Do pretransplant C‐peptide levels predict outcomes following simultaneous pancreas‐kidney transplantation? A matched case‐control study

Abstract

Following simultaneous pancreas-kidney transplantation (SPKT), survival outcomes are reported as equivalent in patients with detectable pretransplant C-peptide levels (Cp+) and a "type 2″ diabetes mellitus (DM) phenotype compared to type 1 (Cp negative [Cp-]) DM. We retrospectively compared 46 Cp+ patients pretransplant (≥2.0 ng/mL, mean 5.4 ng/mL) to 46 Cp-(level < 0.5 ng/mL) case controls matched for recipient age, gender, race, and transplant date. Early outcomes were comparable. Actual 5-year patient survival (91% versus 94%), kidney graft survival (69% versus 86%, p = .15), and pancreas graft survival (60% versus 86%, p = .03) rates were lower in Cp+ versus Cp-patients, respectively. The Cp+ group had more pancreas graft failures due to insulin resistance (13% Cp+ versus 0% Cp-, p = .026) or rejection (17% Cp+ versus 6.5% Cp-, p = .2). Post-transplant weight gain > 5 kg occurred in 72% of Cp+ versus 26% of Cp-patients (p = .0001). In patients with functioning grafts, mean one-year post-transplant HbA1c levels (5.0 Cp+ versus 5.2% Cp-) were comparable, whereas Cp levels were higher in Cp+ patients (5.0 Cp+ versus 2.6 ng/mL Cp-). In this matched case-control study, outcomes were inferior in Cp+ compared to Cp-patients following SPKT, with post-transplant weight gain, insulin resistance, and rejection as potential mitigating factors.

Higher Fasting Pretransplant C-peptide Levels in Type 2 Diabetics Undergoing Simultaneous Pancreas-kidney Transplantation Are Associated With Posttransplant Pancreatic Graft Dysfunction

“…Yet some have claimed the C-peptide level may not matter much. 20 There are little data to support decision-making related to this clinical question. In this cohort of 76 SPK recipients with T2DM, we analyzed our outcomes in different ways.…”

Influence of donor and recipient sex on outcomes following simultaneous pancreas–kidney transplantation in the new millennium: Single‐center experience and review of the literature

“…Contraindications to SPKT at our center included age >65 years; insufficient cardiovascular reserve; current substance abuse; active infection or recent malignancy; major ongoing psychiatric illness, recent noncompliance, or lack of adequate social support; significant obesity (body mass index [BMI] >32 kg/m 2 ); severe vascular disease; or inability to either understand or commit to the more intense follow‐up associated with SPKT compared to kidney transplantation alone. Selection criteria for SPKT in patients with a type 2 diabetes phenotype included patients <65 years of age, insulin‐requiring for a minimum of 3 years with a total daily insulin requirement <1 u/kg/day, a fasting C‐peptide level <12 ng/ml, absence of severe vascular disease or tobacco abuse, adequate cardiac function, and presence of “complicated” or hyperlabile diabetes 22,24 . For purposes of this study, type 2 diabetes was defined as having a pretransplant C‐peptide level ≥2.0 ng/ml ( n = 50).…”

“…Selection criteria for SPKT in patients with a type 2 diabetes phenotype included patients <65 years of age, insulin‐requiring for a minimum of 3 years with a total daily insulin requirement <1 u/kg/day, a fasting C‐peptide level <12 ng/ml, absence of severe vascular disease or tobacco abuse, adequate cardiac function, and presence of “complicated” or hyperlabile diabetes. 22 , 24 For purposes of this study, type 2 diabetes was defined as having a pretransplant C‐peptide level ≥2.0 ng/ml ( n = 50).…”

“…General indications for SPKT were insulin-requiring diabetes with complications and the predicted ability to tolerate the operative procedure, manage the requisite immunosuppression, and manage the need for close follow-up post-SPKT irrespective of chronologic age or C-peptide production. [19][20][21][22][23] 22,24 For purposes of this study, type 2 diabetes was defined as having a pretransplant C-peptide level ≥2.0 ng/ml (n = 50).…”

Simultaneous Pancreas-kidney Transplantation Candidates With Type 2 Diabetes Mellitus: Elevated C-peptide Levels Warrant Scrutiny, May Portend Worse Outcomes

“…9 The group from Wake Forest also recently updated their experience reporting that C-peptide positive patients had significantly worse 5-y pancreas graft survival, which was attributed to posttransplant weight gain, insulin resistance, and rejection. 10 Here, Parajuli et al specifically evaluate pretransplant fasting C-peptide level and subsequent graft function in T2DM patients who underwent SPK, identifying several important concepts. Recipients were defined as T2DM according to a previously reported scoring system and were stratified according to their pretransplant fasting C-peptide as either low (<2 ng/mL), medium (2-8 ng/mL), or high (>8 ng/mL).…”