DEFING LONG TERM RENAL ALLOGRAFT SURVIVAL FOLLOWING EARLY CORTICOSTEROID WITHDRAWAL AND RISK FACTOR ASSESSMENT

THERAPEUTIC STRATEGIES FOR KIDNEY TRANSPLANTATION

A.R. Shields¹, R.R. Alloway², A. Govil², M. Cardi³, S. Safdar³, A. Tevar⁴, L. Arend⁵, A. Girnita⁶, J. Everly⁷, E.S. Woodle^4
1Transplant Surgery, University of Cincinnati, Cincinnati/Ohio/UNITED STATES OF AMERICA, ²Nephrology, University of Cincinnati, cincinnati/UNITED STATES OF AMERICA, ³Nephrology, The Christ Hospital, cincinnati/UNITED STATES OF AMERICA, ⁴Transplant Surgery, University of Cincinnati, cincinnati/UNITED STATES OF AMERICA, ⁵Pathology, University of Cincinnati, cincinnati/UNITED STATES OF AMERICA, ⁶Hoxworth Immunology, University of Cincinnati, cincinnati/UNITED STATES OF AMERICA, ⁷, Oncology Hematology, Inc, cincinnati/UNITED STATES OF AMERICA

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Introduction: Risk factors that influence renal allograft survival in early corticosteroid withdrawal (≤ 7 days of steroids, ECSWD) have not been defined, in part because large numbers of ECSWD patients with long-term follow-up have not previously been available for analysis. The purpose of this study is to determine risk factors for death-censored graft loss (DCGL) in ECSWD regimens. Methods: Data was collected prospectively in 630 patients who received ECSWD regimens from January 2000-August 2009 at our center. Risk factors evaluated in univariate analyses include: age, gender, race, repeat transplant, current cytotoxic PRA, peak cytotoxic PRA, DGF, DR mismatches (MM), AB MM, donor type (living versus deceased), donor age, donor race, donor gender, pretransplant diabetes type 1 and 2, and acute rejection (AR). Univariate analyses of individual risk factors were performed by chi-square analysis, with Cox Proportional Hazards regression performed for factors that entered the multivariate model (MVA). Variables with a p < 0.25 entered the multivariate model. Results: 57 of 630 patients (9%) experienced DCGL with a follow-up period of 1444 ± 915 days (mean ± SD) and median of 1399 days (range 1-3398). MVA results are presented in the table below. 51% of patients with DCGL experienced an AR compared to 15% without DCGL (p <0.0001). Mean time to first AR was significantly later in DCGL patients compared to patients not experiencing DCGL (458 ± 513 v 285 ± 482 days, p<0.01). Kaplan-Meier analysis revealed 10 yr death-censored GS of 82% in ECSWD Pts, with a graft half life of 28.8 years.

	UVA
		Hazard Ratio		p value
	Recipient Age	0.97		0.05
	Female recipient	0.74		0.03
	AA recipient	2.44		0.001
	Type I Diabetes	0.44		NS
	Type 2 Diabetes	1.27		NS
	Donor Age	1.01		NS
	AA Donor race	1.74		0.09
	Deceased Donor	2.13		0.005
	Living Related Donor	0.47		0.013
	Living Unrelated Donor	0.88		NS
	Current B Cell PRA	1.01		NS
	Peak B Cell PRA	1.02		0.03
	Current T Cell PRA	1.03		0.001
	Peak T Cell PRA	1.02		0.001
	DR Mismatch = 0	0.38		0.03
	DR Mismatch = 2	1.76		0.04
	DGF	3.28		0.001
	Acute Rejection (AR)	4.13		0.001
	Repeat Transplant	1.48		NS
MVA		HAZARD RATIO	P value	95% CI
Acute Rejection		4.77	0.006	1.561 – 14.61
African American Recipient		3.33	0.037	0.098 – 0.930
B Cell Peak PRA		1.12	0.001	1.057 – 1.204
B Cell Current PRA		0.90	0.010	0.840 – 0.976

Conclusion: AR and African American recipient race profoundly influence DCGL in ECSWD. The influence of HLA sensitization however is less clear. Additional studies areneeded to better define populations at increased risk for DCGL. This analysis indicates that DCGL risk factors under ECSWD are similar to those traditionally defined with conventionalimmunosuppression.

Disclosure: All authors have declared no conflicts of interest.