The combined effect of pre-transplant triglyceride levels and the type of calcineurin inhibitor in predicting the risk of new onset diabetes after renal transplantation.

BACKGROUND: Insulin resistance precedes overt diabetes in the general population and hypertriglyceridemia is a reliable marker of the disorder. Thus, patients in the waiting list with hypertriglyceridemia may be at risk for new-onset diabetes after transplantation (NODAT). Objectives. We investigate whether pre-transplant triglyceride (TG) levels are a risk factor for NODAT and whether they exert a combined effect with the type of calcineurin inhibitor (CNI).
METHODS: We analysed 314 consecutive non-diabetic recipients [215 cyclosporine A (CsA); 99 tacrolimus (Tacro)] transplanted between 1999 and 2003 with a mean follow-up of 34 months. Outcome was NODAT defined by ADA criteria.
RESULTS: NODAT developed in 81 recipients (25.8%). Multivariate analysis which included a propensity score for factors determining CNI allocation showed that age (OR: 1.06; 95% CI: 1.03-1.09), pre-transplant BMI (OR: 1.1; 95% CI: 1.02-1.17),TG levels (OR: 1.3 per 50 mg/dl increment, 95% CI: 1.07-1.6) and treated acute rejection (OR: 4.8, 95% CI: 3-11), but not the type of CNI, were independent risk factors for NODAT. A significant interaction between pre-transplant TG and type of CNI was observed. Using CsA as the reference, the combination of Tacro plus pre-transplant hypertriglyceridemia (>/=200 mg/dl) showed an OR of 3.26 (1.4-7.8) to develop NODAT, contrasting with an OR of 0.75 (0.34-1.6) in Tacro recipients with pre-transplant TG levels <200 mg/dl.
CONCLUSION: Pre-transplant hypertriglyceridemia was a risk factor for NODAT only in recipients treated with Tacro; it highlights the importance of pre-transplant insulin resistance in the pathogenesis of NODAT.