The prevalence of end-stage renal disease (ESRD) has continued to increase rapidly and thus the need for compatible organs. For patients with ESRD, the best treatment option is kidney transplantation, due to an improved quality of life and increased survival (1–4). Living donor transplantation has been shown to increase survival over cadaveric donation by shortening or eliminating the time on the transplant waiting list and allowing transplantation to occur preemptive to dialysis (5, 6).
Donating a kidney has been shown to be a safe procedure for healthy individuals and an effective treatment option for patients with ESRD. Kidney donors undergo stringent medical evaluation to determine their suitability for donation, as it is mandatory that live kidney donations not impair the health of the donor.
Previous studies have shown no increased renal functional deterioration among past donors (7, 8) and rates of hypertension among past donors are actually lower than age-matched rates (8). Norwegian and Swedish studies have shown increased survival in kidney donors, a fact most probably explained by strict health criteria prior to donation (9, 10). Donors report an increased quality of life after donation due to enhanced self-esteem, which is heightened further when the transplant is successful (11–15).
As of November 2005, there were 63,486 patients on the national kidney transplant waiting list and this figure quantifies the enormity of the need for suitable donor organs (16). There are 578 persons on the South Carolina kidney transplant waiting list, of which 394 are African American (68.2%) (16). In South Carolina, 53% of patients listed for a transplant have been on the waiting list for longer than two years (16). The majority of the population of the waiting list in SC is African American, yet the majority of donors (living and cadaveric) are non-African American. This results in a much longer waiting time for African Americans (420 days) versus non-African Americans (261 days) (16). The need for living donor organs is especially pronounced in the African American population and long waiting times on kidney transplant lists have encouraged donation from living donors.
With rates of ESRD and kidney failure continuing to increase, the need for compatible organs continues to grow. Demands can not be met by cadaveric kidneys alone and thus living kidney donors are essential. While many potential donors are referred for organ donation, only very small percentages eventually donate a kidney. The reasoning behind high rates of nondonation has not been well studied. Research in this area will elucidate reasons for nondonation, establish racial differences if they exist, and determine if nondonation is based on medical reasons or simply an unwillingness to donate.
Design, Setting, and Patients
The Medical University of South Carolina (MUSC) Department of Transplant Surgery maintains an on-going kidney transplant database containing information on potential kidney transplant recipients and donors. A retrospective database and chart review of all patients that were referred to the transplant center for potential live kidney donation from January 1, 2000 to December 31, 2004 was performed. Potential donors were not included in the study if certain demographic data including gender and race was not ascertainable.
The referral for potential live kidney donation is received by one of two means: 1) potential transplant recipients compile a list of family and friends they feel may be interested in donating, and/or 2) potential donors contact the transplant office about potential donation independently. The living donor transplant coordinator (LDTC) gathers basic information including demographics and medical history from potential donors. The LDTC also requests the potential donors ABO type and blood pressure.
If cleared, orders are sent to the potential donor to supply basic lab work, including body mass index (BMI), blood typing and pressure measurement, metabolic profile, and two 24-hr urine collections. If the potential donor is deemed medically suitable and compatible with the potential recipient, the potential donor schedules a visit to the transplant center where they undergo a more stringent medical evaluation, including preliminary crossmatch. Next, the potential donor sees the transplant surgeon, nephrologists, and a social worker or psychologist/psychiatrist to ensure the donor comprehends all of the risks involved with donation and that the donor is not being coerced to donate.
Reasons for Nondonation
Potential donations may be halted for many reasons including the following: lost to follow-up, donor health, incompatible blood type, positive crossmatch, or age (too young or old). Potential donors are deemed medically unsuitable for a variety of reasons, all of which are to ensure safety to the donor.
Blood pressure greater than 140/90 mm Hg is an absolute contraindication for donation. Blood pressure of 120–140/90 mm Hg is considered borderline and requires 24 hr ambulatory monitoring and if 10% of diastolic readings are greater than 85 mm Hg, the donor is excluded. A patient is considered ineligible for donation if they are pregnant, have diabetes, are young (<30 years of age) and have a strong family history of diabetes, gestational diabetes, or hypertension, or a BMI ≥30. Donors with a history of malignancy (excluding skin cancer), liver problems (positive serology for hepatitis B/C, or elevation of amino alanine transferase (ALT) or aspartate amino transferase (AST) of 1.5 times normal), kidney stones, chronic pancreatitis, bladder problems, creatinine clearance <80 cc per minute, proteinuria, or microalbuminuria are excluded. All potential donors must pass psychiatric evaluation by a clinical psychologist who subjectively decides if the donor is mentally cognizant and fully aware of the risks involved for informed consent.
Other reasons for halting potential donations are recipient based and may include: recipient receiving another organ (cadaveric or living), recipient not cleared for transplant (too sick), moved out of state, declined donation from potential living donor, and death.
Data Collection and Statistical Analysis
Data from donor referrals were collected and stored in the kidney transplant research database. Hard copies of patient files were reviewed to minimize missing data. All data were analyzed with SAS statistical software version 9.1 (SAS Institute, Cary, NC). Reasons for nondonation were analyzed overall and by race using frequencies and chi square tests of homogeneity in contingency tables to test for differences in collapsed categories and expanded subcategories.
Characteristics of Referred Potential Donors
From January 1, 2000 to December 31, 2004, there were 1,857 prospective donors referred to the transplant center for potential live kidney donation. Of these, 1,711 met the inclusion criteria. Fifty potential donors were currently being evaluated, six were referrals for recipients awaiting transplant in another state, 86 were deleted due to missing race, and four for missing gender.
In all, 519 potential donors (30.3%) were lost to follow-up. African Americans (55.9%) represented a significantly greater proportion (P<0.01) of referrals that were lost to follow-up compared to non-African Americans (44.1%). Since the database did not allow us to determine at what point in the referral process potential donors were lost, these patients were removed from the study population.
Additionally, nine (1.3%) African Americans and 14 (1.4%) non-African Americans did not donate for unknown reasons and were also removed from the analysis. From the 1,169 remaining, 10.2% donated their kidney and significantly more (P=0.01) were non-African American (n=100, [13.2%]) than African American (n=19, [4.6%]). Those who donated were removed from the analysis and the remaining results focus on patients (n=1,050) whose reason for nondonation is documented.
The demographic breakdown of the referred donors showed the majority to be non-African American (62.6%, n=657) and female (61.5%, n=646). Information on age was missing for 92 patients that were included in the final analysis. However, for non-missing data (n=958), the range varied from 13 to 89 years, with the mean age of referred patients being 40.8±12.7 years. A total of 1,050 potential donors were halted for reasons described below.
Reasons for Nondonation
The reasons for nondonation are shown in Figure 1. The primary reason for nondonation was related to donor health (43.1%) followed closely by recipient based reasons (41.3%, see below). Immunologic incompatibilities (ABO type [7.1%] or positive crossmatch [2.6%]) between the donor and recipient only accounted for a total of 9.7% of nondonations. Other reasons for nondonation included age (1.8%), insurance (0.6%) and the potential donor declining to donate (3.5%).
Recipient-based Reasons for Nondonation
Overall, recipient causes accounted for 41.3% of all nondonations. These reasons are broken down into subcategories in Table 1. The primary recipient based reason for potential donor nondonation was because potential recipients were not cleared (too sick) for transplant (n=200, 46.1%). One hundred and sixty three (37.6%) of patients in need of a transplant received an organ from another source, including another living donor or a cadaver, but the data did not allow differentiation. Forty two (9.7%) potential recipients died while awaiting transplant, 19 (4.4%) declined the live donation, and 10 (2.3%) moved out of state and were no longer followed.
Medical Reasons for Nondonation
The primary (43.1%, n=452) documented cause of nondonation was donor health issues (Table 2). The presence of, family history of, or high risk for diabetes, gestational diabetes, and/or hypertension was the number one health-related reason for termination (41.8%). This was followed closely by high body mass index (BMI) (25.4%). Other reasons for termination of evaluation included kidney, pancreas, bladder or liver problems (8.0%), unsuitable creatinine clearance (5.1%; 2 too high, 21 too low), proteinuria (4.6%), pregnancy (1.8%), psychiatric issues (1.8%) and other past medical problems (4.4%) including cancer, lupus, heart disease and hepatitis.
Racial Differences in Donation and Nondonation
Nondonation was analyzed by race and is shown in Table 3. With subcategories collapsed, differences in nondonation were similar across groups. However, significantly (P<0.01) more African American donors (9.7%) were halted because of incompatible blood types when compared to non-African Americans (5.6%).
Significantly more (P=0.01) non-African Americans (n=100, [13.2%]) than African Americans (n=19, [4.6%]) donated their kidney. This difference remained even after recipient based reasons (declining donation or receiving an organ from another source) for nondonation were removed (16.6% versus 6.5%, [P<0.01]).
Racial Differences in Recipient-based Reasons for Nondonation
Recipient based reasons for donor nondonation did not differ overall between races. When this category was expanded to include subcategories (Table 4), far more African Americans (70.5%) than non-African Americans (33.3%) were not cleared for transplant (P<0.01). More non-African Americans died (13.0% versus 3.4% [P≤0.01]) or moved (3.5% versus 0%, [P=0.02]) while awaiting transplant than African Americans. A significantly greater percentage of non-African Americans than African Americans received an organ from another source (may be cadaveric or living) (46.3% versus 20.8%, respectively [P≤0.01]).
Racial Differences in Medical Reasons for Nondonation
Donor health reasons for nondonation did not differ overall between races. These reasons were expanded to include subcategories and were analyzed by race and are shown in Table 5. African American causes for nondonation were more often attributed to high BMI (32.0% versus 21.2%), [P<0.01]). Significantly more non-African Americans were halted due to kidney, pancreas, bladder or liver problems (P=0.03), unspecified health problems (P=0.04), and other medical conditions (P=0.02) but our data did not allow us to explore this in detail.
Live kidney donation continues to offer the best treatment option for patients in need of a transplant. Live donor transplantation has been shown to increase graft survival in patients (1–4) and has shown to be safe and have no long-term side effects to the donor (7, 8). With the increase in rates of ESRD and the number of patients waiting for a kidney transplant, there is a substantial need to increase the rates of live organ donation in this patient population.
A large proportion of our potential donor population is lost to follow-up (30.3%). Patients in need of a kidney transplant provide the transplant center with contact information for potential donors or individuals that are interested in donating contact the transplant center independently. After initial contact is made, the potential donor provides the transplant coordinator with basic information, has simple medical tests performed, and then schedules an extensive medical evaluation to ensure the potential donor is a candidate for donation. The transplant coordinator may be unable to reach the potential donor upon referral from the ESRD patient or they may lose contact with them at any time afterwards, such as during any point of their medical evaluation. All of these patients are considered “lost to follow-up.”
With such a large percentage of patients being lost to follow-up, notably in African Americans, transplant programs would benefit from increasing efforts to contact and stay in touch with potential donors. It is also possible that potential donors are being scared or turned-off from the transplant procedure after medical testing or meeting with the surgeon. Transplant programs should aim to educate potential donors on the minimal risk and extreme satisfaction early in the donation process to avoid potential dropout and maximize the number of living donor candidates. Such efforts are currently being employed at our university (17, 18).
Results from this study indicated that only a small percentage (10.2%) of all donors referred to a large Southeastern transplant center for potential live kidney donation actually donate their kidney. Studies investigating the reasons potential live kidney donations are halted are lacking, and to our knowledge, no studies have reported on racial differences of nondonation.
The structure of the transplant database used in this study introduced certain limitations. It was not possible to match potential donors and recipients so it is unknown how many referrals for potential donation were associated with a single transplant candidate recipient. It was also not possible to separate causes of nondonation due to presence of or family history/high risk for diabetes and hypertension. Missing data may have introduced selection bias and skewed results in an indeterminate manner. Despite these limitations, these results are an important first step in determining reasons for nondonation and understanding low rates of live kidney donation.
Immunologic incompatibilities seem the most rational explanation one willing to donate an organ would be halted and the most commonly documented reason (19–21). However, our study showed that only 9.7% of nondonations were due to such causes (ABO mismatch or positive crossmatch), indicating other factors account for nondonation with much greater regularity.
Recipient-based causes accounted for 41.3% of all nondonations and included the recipient being ineligible (not cleared) for transplant, declining donation, moving out of state, death, or being transplanted with another organ. Although the overall percentage of recipient causes for nondonation did not differ between races, significant distinctions were seen when these reasons were further separated into subcategories.
The recipient being ineligible for transplant accounted for a larger percentage of African American recipient-based nondonations (70.5% versus. 33.3%, respectively, P<0.01), indicating a greater proportion of African Americans are too sick or medically unsuitable for a transplant. A greater percentage of non-African Americans were transplanted with other cadaveric or live donor organs (46.3% versus 20.8%, respectively, P≤0.01). This may be due to either more appropriately matched cadaver kidneys becoming available (the majority of cadaver kidneys are non-African American) or a larger non-African American living donor pool referred meeting donation eligibility. Unfortunately, our data did not allow us to differentiate between recipients that were transplanted with cadaver or live donor kidneys, which is a limitation of this study.
The primary documented cause for nondonation was due to donor health issues, with diabetes/hypertension and BMI comprising the majority of causes for both races. No difference was seen in the proportion of terminations between races for diabetes and hypertension, but nondonation due to high BMI was greater in African Americans for termination due to high BMI (P≤0.01).
African Americans are generally in poorer health than non-African Americans with higher rates of diabetes and hypertension in the general population and would thus seem to be more likely to be medically unsuitable live donors (22–25). Results from our study indicated that of those willing to be a live donor, rates of nondonation due to diabetes and hypertension did not differ between races.
Significantly more non-African Americans were halted due to kidney, pancreas, bladder or liver problems, unspecified health problems, and other medical conditions. Our data did not allow us to examine these reasons in detail, and this finding is most likely the result of small sample size and reflects trivial percentages for nondonation.
African Americans report a higher quality of life on dialysis than non-African Americans and may view the need for transplant as less substantial (26, 27). Some African Americans may have religious concerns preventing them from donating or asking for a live donation. Some African Americans may believe the outcome of their illness is controlled by a higher power or that the body must be buried intact (28–30). These factors may make African Americans less inclined to ask for a live donation and less likely to be a willing live donor than non-African Americans (31, 32).
Although the majority of donor referrals were non-African American (62.6%), the majority (68.5%) of patients comprising the waiting list were African American. This may indicate a disparity in the number of willing donors in the African American community. African Americans generally show distrust in the medical system, experience less access to care, and lack education as some ESRD patients do not realize living donor transplantation is a treatment option (33–35).
Although transplant team efforts continue to encourage live donation, rates still remain low, particularly in African Americans where this disparity is especially pronounced. Determining the reason behind nondonation is a first step towards understanding low rates of live kidney donation and deciphering if reasons are based on a lack of willing donors or if willing donors are found to be medically unsuitable. Important findings from this study show that more African American donor referrals are lost to follow-up while rates of other reasons were similar among races. Data from this study indicated that African Americans are not more medically unsuitable than non-African Americans, thus we may hypothesize that the divergence in rates of live kidney donation is caused by a disparity in willingness to donate among African Americans.
Increasing disease rates and a shortage of organs suitable for African Americans have caused the disparity in kidney transplantation to continue to grow. Learning about differences in nondonation may help the medical community to focus intervention strategies to increase willingness to be a live donor, and ultimately lessen the burden of this disparity.
This study was supported by grant R01DK62596-02 from the National Institute of Diabetes and Digestive and Kidney Diseases: A Program to Increase Living Donations in African Americans.
1. Binet I, Bock AH, Vogelbach P, et al. Outcome in emotionally related living kidney donor transplantation. Nephrol Dial Transplant
1997; 12(9): 1940.
2. Medin C, Elinder CG, Hylander B, et al. Survival of patients who have been on a waiting list for renal transplantation. Nephrol Dial Transplant
2000; 15(5): 701.
3. Wolfe RA, Ashby VB, Milford EL, et al. Comparison of mortality in all patients on dialysis, patients on dialysis awaiting transplantation, and recipients of a first cadaveric transplant. N Engl J Med
1999; 341(23): 1725.
4. Rabbat CG, Thorpe KE, Russell JD, Churchill DN. Comparison of mortality risk for dialysis patients and cadaveric first renal transplant recipients in Ontario, Canada. J Am Soc Nephrol
2000; 11(5): 917.
5. Kasiske BL, Snyder JJ, Matas AJ, et al. Preemptive kidney transplantation: the advantage and the advantaged. J Am Soc Nephrol
2002; 13(5): 1358.
6. Meier-Kriesche HU, Kaplan B. Waiting time on dialysis as the strongest modifiable risk factor for renal transplant outcomes: a paired donor kidney analysis. Transplantation
2002; 74(10): 1377.
7. Eberhard OK, Kliem V, Offner G, et al. Assessment of long-term risks for living related kidney donors by 24-h blood pressure monitoring and testing for microalbuminuria. Clin Transplant
1997; 11(5 Pt 1): 415.
8. Goldfarb DA, Matin SF, Braun WE, et al. Renal outcome 25 years after donor nephrectomy. J Urol
2001; 166(6): 2043.
9. Fehrman-Ekholm I. Life-span of living-related kidney donors. Transplant Proc
1997; 29(7): 2801.
10. Fehrman-Ekholm I, Elinder CG, Stenbeck M, et al. Kidney donors live longer. Transplantation
1997; 64(7): 976.
11. Johnson EM, Anderson JK, Jacobs C, et al. Long-term follow-up of living kidney donors: quality of life after donation. Transplantation
1999; 67(5): 717.
12. Schover LR, Streem SB, Boparai N, et al. The psychosocial impact of donating a kidney: long-term follow-up from a urology based center. J Urol
1997; 157(5): 1596.
13. Westlie L, Fauchald P, Talseth T, et al. Quality of life in Norwegian kidney donors. Nephrol Dial Transplant
1993; 8(10): 1146.
14. Isotani S, Fujisawa M, Ichikawa Y, et al. Quality of life of living kidney donors: the short-form 36-item health questionnaire survey. Urology
2002; 60(4): 588.
15. Hartmann A, Fauchald P, Westlie L, et al. The risk of living kidney donation. Nephrol Dial Transplant
2003; 18(5): 871.
16. Data Query. Organ Procurement and Transplantation Network. Available at http://www.OPTN.org
. Accessed Nov 1, 2005.
17. Lunsford SS, Chavin KD, Hildebrand LG, et al. Racial differences in coping with the need for kidney transplantation and willingness to ask for live organ donation. Am J Kidney Dis
2006; 47(2): 324.
18. Shilling LN, Chavin KD, Hildebrand LG, et al. Healthcare professionals’ perceptions of the barriers to living donor kidney transplantation among African Americans. J Natl Med Assoc
2006; 98(6): 834.
19. Fehrman-Ekholm I, Gabel H, Magnusson G. Reasons for not accepting living kidney donors. Transplantation
1996; 61(8): 1264.
20. Calder FR, Chang RW. Panning for gold: screening for potential live kidney donors. Nephrol Dial Transplant
2004; 19(5): 1276.
21. Muthusethupathi MA, Rajendran S, Jayakumar M, Vijayakumar R. Evaluation and selection of living related kidney donors–our experience in a government hospital. J Assoc Physicians India
1998; 46(6): 526.
22. Jamerson KA. Preventing chronic kidney disease in special populations. Am J Hypertens
2005; 18(4 Suppl): 106.
23. Miller ST, Schlundt DG, Larson C, et al. Exploring ethnic disparities in diabetes, diabetes care, and lifestyle behaviors: the Nashville REACH 2010 community baseline survey. Ethn Dis
2004; 14(3 Suppl 1): S38.
24. Douglas JG. Clinical guidelines for the treatment of hypertension in African Americans. Am J Cardiovasc Drugs
2005; 5(1): 1.
25. Ferdinand KC, Clark LT. The epidemic of diabetes mellitus and the metabolic syndrome in African Americans. Rev Cardiovasc Med
2004; 5 (Suppl 3): S28.
26. Hicks LS, Cleary PD, Epstein AM, Ayanian JZ. Differences in health-related quality of life and treatment preferences among black and white patients with end-stage renal disease. Qual Life Res
2004; 13(6): 1129.
27. Unruh M, Miskulin D, Yan G, et al. Racial differences in health-related quality of life among hemodialysis patients. Kidney Int
2004; 65(4): 1482.
28. Satcher D. Eliminating disparities, promoting partnerships. Mayo Clin Proc
1999; 74(8): 838.
29. Curlin FA, Roach CJ, Gorawara-Bhat R, et al. How are religion and spirituality related to health? A study of physicians’ perspectives. S Med J
2005; 98(8): 761.
30. Ellison CG. Race, religious involvement and depressive symptomatology in a southeastern U.S. community. Soc Sci Med
1995; 40(11): 1561.
31. Minniefield WJ, Yang J, Muti P. Differences in attitudes toward organ donation among African Americans and whites in the United States. J Natl Med Assoc
2001; 93(10): 372.
32. Sehgal AR. The net transfer of transplant organs across race, sex, age, and income. Am J Med
2004; 117(9): 670.
33. Siminoff LA, Arnold R. Increasing organ donation in the African-American community: altruism in the face of an untrustworthy system. Ann Intern Med
1999; 130(7): 607.
34. Wolfe RA, Ashby VB, Milford EL, et al. Differences in access to cadaveric renal transplantation in the United States. Am J Kidney Dis
2000; 36(5): 1025.
35. Young CJ, Gaston RS. Renal transplantation in black Americans. N Engl J Med
2000; 343(21): 1545.