Endocrine Abstracts

Context: The influence of beta cell replacement on daily glucose profile in Type 1 diabetes mellitus (T1DM) is not firmly established.

Objective: To examine the influence of islet transplantation (IT) on the various component of dysglycemia in T1DM patients.

Design, setting and patients: Single arm open labeled study. Twenty-three consecutive patients with T1DM, 11 males and 12 females, 14 non uremic and 9 uremic with a previous kidney graft, receiving IT at a referral center from 2003 to 2007. All participants completed a 3-year follow-up.

Intervention: IT consisting of 2 or 3 intra-portal allogenic islet infusions over 3 months with the Edmonton immuno-suppression protocol.

Outcomes: Glucose daily profile was assessed during 72 hours by continuous glucose monitoring system (CGMS) prior to transplantation, at 6 months and yearly during 3 years after transplantation. Outcomes were mean glucose (MG), glucose standard deviation (GSD), the percentage of time spent in hyperglycemia >180 mg/dL (HYPER), and the percentage of time spent in hypoglycemia < 54 mg/dL (HYPO). Graft function was estimated with beta score, a previously validated index (range 0–8) based on insulin or oral treatment requirements, plasma C-peptide, blood glucose, and A1C. Analysis was per intention to treat.

Results: At 3 years, 19 patients had a functional graft and 10 remained insulin independent with A1c ≤6.5%. Median A1c in the whole cohort was 6.7% (interquartile range[IQR], 5.9%-7.7%) vs. 8.3% (IQR, 7.3%-9.0%) at baseline (P<0.01). The four CGMS outcomes were significantly improved vs. baseline (P<0.01), in a close relation with graft function (P<0.001). Partial function (beta score 3) was sufficient to abrogate HYPO but optimal function (beta score 8) was necessary to normalize MG, SD, and HYPER.

Conclusion: Glucose daily profile significantly improved during the 3-year period post-IT and reached normal values when optimal graft function was achieved.

Relation between graft function and the various outcomes of continuous glucose measurement during follow-up (a, mean glucose; b, glucose standard deviation; c, percentage of time with glucose >180 mg/dL; d, percentage of time with glucose <54 mg/dL). Tukey box plots indicates median interquartile range and upper and lower range. (P<0.0001; test for linear trend).

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This work was supported, however funding details unavailable.