New Continuous Glucose Monitor Eliminates Routine Fingersticks
For decades, people with diabetes have been asking when they would be able to routinely test their sugar (glucose) levels without having to prick their fingers. On September 27, 2017, the Food and Drug Administration approved an answer: the FreeStyle Libre, which is the first wearable flash glucose monitoring system that eliminates the need for routine fingersticks.
The challenge of diabetes
In 2015, 30.3 million Americans (9.4% of the population) were living with diabetes. This included 23.1 million diagnosed and 7.2 million undiagnosed cases. Overall, nearly half of people with diabetes don’t test themselves on a regular basis. Yet routine monitoring of blood glucose levels is critical because the health risks associated with unmanaged blood sugar are great. For example:
- Low blood sugar (hypoglycemia), which can be accompanied by lightheadedness, anxiety, heart palpitations, dizziness, weakness, fatigue, headache, confusion, excessive sweating, and irritability, among other symptoms
- Complications associated with long-term poorly managed disease, such as diabetic neuropathy, kidney disease, development of cataracts, peripheral artery disease, heart attack, and stroke
New continuous glucose monitor
During a phone interview on December 13, 2017, endocrinologist Dr. Maria Tulpan, who is affiliated with Lenox Hill Hospital in New York City, called the new monitoring system “quite unique” and “revolutionary.” One reason for this description is that the device allows patients to immediately see the impact of their food choices and exercise on their sugar levels so they can make changes in their behavior.
“Patients do love it,” she said. “They like to get immediate feedback. Patients feel more in control.” Cher Pastore, a Certified Diabetes Educator, echoed the sentiments, noting that the new monitor is a great tool for helping patients modify their behavior in a very short time.
“We’ve seen in about a week patients are responding to what they’re seeing” on their device. For example, if patients notice their sugar is high, they examine what they are eating and make different decisions next time. “Patients have an immediate sense of what’s working, what isn’t working,” said Cher. “I think it gives them a sense of empowerment.”
How the new continuous glucose monitor works
The new glucose monitoring system is intended for people 18 years and older with diabetes and consists of two components: a sensor that is placed on the back of the upper arm, and a small hand-held scanning device. The sensor is about the size of two stacked quarters, adheres to the skin like an adhesive bandage, and is painless. After a 12-hour start-up period, patients can wear the sensor for up to 10 days. After that time they remove their sensor (like taking off an adhesive bandage) and place a new one on their arm. The sensor is water resistant and can be worn while bathing, swimming, or exercising.
To use the hand-held scanner, patients simply pass it over the sensor (within 1 cm to 4 cm) to get a reading, even through clothing, any time of the day or night. The sensor easily fits into a pocket or purse.
Even among individuals with diabetes who do conduct routine fingersticks, it is easy to miss significant fluctuations in sugar levels because each reading is simply a snapshot. Use of the new monitoring system not only allows patients to get an accurate reading of their glucose level; it also displays an arrow next to the reading that helps patients track trends. That is, it shows them which direction their blood glucose levels are going.
For example, Cher explained that patients with a blood sugar of 100 and an arrow going across the screen could feel secure since the arrow indicates a slow change. However, those with an arrow pointing down would know their levels were dropping quickly, which would be a call to action to take glucose and head off hypoglycemia. Thus, use of the new monitor can help patients stay in a much tighter range for their blood glucose and therefore help avoid hypoglycemia and other diabetic complications.
Caveats and cost
Other available continuous glucose monitors on the market can give a falsely elevated reading if the patient has taken acetaminophen; not so with the new meter. Dr. Tulpan noted there is “no interference we are aware of” when using the new scanner. The manufacturer (Abbott Laboratories) does warn users that “Fingersticks are required for treatment decisions when you see Check Blood Glucose symbol, when symptoms do not match system readings, when you suspect readings may be inaccurate, or when you experience symptoms that may be due to high or low blood glucose.” However, Dr. Tulpan noted that fingersticks are needed in “rare occasions.”
When it comes to cost, Dr. Tulpan noted that it is “much more affordable” than the other continuous glucose devices on the market. The cost of the scanner and the sensors is about $200 per month, and it hopefully will be covered by insurance plans.
For more information about FreeStyle Libre, patients should talk to their doctor and visit the Abbott Laboratories website.
Abbott Laboratories. FreeStyle Libre
American Diabetes Association. Statistics about diabetes
Food and Drug Administration. FDA approves first continuous glucose monitoring system for adults not requiring blood sample calibration. 2017 Sep 27
Interview with endocrinologist Dr. Maria Tulpan and certified diabetes educator Cher Pastore on December 13, 2017