Continuous Glucose Monitoring
What is continuous glucose monitoring?
Continuous glucose monitoring (CGM) systems use a tiny sensor inserted under the skin to check glucose levels in tissue fluid. The sensor stays in place for several days to a week and then must be replaced. A transmitter sends information about glucose levels via radio waves from the sensor to a pagerlike wireless monitor. The user must check blood samples with a glucose meter to program the devices. Because currently approved CGM devices are not as accurate and reliable as standard blood glucose meters, users should confirm glucose levels with a meter before making a change in treatment.
CGM systems are more expensive than conventional glucose monitoring, but they may enable better glucose control. CGM devices produced by Abbott, DexCom, and Medtronic have been approved by the U.S. Food and Drug Administration (FDA) and are available by prescription. These devices provide real-time measurements of glucose levels, with glucose levels displayed at 5-minute or 1-minute intervals. Users can set alarms to alert them when glucose levels are too low or too high. Special software is available to download data from the devices to a computer for tracking and analysis of patterns and trends, and the systems can display trend graphs on the monitor screen.
Additional CGM devices are being developed and tested. To learn more about such monitors and new products after approval, call the FDA at 1-888-INFO-FDA (463-6332) or check the FDA's website section titled "Glucose Meters & Diabetes Management" at www.fda.gov/diabetes/glucose.html [Editor's note: Dead link as of 02Dec2011].
What are the prospects for an artificial pancreas?
To overcome the limitations of current insulin therapy, researchers have long sought to link glucose monitoring and insulin delivery by developing an artificial pancreas. An artificial pancreas is a system that will mimic, as closely as possible, the way a healthy pancreas detects changes in blood glucose levels and responds automatically to secrete appropriate amounts of insulin. Although not a cure, an artificial pancreas has the potential to significantly improve diabetes care and management and to reduce the burden of monitoring and managing blood glucose.
An artificial pancreas based on mechanical devices requires at least three components:
With recent technological advances, the first steps have been taken toward closing the loop. The first pairing of a CGM system with an insulin pump-the MiniMed Paradigm REAL-Time System-is not an artificial pancreas, but it does represent the first step in joining glucose monitoring and insulin delivery systems using the most advanced technology available.
Points to Remember
Hope through Research
The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) and the National Institutes of Health (NIH) have encouraged and supported research that has helped researchers explore and develop improved glucose sensing technologies. NIDDK support was instrumental in the development of two CGM devices. One device is on the market and the other is under review by the FDA. Research supported by the NIDDK and NIH is contributing to the development of an artificial pancreas that will combine continuous glucose sensing with insulin delivery in a "closed-loop" system.
Participants in clinical trials can play a more active role in their own health care, gain access to new research treatments before they are widely available, and help others by contributing to medical research. For information about current studies, visit www.ClinicalTrials.gov.
For More Information
National Diabetes Information Clearinghouse
The National Diabetes Information Clearinghouse (NDIC) is a service of the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). The NIDDK is part of the National Institutes of Health of the U.S. Department of Health and Human Services. Established in 1978, the Clearinghouse provides information about diabetes to people with diabetes and to their families, health care professionals, and the public. The NDIC answers inquiries, develops and distributes publications, and works closely with professional and patient organizations and Government agencies to coordinate resources about diabetes.
Publications produced by the Clearinghouse are carefully reviewed by both NIDDK scientists and outside experts. This fact sheet was reviewed by William V. Tamborlane, M.D., Yale University.
This publication is not copyrighted. The Clearinghouse encourages users of this publication to duplicate and distribute as many copies as desired.
NIH Publication No. 09-4551