Cystic fibrosis-related diabetes before lung transplantation is associated with lower survival but does not affect long-term renal function

Objective: To describe the prevalence of cystic fibrosis-related diabetes (CFRD) before and after lung transplantation (LT); to analyse the survival and renal function after LT according to the CFRD status before LT.

Methods: Sixty cystic fibrosis (CF) patients transplanted at the Lyon University Hospital between 2004 and 2014 were included. Genotype, pancreatic status, age at LT, survival were recorded. Glucose tolerance status, daily insulin dose requirement, glomerular filtration rate (GFR), and daily glucocorticoid (GC) dose were recorded before LT and until December 2016.

Results: The median follow-up was 5.6 (3.8-8.2) years, and nine patients died. Survival was poorest for patients with CFRD before LT compared with those without CFRD (P = 0.03) but was not correlated with the GFR before LT, with sex, age at LT, or CF genotype. The prevalence of CFRD was 68% at 2 years and 54% at 5 years. For persistent insulin-treated CFRD, the insulin requirement decreased (-2.1 IU/d/y; P < 0.01) and was correlated with the daily GC dose (+0.4 IU/d for one additional milligram, P = 0.012). Seven (11%) patients who had insulin-treated CFRD before LT became nondiabetic after LT, with a median time of 2 (1-4) years. After LT, the GFR decreased (-5.3 ml/min/1.73 m ² /y; P < 0.001) and was not correlated with the CFRD status before LT.

Conclusions: CFRD before LT is associated with poor survival after LT, which should lead to better management of diabetes. Some patients with pre-LT CFRD became nondiabetic after LT. CFRD is not associated with renal insufficiency after LT.