SummaryIn this ancillary study of the CONCEPT trial, we studied the role of CsA withdrawal at 3 months (3M) post-transplant on the intensity of epithelial phenotypic changes (EPC, an early marker for kidney fibrogenesis) on the 12M surveillance biopsy. Although conversion from CsA to sirolimus (SRL) at 3M was reported to have improved mean graft function at 12M, it did not reduce the score of EPC (1.73 AE 1.15 in the SRL group vs. 1.87 AE 1 in the CsA group, P = 0.61). Acute rejection, which had occurred twice more frequently in SRL-converted patients included here, was associated with 12M EPC. Interestingly, we observed that the patients durably exposed to CsA and who developed 12M EPC had a significant progression of blood pulse pressure (pp) from 1 to 6M post-transplantation (Dpp = +12.3 mmHg, P = 0.0035). Pulse pressure at 4, 6, and 9M and pp progression from 1 to 6M were significantly associated with the development of EPC at 12M in renal grafts. Logistic regression analysis revealed that a high 6M pp (≥60 mmHg) was an independent risk factor for 12M EPC with an odds ratio of 2.25 per additional 10 mmHg pp (95%CI: 1.14-4.4, P = 0.02) after adjustment with recipient's and donor's age, acute rejection incidence and immunosuppressive regimen. A post hoc analysis of the data collected in the whole population CONCEPT study revealed that pp was significantly higher at 6 months in patients maintained on CsA and that at this time point pp correlated negatively with GFR at 1 year.
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