy W. Beck, from the Jaeb Center for Health Research in Tampa, Fla. "We evaluated how much benefit, if any, that could have on control of diabetes in both children and adults with type 1 diabetes," he said.

Type 1 diabetes, often called juvenile diabetes, occurs when the body doesn't produce enough insulin. It affects about 5 percent of all diabetics. Type 2 diabetes, the much more common form, is typically brought on by excess weight or other metabolic imbalances.

Beck has a personal reason for being concerned about type 1 diabetes.

"I have a son who has type 1 diabetes who has used continuous glucose monitoring for two years now every day, except for a few days when it was in for repair, during which time he felt a great loss at not having it. There are many others like him. He was not part of the study," he said

In the study, the researchers found that adults gained substantially better control of their diabetes when using continuous glucose monitoring versus a group using conventional, intermittent blood sugar management.

Improved diabetes control was determined by using what is called the hemoglobin A1c test, which measures how effective blood sugar control is over three months, Beck explained.

"In addition, we were able to get better and tighter control -- closer to normal -- of blood sugar without dangerously low blood sugar levels," Beck said.

The report, funded by the Juvenile Diabetes Research Foundation, was published in the Sept. 8 online edition of the New England Journal of Medicine. It was also expected to be presented Monday at a meeting of the European Association for the Study of Diabetes, in Rome.

For the study, Beck's team randomly assigned 322 adults and children with type I diabetes to one of four brands of continuous blood sugar monitors, or home monitoring with a standard blood glucose meter.

Over 26 weeks, the researchers found that, for patients 25 years of age and older, continuous blood sugar monitoring showed significant improvements in blood sugar control.

For patients 15 to 24 years old, the difference between the groups was not significant, primarily because the younger patients were less likely to use the equipment continuously, the researchers found.

Among patients 25 years of age and older, continuous blood sugar monitoring was used by 83 percent of participants for six days or more per week. For younger patients, only 30 percent of those 15 to 24 used continuous monitoring, as did 50 percent of those aged 8 to 14.

Greater compliance with glucose monitoring among the younger patients comes with parental involvement, Beck said.

"Getting better control of diabetes using continuous glucose monitoring is almost certainly likely to equate with fewer long-term complications," he noted. "This will have substantial long-term benefit on quality of life and reduce health care costs," Beck said.

Based on these findings, he believes that continuous blood sugar monitoring should become a normal practice for type 1 diabetics and that insurance companies should start paying for the device.

Continuous glucose monitoring among people with type 2 diabetes has not yet been tested, Beck said. However, for type 2 diabetics who rely on insulin it may prove beneficial, he added.

Dr. Stuart Weiss, an endocrinologist at New York University Medical Center and a clinical assistant professor at NYU School of Medicine, New York City, believes the technology will eventually be used by all diabetics.

"As someone who has been using continuous glucose monitoring for a long time, I think it's wonderful that studies are coming out to support its use," Weiss said. "It really is a great tool," he said.

For people with type 2 diabetes, continuous glucose monitoring can be helpful, Weiss said. It especially helps patients understand which foods significantly alter their blood sugar, he said.

"If you don't test, you don't know," Weiss said. "The more you test, the more you know."

More information

For more about diabetes, visit the American Diabetes Association.

SOURCES: Roy W. Beck, M.D., Ph.D., Jaeb Center for Health Research, Tampa, Fla.; Stuart Weiss, M.D., endocrinologist, New York University Medical Center, and clinical assistant professor, NYU School of Medicine, New York City; Sept. 8, 2008, New England Journal of Medicine