Reasons and effects of the decline of willing related potential living kidney donors

Table 1 Definitions of terms used to describe the living donors at different stages of kidney donation including access, counseling, evaluation, acceptance, candidacy, and donation with kidney transplantation of related intended patients

Term	Definition
PLD	An individual who confirmed his willingness to donate a kidney to an intended patient at the initial counseling settings and was ready to start the evaluation for kidney donation, regardless of the commencement of the evaluation
Related PLD	PLD who had a relative intended patient with end-stage renal disease up to the 4th degree of genetic relatedness. Regardless of their genetic relatedness, the wife or husband of a recipient was considered a related PLD
Excluded PLD	PLD who was disqualified as a kidney donor and excluded from the process of kidney donation by KT team due to causes that disqualify candidacy to donate a kidney, such as medical, immunological, or financial causes
Regressed PLD	PLD who withdrew his decision of kidney donation at any stage after an initial confirmation of the donation decision and before the operation
Released PLD1	PLD who was still willing and completed or was still continuing the evaluation, but the related intended patient was withdrawn from KT preparation due to any cause
Candidate PLD	PLD who completed all the steps of evaluation and was finally accepted by the KT team for kidney donation, regardless of the later regression or release from donation
Accepted PLD	PLD who completed the evaluation without exclusion from kidney donation and was accepted for donation without release or regression from his willingness
LD	PLD becomes a LD when he succeeds in donating a kidney to his/her intended patient, which also means KT was achieved
Relatedness degrees and forms2	First degree: father, mother, son, daughter, wife, and husband. Second degree: brother, sister, grandfather, grandmother, grandson, and granddaughter. Third degree: nephew, uncle and aunt. Fourth degree: cousins

¹In this study, release of the donor meant that the donor became free from any commitment to donating a kidney because his relative intended patient was excluded, regressed, or died. In addition, the donor would not be allocated to another patient, as he/she was willing to donate to his intended relative only.

²Husband-wife couples were processed as first-degree related potential living donors when donations were planned between each couple. However, they may be genetically related or unrelated, relative to their premarriage relatedness. KT: Kidney transplantation; LD: Living donor; PLD: Potential living donor.

Table 2 Demographic and clinical characteristics of patients and related potential living donors presented as total patients (n = 212) and as a comparison between patients with candidate (n = 74) and patients with non-candidate (n = 138) potential living donors

Characteristics	Total patients, n = 212	Patients with candidate PLDs, n = 74	Patients with non-candidate PLDs, n = 138	P value
	mean ± SD (range)/number (%)
Mean age in yr	31.2 ± 10.6 (13-66)	29.1 ± 9.6 (13-57)	32.9 ± 12.0 (14-66)	0.041
Sex, n = 212
Males	173 (81.6%)	67 (90.5%)	106 (76.8%)	0.087
Females	39 (18.4%)	7 (9.5%)	32 (23.2%)
Status of dialysis at presentation, n = 212
Preemptive	19 (9.0%)	5 (6.8%)	14 (10.1%)	0.462
On regular hemodialysis	193 (91.0%)	69 (93.2%)	124 (89.9%)
Primary kidney disease, n = 212
Unknown	167 (78.8%)	56 (75.7%)	111 (80.4%)	0.088
Systemic disease	14 (6.6%)	3 (2.7%)	11 (8.0%)
Glomerulonephritis	6 (2.8%)	3 (4.0%)	3 (2.2%)
Hereditary renal disease	5 (3.8%)	2 (2.7%)	3 (2.2%)
Obstructive uropathy	11 (5.2%)	8 (10.8%)	3 (2.2%)
Urolithiasis	9 (4.2%)	2 (2.7%)	7 (5.1%)
Categories of primary kidney disease, n = 212
Unknown	167 (78.8%)	56 (75.7%)	111 (80.4%)	0.154
Systemic disease	14 (6.6%)	3 (4.0%)	11 (8.0%)
Local, renal/urinary	31 (14.6%)	15 (20.3%)	16 (11.6%)
Patients per number of PLDs, n = 212
Patients with one PLD	165 (77.8%)	53 (71.6%)	112 (81.2%)	0.265
Patients with two PLDs	39 (18.4%)	17 (23.0%)	22 (15.9%)
Patients with three PLDs	8 (3.8%)	4 (5.4%)	4 (2.9%)

PLD: Potential living donor; SD: Standard deviation.

Table 3 Patient characteristics distributed per extent and outcome of evaluation of their potential living donors presented as total patients (n = 212) and as a comparison between patients with candidate (n = 74) and patients with non-candidate (n = 138) potential living donors.

Characteristics	Total patients, n = 212	Patients with candidate PLDs, n = 74	Patients with non-candidate PLDs, n = 138	P value
	mean ± SD (range)/number (%)
Patients per extent of evaluation of their PLDs1, n = 212
Completed 1	71 (33.5%)	54 (73%)	17 (12.3%)	< 0.001
Completed 1/incomplete 1	15 (7.1%)	7 (9.5%)	8 (5.8%)
Completed 1/incomplete 2	2 (0.9%)	2 (2.7%)	0 (0%)
Completed 1/not evaluated 1	7 (3.3%)	6 (8.1%)	1 (0.7%)
Completed 2	3 (1.4%)	3 (4.1%)	0 (0%)
Completed 2/incomplete 1	1 (0.5%)	0 (0%)	1 (0.7%)
Completed 3	2 (0.9%)	2 (2.7%)	0 (0%)
Incomplete 1	94 (44.3%)	0 (0%)	94 (68.1%)
Incomplete 1/not evaluated 1	1 (0.5%)	0 (0%)	1 (0.7%)
Incomplete 1/not evaluated 2	1 (0.5%)	0 (0%)	1 (0.7%)
Incomplete 2	13 (6.1%)	0 (0%)	13 (9.4%)
Incomplete 3	2 (0.9%)	0 (0%)	2 (1.5%)
Patients per acceptance of their PLDs1, n = 212
Accepted 1	44 (20.6%)	44 (59.5%)	0 (0%)	< 0.001
Accepted 1/excluded 1	8 (3.8%)	8 (10.8%)	0 (0%)
Accepted 1/excluded 2	2 (0.9%)	2 (2.7%)	0 (0%)
Accepted 1/not evaluated 1	4 (1.9%)	4 (5.4%)	0 (0%)
Excluded 1	81 (38.2%)	0 (0%)	81 (0%)
Excluded 2	14 (6.6%)	0 (0%)	14 (10.1%)
Excluded 3	2 (0.9%)	0 (0%)	2 (1.5%)
Excluded 1/released 1	5 (2.4%)	1 (1.4%)	4 (2.9%)
Excluded 1/regressed 1	3 (1.4%)	1 (1.4%)	2 (1.5%)
Excluded 1/not evaluated 1	2 (0.9%)	0 (0%)	2 (1.5%)
Excluded 1/not evaluated 2	1 (0.5%)	0 (0%)	1 (0.7%)
Excluded 2/released 1	2 (0.9%)	1 (1.4%)	1 (0.7%)
Excluded 2/regressed 1	1 (0.5%)	1 (1.4%)	0 (0%)
Released 1	28 (13.2%)	7 (9.5%)	21 (15.2%)
Released 1/not evaluated 1	2 (0.9%)	2 (2.7%)	0 (0%)
Regressed 1	12 (5.7%)	3 (4.1%)	9 (6.5%)
Regressed 2	1 (0.5%)	0 (0%)	1 (0.7%)

¹The numbers here refer to the number of potential living donors who had this characteristic. In addition, it included 10 potential donors who were not evaluated, and they presented here as part of the combined donors to the same patients with evaluated donors. PLD: Potential living donor; SD: Standard deviation.

Table 4 Patients distributed per characteristics of exclusion of their potential living donors presented as total patients (n = 212) and as a comparison between patients with candidate (n = 74) and patients with non-candidate (n = 138) potential living donors.

Characteristics	Total patients, n = 212	Patients with candidate PLDs, n = 74	Patients with non-candidate PLDs, n = 138	P value
	mean ± SD (range)/number (%)
Patients per number of excluded PLDs, n = 121
Patients with one excluded PLD	100 (82.6%)	10 (71.4%)	90 (84.1%)	0.764
Patients with two excluded PLDs	19 (15.7%)	4 (28.6%)	15 (14.0%)
Patients with three excluded PLDs	2 (1.7%)	0 (0%)	2 (1.9%)
Patients per causes of exclusion of their PLDs, n = 1211
Combined immunological and medical causes	14 (11.6%)	3 (21.4%)	11 (10.3%)	0.680
HLA-incompatibility	24 (19.8%)	3 (21.4%)	21 (19.6%)
ABO-incompatibility	20 (16.5%)	1 (7.1%)	19 (17.8%)
ABO and HLA-incompatibility	2 (1.7%)	0 (0%)	2 (1.9%)
Age	8 (6.6%)	0 (0%)	8 (7.5%)
Diabetes mellitus	4 (3.3%)	0 (0%)	4 (3.7%)
HCV positive	5 (4.1%)	2 (14.3%)	3 (2.8%)
Hypertension	11 (9.1%)	4 (28.6%)	7 (6.5%)
Leprosy	1 (0.8%)	0 (0%)	1 (0.9%)
Low GFR	4 (3.3%)	1 (7.1%)	3 (2.8%)
High potential recurrence of primary kidney disease	6 (5.0%)	0 (0%)	6 (5.6%)
Proteinuria	12 (9.9%)	0 (0%)	12 (11.2%)
Psoriasis	1 (0.8%)	0 (0%)	1 (0.9%)
Rheumatoid arthritis	1 (0.8%)	0 (0%)	1 (0.9%)
Urolithiasis	5 (4.1%)	0 (0%)	5 (4.7%)
Financial causes	3 (2.5%)	0 (0%)	3 (2.8%)
Patients per main category of causes of exclusion of their PLDs, n = 121
Combined immunological and medical causes	14 (11.6%)	3 (21.4%)	11 (10.3%)	0.866
Immunologic mismatches	46 (38%)	4 (28.6%)	42 (39.3%)
Medical causes	58 (47.9%)	7 (50.0%)	51 (47.7%)
Financial causes	3 (2.5%)	0 (0%)	3 (2.8%)
Patients per timing of PLDs regression, n = 18
During evaluation	13 (72.2%)	0 (0%)	13 (100.0%)	NA
After evaluation	5 (27.8%)	5 (100.0%)	0 (0%)
Patients per cause of release of PLDs, n = 37
Patient death	4 (10.8%)	3 (27.3%)	1 (3.9%)	0.186
Patient regression	22 (59.5%)	6 (54.5%)	16 (61.5%)
Patient non-candidacy	11 (29.7%)	2 (18.2%)	9 (34.6%)
Patients per timing of release of PLDs, n = 37
During evaluation	26 (70.3%)	0 (0%)	26 (100.0%)	NA
After evaluation	11 (29.7%)	11 (100.0%)	0 (0%)
Fate of patients with evaluated PLDs, n = 212
Transplantation in our center	58 (27.4%)	58 (78.4%)	0 (0%)	NA
Transplantation in another center	14 (6.6%)	1 (1.4%)	13 (9.4%)	0.024
On hemodialysis	122 (57.6%)	12 (16.2%)	110 (79.7%)	< 0.001
Death	9 (4.2%)	3 (4.1%)	6 (4.4%)	0.920
Unknown	9 (4.2%)	0 (0%)	9 (6.5%)	0.024

¹Regarding the exclusion due to anatomical abnormalities, they included ectopic pelvic kidney, solitary kidney, and hypoplastic kidney in 3 patients. They were included in donors with a low split glomerular filtration rate. However, kidneys with unilateral simple cysts in 2 patients and three renal arteries in 2 patients were not the cause of exclusion. In the former, the cysts were treated by marsupialization after perfusion and before implantation in the recipients. In the latter, the contralateral kidneys were donated. GFR: Glomerular filtration rate; HCV: Hepatitis C virus; HLA: Human leukocytic antigen; NA: Not available; PLD: Potential living donor; SD: Standard deviation.

Table 5 Characteristics of potential living donors presented as total (n = 257) and as a comparison between the candidate (n = 74) and non-candidate (n = 183) groups of donors

Characteristics	Total PLDs, n = 257	Candidate PLDs, n = 74	Non-candidate PLDs, n = 183	P value
	mean ± SD (range)/number (%)
Mean age in yr	40.5 ± 10.4 (18-65)	41.0 ± 10.5 (21-60)	40.4 ± 10.5 (18-65)	0.498
Sex
Female	169 (65.8%)	49 (66.2%)	120 (65.6%)	> 0.999
Male	88 (34.2%)	25 (33.8%)	63 (34.4%)
Form of relatedness1
Aunt	4 (1.6%)	4 (5.4%)	0 (0%)	0.286
Brother	51 (19.8%)	14 (18.9%)	37 (20.2%)
Cousin	4 (1.6%)	0 (0%)	4 (2.2%)
Daughter	4 (1.6%)	1 (1.4%)	3 (1.6%)
Father	23 (8.9%)	7 (9.5%)	16 (8.7%)
Husband	6 (2.3%)	2 (2.7%)	4 (2.2%)
Mother	76 (29.6%)	23 (31.1%)	53 (29%)
Nephew	1 (0.4%)	0 (0%)	1 (0.6%)
Sister	53 (20.6%)	13 (17.6%)	40 (21.9%)
Son	4 (1.6%)	1 (1.4%)	3 (1.6%)
Uncle	1 (0.4%)	1 (1.4%)	0 (0%)
Wife	30 (11.7%)	8 (10.8%)	22 (12.0%)
Degree of relatedness
First	143 (55.6%)	42 (56.8%)	101 (55.2%)	0.020
Second	104 (40.5%)	27 (36.5%)	77 (42.1%)
Third	6 (2.3%)	5 (6.8%)	1 (0.6%)
Fourth	4 (1.6%)	0 (0%)	4 (2.2%)
Extent of evaluation
Complete	109 (42.4%)	74 (100.0%)	35 (19.1%)	NA
Incomplete	148 (57.6%)	0 (0%)	148 (80.9%)
Fate of PLDs
Donated	58 (22.6%)	58 (78.4%)	0 (0%)	NA
Excluded	144 (56.0%)	0 (0%)	144 (78.7%)	NA
Regressed2	18 (7.0%)	5 (6.8%)	13 (31.6%)
During evaluation	13 (72.2%)	0 (0%)	13 (100.0%)	NA
After evaluation	5 (27.8%)	5 (100%)	0 (0%)
Released	37 (14.4%)	11 (14.9%)	26 (68.4%)
Causes of donor release
Patient death	4 (10.8%)	3 (27.3%)	1 (3.9%)	0.186
Patient regression	22 (59.5%)	6 (54.5%)	16 (61.5%)
Patient non-candidacy	11 (29.7%)	2 (18.2%)	9 (34.6%)
Timing of PLDs release
During evaluation	26 (70.3%)	0 (0%)	26 (100.0%)	NA
After evaluation	11 (29.7%)	11 (100.0%)	0 (0%)
Time spent in PLDs evaluation in mo	2.2 ± 1.5 (0.5-6.0)	4.0 ± 0.9 (1-6)	1.5 ± 1.2 (0.5-5.0)	< 0.001

¹Among the 6 husband and 30 wife potential living donors (PLDs), only 13 of them were genetically related PLDs to their intended recipients (due to consanguineous marriage);

²The reason of regression was the fear of health drawbacks from donation in all PLDs. NA: Not available; PLD: Potential living donor; SD: Standard deviation.

Table 6 Multivariate logistic regression of the potential variables influencing the candidacy of potential living donors with a completed preparation

Variables	Modality	Odds ratio	P value
Dialysis status	Preemptive vs on dialysis	0.66 (0.23-1.94)	0.451
Number of potential donors	Single vs multiple	1.69 (0.87-3.28)	0.123
Donor age	Increasing age	1.0 (0.97-1.03)	0.925
Donor sex	Men vs women	1.02 (0.55-1.92)	0.940
Relatedness degree	First vs more than first	1.07 (0.55-2.1)	0.834