Low-Dose Thymoglobulin Use in Elderly Renal Transplant Recipients Is Safe and Effective Induction Therapy

Abstract

Current immunosuppressive therapies and protocols have led to significant improvements in early patient and graft survival rates following kidney transplantation. Whether induction therapies such as rabbit anti-thymocyte globulin (rATG) contribute to these improved results remains controversial. Full-dose rATG induction therapy (7–10 mg/kg) has been associated with increased morbidity, which may be especially true in a high-risk population such as the elderly. Therefore, we studied the efficacy and tolerability of a low-dose rATG induction strategy in 45 older recipients (>65 years) compared to 45 concurrently transplanted younger patients (<65 years). Both groups received a similar low-dose of rATG induction therapy (older: 2.96 ± 1.29 vs younger: 3.2 ± 2.11 mg/kg). All patients were maintained on a calcineurin inhibitor, mycophenolic acid, and low-dose prednisone (5 mg/d). To date, none of the older patients experienced acute rejection, whereas one younger patient had an acute rejection episode. Initial hospital stays were equal (older: 7.8 ± 3.2 vs younger: 7.5 ± 4.4 days, P = .35). Within the first 6 months, nine older patients required rehospitalization compared to 15 younger patients ( P = .15). Bacterial infections in older and younger recipients were equal including wound (4 vs 0), urine (20 vs 15), lung (1 vs 1), and skin (0 vs 2), respectively. There were two BK viral infections in older patients, whereas there were three viral infections, two cytomegalovirus cases, and one Herpes zoster case in younger patients. Calculated 6-month glomerular filtration rate was equal in both groups (older: 55.7 ± 18.5 vs younger: 52.7 ± 18.5 mL/min). Three-year patient and graft survival rates were equivalent for older and younger patients (86.6% vs 97.6%, respectively). In conclusion, low-dose rATG induction therapy is safe and effective in patients older than 65. When compared to younger patients, low-dose rATG leads to equivalent graft survival and function without incurring excess morbidity in the older population.