Diabetes: Choosing and Using Your Glucose Meter (cont.)
Feelings about Fingersticks. Surprisingly, most of the participants stated that fingerstick discomfort was not a big concern - even with children: "At first, fingersticks were a real problem, but now it doesn't bother her."
Most participants stated that discomfort was an issue when they first started to use the meter; this was especially true for children, but that the discomfort grew less important after a few weeks or months of use.
However, one participant of a "fragile" child with diabetes stated: "We test 8 to 10 times a day. He was losing sensitivity in his fingertips [from the frequent fingersticks]. We prefer the meter that allows testing in alternative sites."
Use of Test Solution. Most users did not use test solution often. Some never used it. They stated that the solution was difficult to use because it expired in a month, it was difficult to order, and they were not convinced that it helped.
Important Features. Users discussed and rated aspects of meters such as accuracy, ease-of-use, cost of the meter, cost of test strips, size, whether it was recommended by a friend etc. The most important consideration in this group was accuracy. This was followed by "ease of use" and then affordability.
Sampling blood from alternative sites may be desirable, but it may have some limitations. Blood in the fingertips show changes in glucose levels more quickly than blood in other parts of the body. This means that alternative site test results may be different from fingertip test results not because of the meter's ability to test accurately, but because the actual glucose concentration can be different. FDA believes that further research is needed to better understand these differences in test values and their possible impact on the health of people with diabetes.
Glucose concentrations change rapidly after a meal, insulin or exercise. Glucose levels at the alternative site appear to change more slowly than in the fingertips. Because of this concern, FDA has now requested that manufacturers either show their device is not affected by differences between alternative site and fingertip blood samples during times of rapidly changing glucose, or alert users about possible different values at these times.
Recommended labeling precautions include these statements:
In October, 2001, FDA held a public meeting to discuss the types of information and labeling needed for glucose measuring devices if the blood sample is taken from alternative sites rather than the fingertip. Presenters included manufacturers of blood glucose meters, healthcare providers, people with diabetes, and parents of children with diabetes.
Minimally Invasive and Non-Invasive Glucose Meters
FDA has approved one "minimally invasive" meter and one "non-invasive" glucose meter. Neither of these should replace standard glucose testing. They are used to obtain additional glucose values between fingerstick tests. Both devices require daily calibration using standard fingerstick glucose measurements and both remain the subject of continuing studies to find how they are best used as tools for diabetes management.