Use of continuous glucose monitoring as an educational tool for lifestyle modification in a patient with newly diagnosed type 2 diabetes treated without insulin

Continuous glucose monitoring (CGM) has become standard for patients with all types of diabetes undergoing intensive insulin therapy.¹ According to the American Diabetes Association’s recommendations,² CGM should be considered for individuals with diabetes who use any insulin therapy for daily management. However, the use of CGM should also be considered in adults with type 2 diabetes (T2D) receiving glucose-lowering medications other than insulin to help achieve and maintain individualized glycemic goals.

A 43-year-old man was referred from a general practitioner to a diabetology department due to new-onset diabetes. Blood glucose level measured using a home glucose monitoring device was 500 mg/dl (reference range [RR], 80–140 mg/dl). On admission, the patient reported polyuria, polydipsia, and an 8-kilogram weight loss over about 1 month. On physical examination, his general condition was good; height and weight were 187 cm and 106 kg, respectively. His body mass index was 30.3 kg/m², indicating class I obesity. Glycated hemoglobin (HbA_1c) concentration was 13.6% (RR <⁠5.7%). A differential diagnosis for diabetes was performed: C-peptide level was 1.2 ng/ml (RR, 1.2–3.6 ng/ml), and autoantibodies against glutamic acid decarboxylase were negative. Additionally, the patient had hyperlipidemia. Based on clinical characteristics, a diagnosis of T2D was established. During hospitalization, initial intravenous insulin infusion was administered, followed by intensive insulin therapy with multiple daily injections. The next step involved starting noninsulin medications: metformin, dapagliflozin, and dulaglutide. On discharge, the patient was on 2000 mg of metformin, 10 mg of dapagliflozin, 1.5 mg of dulaglutide, and 10 units of neutral protamine Hagedorn insulin. He was educated about diet, physical activity, and self-monitoring blood glucose with a glucometer. He continued outpatient diabetes care, with the first visit scheduled 3 months after hospitalization. Due to good glycemic control (HbA_1c, 7.5%), basal insulin was discontinued. However, as a professional truck driver, the patient reported difficulties with using the glucometer regularly. Therefore, a CGM system (FreeStyle Libre 2, Abbott, Abbott Park, Illinois, United States) was introduced for 28 days. The patient’s ambulatory glucose profile is shown in Figure 1A, with mean glycemia of 122 mg/dl and the coefficient of variation of 17.5%. After 1 month, an in-depth interview was conducted. The patient reported feeling better; he was able to manage his diet, plan his meals, and learn how to prepare new dishes (Figure 1B). Additionally, he mentioned that CGM helped him in his daily routines when he forgot to measure his blood sugar with a traditional glucometer. He found CGM more convenient and easier to use than a glucometer. The patient also discovered that brisk walks helped him manage blood glucose levels. In the long term, he felt that CGM provided a sense of security. However, after a month, he decided not to continue with CGM due to a lack of reimbursement.

This clinical image illustrates a potential educational value of CGM in patients with newly diagnosed T2D treated without insulin therapy.³ Randomized controlled trials involving individuals with uncontrolled T2D on noninsulin therapy, who used intermittent short-term real-time CGM, report a significant reduction in HbA_1c levels.⁴ Additionally, CGM-guided feedback has been shown to support lifestyle modification by helping patients understand the relationship between diet, physical activity, and glucose levels.⁵ These data suggest that patients should be able to choose their preferred glycemic control methods.