Endocrine Abstracts

Risk factors involved in new-onset diabetes mellitus after transplantation (NODAT) remain unclear. Clinical studies have demonstrated the association between low vitamin D levels with insulin resistance and diabetes. In animal models, osteocalcin deficiency leads to high glucose levels and insulin resistance.

The aim of this study is to evaluate the prevalence of NODAT and other alterations of glucose metabolism after liver transplantation (LT) at our institution. Also, we assess the relationship between serum osteocalcin, 25-OH vitamin D levels and NODAT. Influence of hepatitis C virus (HCV) infection was also studied.

Methods: In the period 2011–2012, 133 LT patients (90 men and 43 women) with a mean age of 58.8 years were studied. None of them had been diagnosed of diabetes prior to transplant. Minimum period posttransplantation was 6 months and mean follow-up was 9.2 years. 75 g oral glucose tolerance test (OGTT) was performed to assess glucose, insulin and C-peptide levels at baseline, and 60 and 120 min. Data on medical history, anthropometric measurements and lab test (including HbA1c, total osteocalcin, and 25-OH vitamin D levels) were collected.

Insulin resistance (HOMA-IR) and insulin sensitivity (QUICKI) indexes were calculated. 2011 ADA diagnostic criteria were used.

Results: Thirty four patients developed diabetes or were treated with insulin or oral antidiabetic medication. OGTT was performed in 99 patients: 12.1% had NODAT criteria, and 32.3% showed impaired glucose tolerance (IGT). 30.3% showed vitamin D deficiency (<20 ng/ml). No significant differences were observed in osteocalcin and vitamin D levels between NODAT, IGT, and normal. No correlation was found between osteocalcin and glucose, insulin, C-peptide, or HbA1c. HOMA-IR was significantly higher in diabetic (P<0.001) than in normals. QUICKI was significantly lower in prediabetic (P<0.05) and diabetic (P<0.001) compared with normal. HCV positive status (before and after transplantation) was associated with diabetes onset (P=0.05 and 0.001 respectively.

Conclusion: Prevalence of NODAT and IGT is high in LT recipients. Our study didn’t find osteocalcin and vitamin D levels as predisposing factors for the onset of both conditions. Hepatitis C virus infection increased the risk of NODAT.