Advances in Continuous Glucose Monitoring Systems for Diabetes Management – Review of the Most Common Systems in Poland

Diabetes mellitus is an increasing health problem worldwide. The management of diabetes involves regular monitoring of blood glucose levels. Traditionally, this has been achieved through self-monitoring of blood glucose using fingersticks and a glucose meter. However, this method can be inconvenient and painful for the patient. Therefore, there has been a push towards developing new techniques for measuring glycemia. The latest methods of glycemic control have gone beyond the standard assessment of HbA1c, and thanks to the introduction of sensors for continuous glycemic monitoring, the time in range parameter (TIR) comes to the fore in the assessment of glycemic control.[1] Recently, continuous glucose monitoring technology has seen a significant increase in the accuracy of the systems. Most current systems available to patients have a MARD (mean absolute relative difference) < 10%, which is a significant difference from the systems of 20 years ago, which had an MARD of more than 20%.[2] This allows for much better control and more detailed insight into the patient's daily glycemia and cooperation of the continuous glycemia monitoring system with an insulin pump (hybrid closed-loop systems). In Poland, the most common monitoring systems stand out: FreeStyle Libre 2 (FSL2), created by Abbott Diabetes Care, is a modern glucose monitoring system. It is designed to provide continuous glucose monitoring for individuals with diabetes, offering an alternative to the traditional method of self-monitoring of blood glucose (SMBG).[3,4] In terms of efficacy, the FSL2 system has been evaluated in several clinical trials and real-world studies. For instance, the REPLACE randomized controlled trial (RCT) provided pivotal efficacy data for patients with type 2 diabetes (T2D) receiving insulin therapy. By using the FreeStyle Libre 2 system, compared to the traditional method of measuring blood glucose using a glucometer, patients experienced fewer episodes and shortened the duration of hypoglycemia. Subsequent studies have also proven a significant impact on reducing HbA1c levels in patients using the FreeStyle Libre 2 system.[3] In a study on the accuracy of the system, from 144 adults and 129 pediatric participants, MARD was 9.2% and 9.7% for FreeStyle Libre 2.[5] The Dexcom G6 is a continuous glucose monitoring (CGM) system developed by Dexcom. It is designed to provide real-time, dynamic glucose information every 5 min, allowing individuals with diabetes to see their glucose levels. For the Dexcom G6 system, studies have also proven a positive effect on reducing HbA1c levels and the frequency and intensity of hypoglycemia episodes. Additionally, it has been proven that the use of the Dexcom G6 system is associated with changes in patient behavior resulting from continuous insight into glycemia measurements, which contribute to the improvement of blood glucose levels.[6] In a study involving 218 patients reported an overall Mean Absolute Relative Difference (MARD) of 12.8%.[6] There is also the new Dexcom ONE+. It is the latest continuous glucose monitoring (CGM) system from Dexcom. The Dexcom ONE+ is Dexcom's most accurate sensor to date. It provides real-time glucose level data 24 h a day to a smartphone or receiver. The Eversense system developed by Senseonics includes a small sensor that is inserted under the skin. It is a long-term, implantable CGM system. Sensor readings come from the interstitial fluid and send the data to a mobile device for display. The system provides glucose readings every five minutes, allowing users to see their current glucose levels, trends, and alerts. In the PROMISE study, the Eversense CGM system had an overall MARD of 9.1%.[7] All three systems have been proven to improve quality of life by reducing the number of hypoglycemia and hyperglycemia incidents, lowering HbA1c levels, and improving time in range. It's important to note that while these figures provide a general idea of the accuracy of each system, individual experiences may vary. Therefore, the best system would be the one that best fits the user's lifestyle, comfort, and specific diabetes management needs. In conclusion, the evolution of diabetes technologies, particularly CGMs, has significantly improved the quality of life for individuals with diabetes. With the continuing development of technology, the methods of treating diabetes in the future will also evolve and become more and more advanced and better in terms of accuracy and reliability. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest.