The role of social networks: A novel hypothesis to explain the phenomenon of racial disparity in kidney transplantation

Abstract

Editorial, p. 861 Compared with dialysis therapy, it has been shown that kidney transplantation provides patients with end-stage renal disease (ESRD) improved physical and mental health, and is more cost-effective.1Becker BN Becker YT Pintar T et al.Using renal transplantation to evaluate a simple approach for predicting the impact of end-stage renal disease therapies on patient survival: Observed/expected life span.Am J Kidney Dis. 2000; 35: 653-659Abstract Full Text Full Text PDF PubMed Scopus (13) Google Scholar, 2Wolfe R Ashby V Milford E 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: 1725-1730Crossref PubMed Scopus (3908) Google Scholar However, rates of transplantation referrals are not consistent among ethnic groups of patients with ESRD. African Americans are much less likely than white patients with ESRD to be referred for a renal transplant, placed on a waiting list for a kidney, or receive a kidney transplant.3Alexander G Sehgal A Barriers to cadaveric renal transplantation among blacks, women, and the poor.JAMA. 1998; 280: 1148-1152Crossref PubMed Scopus (399) Google Scholar, 4Kasiske BL London W Ellison MD Race and socioeconomic factors influencing early placement on the kidney transplant waiting list.J Am Soc Nephrol. 1998; 9: 2142-2147PubMed Google Scholar, 5Ozminkowski R White A Hassol A Murphy M Minimizing racial disparity regarding receipt of a cadaver kidney transplant.Am J Kidney Dis. 1997; 30: 749-759Abstract Full Text PDF PubMed Scopus (52) Google Scholar Conclusions on these disproportionate levels of transplantation referrals have not included many theoretically substantiated causes or solutions. The US Department of Health and Human Services, commenting on this problem, reported: “This and other research does not allow us to identify with certainty the factors which prevent equitable access to organ transplantation.”6US Department of Health and Human Services 1999 Report to Congress on the Scientific and Clinical Status of Organ Transplantation.in: US Department of Health and Human Services, Washington, DC1999: 6Google Scholar Explanations for minority underutilization of transplantation as a treatment modality for ESRD have included socioeconomic, medical, and patient-preference factors. Because African Americans are less likely to have health insurance and generally have lower socioeconomic status than Caucasians,5Ozminkowski R White A Hassol A Murphy M Minimizing racial disparity regarding receipt of a cadaver kidney transplant.Am J Kidney Dis. 1997; 30: 749-759Abstract Full Text PDF PubMed Scopus (52) Google Scholar, 7Kiefer C Health Work With the Poor: A Practical Guide. Rutgers University Press, New Brunswick, NJ2000Google Scholar many have theorized that insurance and socioeconomic status are determining factors regarding the significant racial disparity among kidney transplantation referrals. However, there is no evidence that inadequate black insurance coverage is responsible for the grossly disproportionate rates of transplantation referrals because this significant disparity exists even after controlling for socioeconomic and insurance status.4Kasiske BL London W Ellison MD Race and socioeconomic factors influencing early placement on the kidney transplant waiting list.J Am Soc Nephrol. 1998; 9: 2142-2147PubMed Google Scholar, 8Gaylin D Held P Port F et al.The impact of comorbid and sociodemographic factors in access to renal transplantation.JAMA. 1993; 269: 603-608Crossref PubMed Scopus (230) Google Scholar There may be medical factors explaining lower transplantation rates for black patients with ESRD because African Americans wait longer for a kidney transplant than white patients.6US Department of Health and Human Services 1999 Report to Congress on the Scientific and Clinical Status of Organ Transplantation.in: US Department of Health and Human Services, Washington, DC1999: 6Google Scholar However, an extensive literature search was unable to show evidence linking a longer wait time for a kidney transplant to less interest or evaluation for such among black patients with ESRD. Fewer organ donations among blacks may be caused by the third explanation offered to date regarding the incongruity of kidney transplantation referrals in black patients: patient preference and distrust of the medical community. Black patients have been found to be more likely than white patients to have religious objections or problems with the concept of cadaveric transplantation.5Ozminkowski R White A Hassol A Murphy M Minimizing racial disparity regarding receipt of a cadaver kidney transplant.Am J Kidney Dis. 1997; 30: 749-759Abstract Full Text PDF PubMed Scopus (52) Google Scholar However, a literature review failed to find evidence that religious objection is linked to a majority of black disinterest in transplantation and also failed to locate a religious doctrine against transplantation. When studying reasons for African Americans refusal of organ donation, religious myths and misperceptions, distrust of the medical community, and racism have been among the reasons for refusal.9Siminoff L Sturm C African-American reluctance to donate: Beliefs and attitudes about organ donation and implications for policy.Kennedy Inst Ethics J. 2000; 10: 59-74PubMed Google Scholar, 10Davidson MN Devney P Attitudinal barriers to organ donation among black Americans.Transplant Proc. 1991; 23: 2531-2532PubMed Google Scholar However, there is yet to be evidence linking this distrust to less interest in obtaining a kidney transplant. The lack of a strongly supported conceptual framework behind these explanations, along with findings that black dialysis patients are not significantly different from white patients in their interest in receiving a transplant,3Alexander G Sehgal A Barriers to cadaveric renal transplantation among blacks, women, and the poor.JAMA. 1998; 280: 1148-1152Crossref PubMed Scopus (399) Google Scholar leads to a search for an alternative explanation for the phenomenon of racially disparate transplantation referrals. A novel manner by which to study and possibly explain this occurrence would be to use a sociological approach to understand the process by which African-American patients with ESRD obtain information regarding transplantation. Previous explanations for the racial disparity in kidney transplantation have failed to take such an approach, neglecting the possible role of social relations and social support networks in this information-dissemination process. Cognitive social support, ie, information about such complex medical procedures as transplantation, may not be available in some African-American communities. It is hypothesized here that the structural attributes of African-American social support networks may account for a lack of cognitive exchanges regarding the benefits and process involved in kidney transplantation, in turn, accounting for fewer African Americans pursuing kidney transplantation. Social support relationships may vary across groups in different structural positions in society, such as among different ethnic groups. This variation in social support networks may provide differential exposure to opportunities that can shape social relationship structures and processes of social role transformation and information exchange.11House J Kahn R Measures and concepts of social support.in: Social Support and Health. Academic, Orlando, FL1985: 83-108Google Scholar A social network is derived from sets of relationships between members of social systems or is a group of individuals in contact with each other who provide one another with goods or services.12Hall A Wellman B Social networks and social support.in: Social Support and Health. Academic, Orlando, FL1985: 23-41Google Scholar Kelly13Kelly M Social and cultural capital in the urban ghetto: Implications for the economic sociology of immigration.in: The Economic Sociology of Immigration: Essays on Networks, Ethnicity, and Entrepreneurship. Sage, New York, NY1995: 213-243Google Scholar reports that one of the most important attributes of social networks is their multiplexity, or composition of individuals who provide diverse social linkages. These linkages, or weak ties, are discussed fully in Granovetter's14Granovetter M Afterward 1994: Reconsiderations and a new agenda.in: ed 2. Getting a Job: A Study of Contacts and Careers. University of Chicago Press, Chicago, IL1994: 139-182Google Scholar approach to social networks, which introduced the concept of weak social ties, which can be classified as one's distant acquaintances or contacts. Granovetter14Granovetter M Afterward 1994: Reconsiderations and a new agenda.in: ed 2. Getting a Job: A Study of Contacts and Careers. University of Chicago Press, Chicago, IL1994: 139-182Google Scholar posits that a lack of weak ties deprives individuals of networking opportunities derived from social interaction (which provide information diffusion). In addition, he contends that it is not just the strength of the tie, but also the characteristics of that tie; it needs to be a link, or a bridge, to information and resources. Attributes of tie strength have been systematically linked to social mobility in regard to employment attainment. Accordingly, it has been determined that: (1) homogeneous social networks with high density and strong ties have been linked to the maintenance of social identity, and (2) heterogeneous social networks with lower density and weaker ties facilitate change in social role and identity and provide greater assistance with transition and adjustment to new circumstances.15House JS Umberson D Landis KR Structures and processes of social support.Annu Rev Soc. 1988; 14: 293-318Crossref Google Scholar, 16Vaux A Harrison D Support network characteristics associated with support satisfaction and perceived support.Am J Community Psychol. 1985; 13: 245-267Crossref Scopus (167) Google Scholar Research has shown economic and racial differences in the features of social networks, with those in higher socioeconomic classes having a more heterogeneous source of contacts and enhanced social resources for fellow members of the same social class.17Goldstein JR Warren JR Socioeconomic reach and heterogeneity in the extended family: Contours and consequences.Soc Sci Res. 2000; 29: 382-404Crossref Scopus (20) Google Scholar Lower income minority communities have been shown to be more restrictive than their more advantaged white peers and less apt to emphasize institutional connections.18Mindel C Wright R The use of social services by black and white elderly: The role of social support systems.J Gerontol Soc Work. 1982; 4: 107-125Crossref Scopus (61) Google Scholar African Americans are more likely than whites to obtain social support from strong ties, ie, their family, friends, and church, and have more homogeneous social networks.18Mindel C Wright R The use of social services by black and white elderly: The role of social support systems.J Gerontol Soc Work. 1982; 4: 107-125Crossref Scopus (61) Google Scholar, 19Lee BA Campbell KE Neighbor networks of black and white Americans.in: Networks in the Global Village. Westview, Boulder, CO1999: 119-146Google Scholar, 20Malson M The social-support systems of black families.Marriage Fam Rev. 1982; 5: 37-57Crossref Scopus (23) Google Scholar In summation, previous work has shown differences between social network structures of African Americans and Caucasians and also that more heterogeneous weakly linked networks are more conducive to social role transformation. It is proposed here that concepts related to social network theory can be extrapolated to the study of racial disparity in kidney transplantation. Weak ties possibly could lead to better health outcomes. White patients with ESRD may have better social resources that bridge them to enhanced information about transplantation and result in better patient outcomes, ie, they are referred more often for kidney transplantation, facilitating a social role transformation from dialysis to transplant patient. I hypothesize that a richer, more diverse source of information about the transplantation process and its benefits is attainable through weak ties. This is in accordance with the deduction of Horner et al21Horner R Oddone E Matchar D Theories explaining racial differences in the utilization of diagnostic and therapeutic procedures for cerebrovascular disease.Milbank Q. 1995; 73: 443-461Crossref PubMed Scopus (68) Google Scholar that incomplete information about treatment options may be a significant barrier for blacks in pursuing health care. Many times, there can be a lack of information provided to patients regarding all ESRD treatment modalities and, specifically, how to go about being listed for a kidney transplant. Alexander and Sehgal,22Alexander G Sehgal A Why hemodialysis patients fail to complete the transplantation process.Am J Kidney Dis. 2001; 37: 321-328Abstract Full Text PDF PubMed Scopus (72) Google Scholar reviewing different steps required on the quest for transplantation, concluded that black patients with ESRD are particularly more likely than white patients with ESRD to “get stuck” at one of these steps (hence, not get listed for a kidney transplant) because of a lack of information and education. Ojo and Port,23Ojo A Port F Influence of race and gender on related donor renal transplantation rates.Am J Kidney Dis. 1993; 22: 835-841PubMed Scopus (56) Google Scholar when referring to the process of pursuing a transplant, described it as a “pathway that an ESRD patient must navigate to the transplant event.”23Ojo A Port F Influence of race and gender on related donor renal transplantation rates.Am J Kidney Dis. 1993; 22: 835-841PubMed Scopus (56) Google Scholar Despite education given to patients by professionals, it may be alternate information received through family or friends that supplements explanations required regarding the benefits and process involved in transplantation. This information may be received through weak social support network ties: a patient with ESRD learns about the process through networking or receiving such information from contacts who are savvy about complex medical procedures and how best to access such treatments. I hypothesize that because of structural aspects of black social networks, their lack of access to weak ties to individuals with particular characteristics (more knowledge about transplantation) may present a barrier (ergo, no bridge) to accessing information about this form of renal replacement therapy. Attributes of African-American social support networks discussed previously may not provide the most comprehensive information regarding such alternate or optimal medical regimens24Belgrave F Psychosocial Aspects of Chronic Illness and Disability Among African Americans. Auburn House, Westport, CT1998Google Scholar as transplantation because it has been shown that African Americans have less knowledge about transplants. This hypothesis is supported by previous literature. The Council on Ethical and Judicial Affairs reported that “other factors…such as education and the skills that come from it, inevitably restrict the ability of some blacks to gain access to and to negotiate effectively for the best medical treatment available.”25Council on Ethical and Judicial Affairs Black-white disparities in health care.JAMA. 1990; 263: 2344-2346Crossref PubMed Scopus (240) Google Scholar Kasiske et al4Kasiske BL London W Ellison MD Race and socioeconomic factors influencing early placement on the kidney transplant waiting list.J Am Soc Nephrol. 1998; 9: 2142-2147PubMed Google Scholar noted that lower transplantation referral rates for pre-ESRD black patients may be attributable to that “patients who are socioeconomically disadvantaged may be less likely to understand the advantages of listing early, and, as a result, may not be good advocates for themselves.”4Kasiske BL London W Ellison MD Race and socioeconomic factors influencing early placement on the kidney transplant waiting list.J Am Soc Nephrol. 1998; 9: 2142-2147PubMed Google Scholar Prottas26Prottas JM Encouraging altruism: Public attitudes and the marketing of organ donation.Milbank Q. 1983; 61: 278-306Crossref Scopus (74) Google Scholar concluded that some portion of lower black organ donation is caused by a “lack of good information.” It has been determined that compared with Caucasians, African Americans have less awareness and knowledge about renal disease, transplantation, and the benefits and success rate of kidney transplantation.5Ozminkowski R White A Hassol A Murphy M Minimizing racial disparity regarding receipt of a cadaver kidney transplant.Am J Kidney Dis. 1997; 30: 749-759Abstract Full Text PDF PubMed Scopus (52) Google Scholar African Americans also have been found to be less likely than whites to know of people who had signed organ donation cards or donated an organ.27Chestang L The policies and politics of health and human services: A black perspective.in: The Black Experience: Considerations for Health and Human Services (15-25). International Dialogue, Davis, CA1983Google Scholar Hence, black Americans have been shown to have a different social conception of transplantation than white Americans. For the purposes of this conceptual foundation about causation for racial disparity in transplantation, getting a kidney transplant may be a social phenomenon potentially dependent on access to information from social networks. Work regarding social network ties and their relationship to employment has dispelled the conception that labor market information is disseminated uniformly in our social structure. Similarly, the long history of racial disparity that confounds the kidney transplantation program may be accounted for by further study regarding social networks of patients with ESRD. Because this is a novel approach to looking at this social problem, much research is needed to validate the use of the social network theory and usefulness of weak ties in regard to kidney transplantation. Therefore, initial research hypotheses and methods include suggestions for future work that would validate this conceptual paradigm. Hypothesis 1: Patients with ESRD who receive information about the transplantation referral and evaluation procedure from contacts and other weak ties in their social network are more likely to pursue such a procedure. Hypothesis 2: Compared with white patients with ESRD, black patients with ESRD are less likely to use weak ties in finding information about kidney transplantation. These hypotheses could be tested either or both quantitatively (surveys of dialysis patients) and qualitatively (in-depth interviews of individual or focus groups of patients with ESRD), examining and comparing outcomes for both white and black patients with ESRD. One necessary step in the research process would be an investigation that links receipt of information about transplantation to an increase in listings and referral for transplantation. Remarkably, a literature review failed to find research methods that included a simple study of patients with ESRD that asks them how they learned about the benefits of and process regarding transplantation. Determining how patients do this and correlating transplantation status and ethnicity with these answers would suggest the validity of my conceptual paradigm, discover whether there is racial disparity in kidney transplantations caused by social network characteristics, and determine appropriate interventions. As Levinsky28Levinsky N Editorial: Quality and equity in dialysis and renal transplantation.N Engl J Med. 1999; 341: 1691-1693Crossref PubMed Scopus (20) Google Scholar (p 1692) states, racially disparate rates of kidney transplantation access are “especially unconscionable in a program paid for largely by the US government.” I provide evidence that reasons purported to date for racial disparities in kidney transplantations (socioeconomic, medical, and patient preference) are not sufficient to explain this variance and a theoretical foundation for an alternate explanation. One solution to this public health crisis may be to examine further the role of weak social support network ties in enhancing information regarding kidney transplantation and intervene accordingly.