CGM Shows Islet Transplantation Prevents Hypoglycemia, Correcting Time in Range and Reducing Glycemic Variability, Despite Subnormal Beta-Cell Function

Abstract

The impact of clinical islet transplant (CIT) on glycemic variability compared with type 1 diabetes (T1D) subjects and nondiabetic controls has not been explored. Aim: To evaluate the relationship between glycemic variability (by CGM) and islet graft function in CIT vs. T1D subjects on Continuous Subcutaneous Insulin Infusions (CSII), using healthy, nondiabetic subjects as reference. Methods: CIT recipients n=39, (insulin independent vs. dependent: n=15 vs. n=24) and subjects on CSII therapy (n=10) all with T1D were assessed at 1 year post-intervention with CGM. Published data from nondiabetic controls were used for comparison. Fasting glucose, C-peptide and HbA1c concentrations and insulin dose were recorded (including in a control cohort, n=28) where applicable; BETA-2 scores were calculated in those with endogenous C-peptide. Results: CIT recipients had decreased coefficient variation of glucose and lower time in hypoglycemia vs. those on CSII therapy; BETA-2 scores were ∼20% lower in CIT recipients vs. controls (p<0.05). Conclusion: Islet transplant recipients have diminished glycemic variability with abrogation of hypoglycemia vs. CSII at 1 year. Normalisation of time in range and glycemic variability was observed in insulin independent CIT recipients despite beta cell function ∼20% lower than in nondiabetic subjects. Disclosure S. Forbes: None. T. Olateju: None. A. Lam: None. J. Casey: None. J. Campbell: None. L. Reid: None. R.A. Oram: Other Relationship; Self; Randox. A.J. Malcolm: None. A. Shapiro: Consultant; Self; Viacyte, Inc., Protokinetix. P.A. Senior: Consultant; Self; Abbott, AstraZeneca. Research Support; Self; AstraZeneca, Prometic Life Sciences Inc., Novo Nordisk Inc., Sanofi. Consultant; Self; Eli Lilly and Company. Speaker's Bureau; Self; Eli Lilly and Company, Novo Nordisk Inc.. Consultant; Self; Novo Nordisk Inc., Janssen Pharmaceuticals, Inc.. Speaker's Bureau; Self; Janssen Pharmaceuticals, Inc.. Consultant; Self; Boehringer Ingelheim Pharmaceuticals, Inc.. Speaker's Bureau; Self; AstraZeneca, Merck & Co., Inc., Abbott. Research Support; Self; Viacyte, Inc..