Long-term outlook for renal transplant recipients with one-year function. "Doctor, what are my chances"?

ABSTRACT

Patients with renal transplants that survive the first year often ask about the chance of long-term function. We studied 1850 patients with primary transplants from June 7, 1963 to September 1, 1988 who had graft survival of greater than 1 year. Patients were grouped by donor type, diabetic status, and whether or not they received cyclosporine (CsA). Half-life (T1/2) was used to compare long-term survival rates. We determined the long-term graft survival inclusive and exclusive of death with function (DwF) in order to study all patients and to direct attention to immunologic losses. Pre-CsA, DwF was the major cause of graft loss in each cohort. Cause of DwF was cardiovascular (49%), infection (26%), and cancer (14%). The percentage of patients experiencing DwF was much higher in the pre-CsA group vs. the CsA group HLA-identical living related donor, 16% vs. 3%; non-HLA-identical LRD, 22% vs. 5%; and cadaver donors, 26% vs. 11%. T1/2 for 711 transplants to diabetics (DM) was 9.01 +/- .54 years, while for transplants to 1139 nondiabetics (NDM) T1/2 was 13.57 +/- .68 (P less than .05). When DwF is excluded (DwFex) DM T1/2 = 23.5 +/- 2.69 and NDM T1/2 = 22.2 +/- 1.55 (NS). Overall, for HLA-identical transplants (n = 297) T1/2 = 26.13 +/- 3.35 and DwFex T1/2 = 104.3 +/- 28.93. Nonidentical LRD (n = 845) T1/2 = 11.25 +/- .61 and DwFex T1/2 = 19.37 +/- 1.55. For CAD (n = 701) T1/2 = 9.10 +/- .54 and DwFex T1/2 = 17.49 +/- 1.65. Comparing pre- and post-CsA cohorts, CsA has not resulted in significant improvement in long-term graft survival by T1/2 analysis with DwFex. It appears that overall long-term graft survival has improved with the introduction of CsA. Much of the improvement may be attributed to better first year graft survival and a reduction in cases of DwF. DM patients have an equal opportunity for long-term graft survival if they do not die from other causes. Excluding DwF, especially as an older population is transplanted, is important in determining chances of immunologic loss. Use of this type of analysis suggests that long-term outlook for 1-year graft survivors is excellent.