Background: Pancreas and islet transplantation can achieve optimal glycemic control in patients type 1 diabetes (T1DM) and persistent problematic hypoglycemia. We describe our experience with these two therapies over a 20-yr period.

Methods: Patients with T1DM undergoing pancreas (PT) or islet (IT) allotransplantation from January 1st 1999 to May 1st 2019 were included. Univariate analyses were done using X2 tests and Student’s t tests for categorical and continuous variables, respectively.

Results: We include 413 patients with a mean duration of T1DM of 30.6 yr (SD 10.8), 272 (65.9%) underwent IT and 141 (34.1%) PT. Mean follow-up was 7.4 yr (SD 5.2). More female patients (55.9% vs. 34.0%, p<0.001), and an older age at transplant were observed in the IT group (48.4 yr vs. 41.0 yr, p<0.001) compared to PT. Baseline mean glycated hemoglobin (HbA1c) was 8.4% (SD 1.2) which decreased to 6.6 (SD 0.8) and 5.6 (SD 0.7) in the IT and PT groups over the following 3 months after transplant, respectively. HbA1c remained lower as compared to baseline values up to 15 yr after transplant in both groups (7.3 [SD 1.4) in IT and 6.1 [SD 0.8) in PT, p=0.01 for both). Insulin independence rates were lower in the IT group vs. the PT group (77.2% vs. 95.0%, p<0.001), as well as the percentage of follow-up time off-insulin (46.6% [SD 31.2] vs. 92.3% [SD 18.5], p<0.001). However, the mean number of hospital admissions was lower in IT patients (1.2 [SD 0.7] vs. 1.7 [SD 1.2], p=0.009), similarly to 1-yr mortality rates (0.0% vs. 3.6%, p=0.002); mortality rates were equivalent thereafter.

Discussion: PT provides better glycemic control than IT. However, caveats including higher early mortality rates and greater long-term morbidity should be thoroughly discussed with patients. This study provides robust information to guide evidence-informed practice and establish more realistic expectations for both physicians and patients involved the care of IT and PT patients.


B.A. Marfil-Garza: None. A. Lam: None. D. Bigam: None. P. Senior: Research Support; Self; Allergan, Novo Nordisk. A. Shapiro: Consultant; Self; Viacyte, Inc.

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