Flash Glucose Monitoring and Diabetes Mellitus Induced by Immune Checkpoint Inhibitors: An Approach to Clinical Practice

Abstract

Objectives. The aim of this study is to investigate in depth diabetes mellitus associated with immune checkpoint inhibitors (DM-ICIs) by analysing a case series. We also evaluated the clinical impact of flash glucose monitoring (FGM) systems in the management of this entity. Methods. We conducted an observational cohort study of DM-ICIs diagnosed in two hospitals in Seville (Spain). Patients with a new diagnosis of diabetes mellitus (DM) or with sudden worsening of preexisting DM after starting treatment with ICIs, with a random 5 hour-postprandial C-peptide value of 250 mg/dL of 10.2%. The mean time below range (TBR) 54-69 mg/dL was 2%, while the mean TBR250 mg/dL (16.3% to 7.7%, p=0.09), mean TBR 54-69 mg/dL (5.2% to 2%, p=0.16), and mean TBR<54 mg/dL (1.8% to 0.2%, p=0.31), along with an increase in mean values of TIR 70-180 mg/dL (46.5% to 60.5%, p=0.09). The lack of statistical significance in the differences observed in the mean FGM values over the follow-up period may be related to the small sample size. Conclusion. DM-ICI is recognised by a state of sudden-onset insulinopenia, often associated with DKA. The use of FGM systems may be a valid option for the effective management of DM-ICIs and for the prevention of severe hyperglycaemic and hypoglycaemic episodes in this condition.