Kidney Transplant Outcomes in Adolescents

The most common end-stage organ disease in children and adolescents is renal failure. The 10-year survival for adolescent-onset end-stage renal disease is 80%. It has been shown in previous studies that compared with younger recipients, adolescents have better graft survival at 1 year, but greater graft losses within 10 years of transplant.

According to researchers, there is a lack of evidence describing the risks of graft failure among renal transplant recipients stratified by age at the time of transplant. Previous studies have used various arbitrary age groupings with, the researchers noted, “differing results.” They added that, because the transition from pediatric to adult healthcare is a vulnerable period, “we need to better understand the factors affecting the health of kidney transplant recipients during this transition.”

The current study was a retrospective analysis of 168,809 first kidney-only transplant events from October 1987 through October 2010 in recipients up to 55 years of age [JAMA Intern Med. 2013;173(6):1524-1532]. The objective of the analysis was to determine the age at which renal transplant recipients are at greatest risk for graft loss. Data were gathered from the Organ Procurement and Transplantation Network Standard Transplant Analysis and Research database.

The researchers used a risk factor modeling approach to determine which covariates to add to the Cox proportional hazard regression model. They included only the covariates that acted either as a confounder or as an effect modifier.

Of the 168,809 first kidney-only transplants evaluated, there were 46,854 graft failures prior to patient death (27.8%) and 17,826 deaths with a functioning graft (10.6%), for a total of 46,854 death-censored graft failures and 64,680 non–death-censored graft failures. During the follow-up period, 15.2% of the recipients died, and 69.3% had a functioning graft at the time of death.

There were 2 variables that had significant interaction with age at transplant: (1) donor type (living vs deceased donor); and (2) the recipient’s type of insurance at the time of transplant (private vs government). From these 2 variables, the researchers constructed 4 unique groups: (1) living donor-government insurance, 21.0%; (2) living donor-private insurance, 22.1%; (3) deceased donor-government insurance, 44.8%; and (4) deceased donor-private insurance, 12.1%.

The highest risk of graft loss was found in adolescent recipients 14 to 16 years of age, starting at 1 year after transplant, and amplifying at years 3, 5, and 10 after transplant, despite this group having the best patient survival.

Black adolescents are at a disproportionate risk of graft failure at these time points compared with nonblack adolescents.

In conclusion, the researchers stated, “Recipients aged 14 to 16 years have the greatest risk of kidney allograft failure. Black adolescents and those with government insurance are at even higher risk. Private insurance reduces the risk of death across all ages. Comprehensive programs are needed for adolescents, especially for those at greater risk, to reduce graft loss during the transition from adolescence to adulthood.”