Objectives: The number of elderly kidney transplant recipients is increasing, and age-tailored induction immunosuppression regimens are needed. We compared safety and efficacy of basiliximab versus thymoglobulin at various dosages.
Materials and methods: Of 590 kidney transplants at our center from 2012 to 2019, 119 (20.1%) were for recipients over 65 years of age; 118 patients received deceased donor kidneys, and 1 received a related living donor kidney. We retrospectively reviewed medical records for demographics, baseline characteristics, donor characteristics, induction regimens, infectious complications, graft function, and patient survival.
Results: Patients were subdivided into the following 4 induction immunosuppression groups: basiliximab (n = 15, 12.6%), 3 mg/kg thymoglobulin (n = 8, 6.7%), 4.5 mg/kg thymoglobulin (n = 67, 56.3%), and 6 mg/kg thymoglobulin (n = 29, 24.4%). All patients received pulse doses of methylprednisolone followed by a prednisone taper. Other maintenance immunosuppression agents included tacrolimus and mycophenolic acid. Recipients in the basiliximab and 3 mg/kg thymoglobulin groups were older (median age ⟩70 years; P ⟨ .001). The 4.5 and 6 mg/kg thymoglobulin groups had higher proportions of African American patients and patients with calculated panel reactive antibody over 20%. There were significantly fewer infectious complications in the basiliximab and 3 mg/kg thymoglobulin groups. Despite differences in biopsy-proven acute rejection rates, estimated glomerular filtration rate and graft and patient survival rates at 1 year were similar across groups. All patients with biopsy-proven acute rejection were African American patients.
Conclusions: Kidney transplant in patients ≥65 years is safe and feasible. Changes in this unique population's immune system warrant age-tailored regimens. We found that patients at low immunologic risk would benefit from basiliximab orthymoglobulin at 3 mg/kg. Regardless of calculated panel reactive antibodies, African American patients should be considered as high immunologic risk group forrejection, and higher thymoglobulin dosing should be considered.