Glucose Monitoring and Sensing

Abstract

Glucose monitoring is critical to enable people with diabetes to self-manage effectively, especially those with insulin-treated diabetes. Self-monitoring of capillary blood glucose (SMBG) has been available to people with diabetes for four decades and is now being supplemented and, for some, superseded by continuous glucose monitoring (CGM) provided by subcutaneously implanted sensors. Information such as estimated glucose concentrations, rate of change, alerts for impending glucose extremes and historical patterns can enable more appropriate carbohydrate intake, physical activity, insulin administration, and lifestyle decisions in real-time. Improvements in overall glycaemic control, as measured by HbA1c, time-in-range for glucose readings, hypoglycaemia exposure, and hypoglycaemic events, as well as quality of life, have all been reported with CGM. Flash glucose monitoring (FGM) with retrospective review of previously recorded continuous glucose readings from a subcutaneous glucose sensor is likely to be a replacement for SMBG. Sensor-augmented insulin pump therapy uses CGM data for feedback control of insulin delivery, and pumps with automatic low glucose-activated suspend of the basal insulin infusion are already in widespread clinical use and effective at reducing hypoglycaemia in type 1 diabetes. Hybrid closed-loop systems employing CGM are entering practice and fully closed-loop systems are under development.