 |
 |
 |
|
 |
FDA Home Page | Search
FDA Site | FDA A-Z Index | Contact
FDA | FDA Centennial
| Email this Page To a Friend |
 |
By Carol Rados
Glucose meters help people with diabetes check their blood sugar. And because diabetes that is not well-controlled can lead to complications such as blindness, these medical devices must be reliable, accurate, and easy to use and understand.
Recent problems reported to the Food and Drug Administration indicate that some people who use certain blood glucose meters may have problems properly setting the units of measurement on their meters or may inadvertently switch them. Also, in some cases, jarring or dropping the meter can cause the units to switch without the user being aware. These actions can lead to misinterpretation of glucose test results and to dosage errors in insulin or in oral diabetes medication.
Diabetes is a disease in which the body does not produce or properly use insulin. Insulin is a hormone that is needed to convert sugar, starches, and other food into energy needed for daily life. According to the American Diabetes Association, about 20 million people in the United States, or 7 percent of the population, have the condition.
The problem meters are designed to report blood glucose levels in two different measurements--the U.S. standard--milligrams per deciliter (mg/dL)--and the standard used in Europe and elsewhere--millimoles per liter (mmol/L). The normal fasting blood sugar (glucose) for people who don't have diabetes is usually less than 100 mg/dL or less than 5.5 mmol/L. The conversion factor between the two units of measure is 18, meaning a value in mg/dL equals 18 times the comparable value in mmol/L.
According to reports, users have accidentally changed one unit of measure to the other while setting their meter's date and time, or while changing the battery. There also have been reports of the unit of measure changing after a meter was jarred or dropped.
"Someone who is familiar with their meter is going to realize if it is displaying the wrong unit of measure," says Tama Antonia Donaldson, director of public affairs at Abbott Diabetes Care in Alameda, Calif. Reports, however, indicate that in some cases, even those who are familiar with their meters have not realized the wrong measurement unit that is being displayed. Donaldson advises, "Users should verify that their meter displays the correct unit of measure each time they test."
Checking blood glucose is a critical step in managing diabetes, says Joanna K. Zawadzki, M.D., in the FDA's Division of Metabolism and Endocrinology Products. Frequent testing and good recordkeeping give people the most accurate picture of diabetes control.
However, she says, "As with any tool, a glucose meter has to be used correctly for it to be most effective." Blood glucose meters measure the amount of glucose in the blood and serve as an aid in monitoring the effectiveness of diabetes management at home or in a clinical setting. Glucose control can help prevent serious complications of diabetes, such as kidney failure, blindness, and amputations.
To date, at least three companies have reported this problem. It appears that companies making meters with the ability to report in both units of measure need to consider this problem in the design and labeling of their product.
Manufacturers are not instructing users to return their meters. Instead, the firms have issued worldwide notifications to all health care professionals and users, when known, about the problem. In addition to verifying the correct unit of measure and code number each time, Zawadzki adds, "Patients should take the time to review their glucose meters with their diabetes health care providers and read the information that accompanies the device."
As an added safety measure, Donaldson says that new models of meters have the correct unit of measure locked in place.
For information on how to change a unit of measurement for meter readings, users should refer to their owner's manual or should contact the manufacturer directly. People who think they may have been using the wrong readout on their meters for a long period of time, and who are now worried about their health, should contact their doctors immediately.
The FDA's MedWatch Program
www.fda.gov/medwatch/
(800) 332-1088