Risk factors of chronic rejection in renal transplantation, results of a monocentric study.

Chronic rejection remains the single most important cause of renal allograf t loss after the first year post-transplant. We per formed a matched case c ontrol study within our cohort of 471 renal allograft recipients, comparing 66 patients with histologically proven chronic rejection with 66 controls. Analysis of immunological (transfusion, sensitisation, HLA matching, numbe r of transplantation, number of acute rejections (AR), immunosuppression) a nd non-immunological (donors and recipients age and sex, CMV disease, post- transplant acute tubular necrosis, cold ischemia) factors which could predi ct the occurrence of chronic rejection (CR) was performed, using Wilcoxon r ank test, Mac Nemar test and Cox model. Univariate analysis showed that potential risk factors for CR are. donor ag e > 45 years (p = 0.05), recipient age < 40 years (p = 0.008), CMV disease (p = 0.03), number of acute rejection episodes (p = 0.009), retransplantati on (p = 0.002). Multi-Variate analysis showed that only the following facto rs significantly increased the risk of CR: AR episodes (p = 0.01) with an o dds-ratio at 3.5 (95% Cl = 1.3-3.9) for the second acute rejection episode and at 6.5 (95% Cl = 1.5-29.4) for the third acute rejection episode, donor age > 45 years (p = 0.03) with an odds-ratio at 3.5 (95% Cl = 1.1-10.6). O ur data suggest that better matching at donor recipient age and more potent immunosuppressive protocols resulting in no acute rejection may improve th e long term graft survival. They also show that the use of old donors it 45 years), as a response to organ shortage is detrimental for long term renal function.