Poor long-term outcome in second kidney transplantation: a delayed event

Area of Science:

• Nephrology
• Transplantation Immunology
• Clinical Epidemiology

Background:

• Historical data suggested poorer outcomes for second transplant recipients (STR) versus first transplant recipients (FTR), often attributed to confounding factors.
• Recent studies using advanced statistical methods have questioned this established notion, leaving the prognosis for STR a subject of ongoing debate.

Purpose of the Study:

• To evaluate and compare long-term patient and graft survival rates between second transplant recipients (STR) and first transplant recipients (FTR).
• To analyze the incidence of acute rejection episodes (ARE) in both STR and FTR groups.

Main Methods:

• An observational study utilized data from the French DIVAT prospective cohort (1996-2010), including 3103 patients (641 STR).
• Maintenance immunosuppression involved calcineurin inhibitors (CNI), mTOR inhibitors, or belatacept, alongside steroids and mycophenolate mofetil.
• Cox regression models, adjusted for confounding variables like pre-transplant anti-HLA immunization, were used to analyze survival and ARE.

Main Results:

• STR demonstrated a significantly higher risk of graft failure compared to FTR (Hazard Ratio = 2.18, p = 0.0013), with this increased risk becoming apparent several years post-transplant.
• No significant differences were observed between STR and FTR in the overall occurrence of acute rejection episodes (ARE) (HR = 1.01, p = 0.9675) or steroid-resistant ARE (HR = 1.27, p = 0.4087).

Conclusions:

• The elevated risk of graft failure in second transplantation persists even after adjusting for confounding factors, contrasting with first transplantation outcomes.
• Discrepancies in literature regarding STR outcomes may stem from the infrequent use of time-dependent statistical modeling.
• Clinical decisions should differentiate between first and second transplant recipients due to distinct long-term graft survival probabilities.