Ketone bodies represent natural energy-rich molecules that are formed in the liver from fatty acids and serve as an alternative energy source to glucose when the body is deprived of food or on a low-carbohydrate diet. While elevated ketone levels are physiologic during exercise or ketogenic diet, pathologically high concentrations can lead to life-threatening diabetic ketoacidosis (DKA) in people with diabetes. DKA is one of the most serious acute complications in people with diabetes, especially in type 1 diabetes (T1D). Main underlying causes are insulin deficiency due to missed injections, pump catheter occlusions or infections. Despite modern diabetes technologies, DKA prevention remains an unresolved challenge. Continuous ketone monitoring (CKM) may offer promising solutions. In current practice, adequate ketone measurements for early detection of DKA are frequently insufficient. CKM, ideally as a Dual Glucose Ketone sensor (DGK), could close this gap in clinical care. The system continuously measures ketone levels and automatically raises an alarm when critical levels are reached - without any active intervention by the patient. This may be of utmost benefit for people with T1D in situations that carry the risk of insulin deficiency, those with repeated episodes of DKA, pregnant women with T1D, children and adolescents with T1D and people on SGLT-2 inhibitor therapy. An initial CKM prototype demonstrated its feasibility in principle back in 2021, and a DGK will soon be available. Clinical studies on patient-relevant endpoints - in particular on the actual reduction of DKA episodes through CKM - are still pending. The available data mainly originate from feasibility studies and pilot studies under controlled conditions; international expert committees identify open questions for important research priorities. At the conceptual and pathophysiological level, the technology shows plausible potential to gain new scientific and clinically relevant insights into the physiology and pathophysiology of ketone and for improving the safety of diabetes therapy - however, clinical evidence must be provided in controlled studies with clinical endpoints.
As a long-term indicator of glucose control quality, HbA( 1c) testing has become an established part of diabetes treatment. A comparison of a glucose parameter calculated using continuous glucose monitoring (CGM), i.e., the glucose management indicator (GMI), and laboratory-measured HbA( 1c) values shows a relatively good agreement in many people with diabetes, but in some cases also significant discrepancies. The difference between the two glycemic indices is >0.8% or 9 mmol/mol HbA( 1c) in approximately 10% of patients. Such differences are clinically relevant as they influence decisions about changes in therapy. It is therefore important to clarify the possible causes of these differences: On the one hand, the GMI values calculated from CGM values may be incorrect (e.g., problems with the quality of glucose measurement of the CGM system, interference with other substances/medications, or inflammation in the area where the sensor is inserted into the skin). On the other hand, HbA( 1c )measurements do not always adequately reflect the level of glycemia, which can be falsely low or falsely high due to various factors. This recommendation aims to propose a course of action in the event of such discrepancies in order to find a possible mistake, thus to correctly assess the glycemic status of the individual with diabetes.
