A panel of diabetes experts created a method for users of Abbott FreeStyle Libre CGM systems, which are among the newest CGM systems on the market. The approach helps FreeStyle Libre users leverage trend arrows for insulin dose adjustments and improve their blood glucose control. More than one million people worldwide use these systems, according to Abbott.
The method is detailed in a new article published in the Journal of the Endocrine Society .
CGM systems measure glucose levels in the fluid between the body’s cells every few minutes throughout the day and night. The technology can tell the user whether glucose levels are rising or falling, and monitor trends from the past several hours. The Endocrine Society recommends CGM systems as the gold standard for managing type 1 diabetes, and the technology also can be useful for people with type 2 diabetes.
To avoid dangerous complications, it is important for people with diabetes to keep their blood sugar in a targeted range. Over time, uncontrolled high blood glucose levels can lead to heart disease, stroke, kidney failure, blindness and nerve damage. When blood glucose levels drop too low, individuals are at risk of losing consciousness, experiencing seizures or even dying.
The Abbott FreeStyle Libre CGM systems display trend arrows to indicate when a user’s glucose levels are rising or falling and how quickly those changes are occurring. The information is designed to help users anticipate where glucose levels will be in the future, but there is little guidance to help CGM users incorporate this information into insulin dose calculations.
“Our method fills the gap by suggesting strategies that healthcare providers and CGM users can use to refine insulin doses using trend arrows in the FreeStyle Libre CGM systems,” said the article’s first author, Yogish C. Kudva, M.B.B.S., of the Mayo Clinic in Rochester, Minn. “We want to make it easier for CGM users to act on the trend arrow information."
The manuscript also offers recommendations for how to use the unique features of the systems and trend arrows in specific situations, including after a meal, prior to physical activity, and when the user is ill.
Society experts developed similar methods for Dexcom G5 CGM users – both adults and children – last year. The new method is based on that approach, but it is tailored to address the unique features of Abbott FreeStyle Libre CGM systems.
The method provides tables with suggested insulin dose adjustments in insulin units to simplify calculations for CGM users. The approach can be used by any individual with diabetes who is on intensive insulin therapy. The tables were developed based on an individual’s insulin sensitivity. In other words, the lower the sensitivity to insulin, the greater the recommended dose adjustment. The information applies to both FreeStyle Libre system and FreeStyle Libre 14 day system, which can be worn for up to two weeks consecutively to avoid the need for painful fingersticks.
Previous approaches to using the trend arrows often required complex calculations or relied on insulin bolus calculators, which was of limited use to CGM users using insulin pens or insulin vials who can only adjust their insulin doses in pre-defined increments. The Society sought to streamline the process and make it applicable for people with a wide range of insulin sensitivities, regardless of how their insulin is delivered.