Blood Sugar Monitoring: Progress Reported on Non-invasive Glucose Monitoring Systems
New Continuous Glucose Monitoring System Approved for Doctors' Use;
Second Device — GlucoWatch — Reported to Be Effective in Clinical Trials
BOSTON — June, 1999 — The government has approved MiniMed Inc.'s "continuous glucose monitoring system" for doctors to use occasionally to help adjust patients' treatment — but the product will not replace finger prick blood tests that patients perform regularly to monitor their blood sugars.
Positive results for clinical trials studying another non-invasive product, the GlucoWatch, were reported this summer at the American Diabetes Association Scientific Sessions in San Diego.
The MiniMed product, available early in the year 2000, but only by prescription, uses a sensor implanted just under a diabetes patient's skin on the abdomen for up to three days. The sensor will record glucose levels every five minutes. A computer program then downloads the records to the doctor, so that the doctor can analyze the three days of daily blood sugar fluctuations and make recommendations for improving the patient's pattern of eating, medication administration and exercise to improve blood sugar control.
The product is an important first step toward the development of a continous glucose monitor that people with diabetes could wear and refer to whenever necessary to get an accurate reading of what their blood sugar is at any given minute. The MiniMed product, however, does not provide on-demand blood sugar level results, but instead provides the data to be downloaded into a computer in a doctor's office after several days.
Patients use traditional blood sugar monitoring equipment to know what their blood sugars are at any given time during the day, so they can make adjustments in their eating, exercise and medication to keep blood sugars in as normal a range as possible.
The Food and Drug Administration (FDA), in approving the MiniMed technology, notes that "continuous tissue glucose monitoring is a breakthrough technology that could revolutionize the care of diabetics. This new system is a first step in that direction."
Another device, still in clinical trials and not yet approved by the FDA, enables users to check their glucose levels at about 20-minute intervals throughout the day — without doing anything once they put it on and without feeling anything other than a tingling sensation, reported Satish K. Garg, MD, director of the adult diabetes program at the University of Colorado Health Science Center in Denver at this year's American Diabetes Association scientific meetings in June in San Diego.
This device, called a GlucoWatch®, uses a process that involves applying a small electric current to the skin — using a AAA battery — whenever glucose levels are to be measured.
The Colorado study of the GlucoWatch involved 39 individuals with diabetes (average age 31) who had had diabetes for an average of 18 years. All had extensive experience with self-monitoring of blood glucose. Each wore two of the devices on their forearm. (They must be placed with the sensor on the middle of the inner arm, at least three inches away from the wrist or elbow joint, to avoid excess hair or movement). Participants compared results of the GlucoWatch with test results they got using conventional blood glucose monitoring equipment tests.
"This study confirmed the utility of the GlucoWatch," said Dr. Garg. "Results showed that it gave glucose values that were nearly identical to those obtained using the two blood glucose monitors."
The GlucoWatch product still must be approved by the Food and Drug Administration and is not likely to be commercially available for a year or more. More information on these types of devices will be available on this Web site when the information becomes available.
