Racial Disparities in Health: A Closer Look at End-Stage Renal Disease
By Sonnet Xu, Troy High School, Troy, Michigan, USA
In the United States, black patients are historically known to suffer more disparities when seeking medical treatment. They are much more likely to be of lower socioeconomic status (SES), which adversely impacts their treatment outcomes as higher SES is associated with improved health in the United States and abroad (Kimmel et al., 2013). Unequal distribution of wealth is also associated with higher mortality, a trend seen in black populations.
Along with the SES-related health disparities that black patients often face, they are also more burdened by certain conditions such as End Stage Renal Disease (ESRD). ESRD is defined as an irreversible regression in kidney function that is severe enough to require dialysis or a kidney transplant and is often a progression from chronic kidney disease. While black populations comprise only around 13% of the United States population, they make up over 30% of patients with ESRD in the United States. The relative incidence of ESRD is 3.6 times higher in black than white patients (Kucirka et al., 2011). Black patients often have worse quality of care and tend to not see nephrologists despite their chronic kidney disease. They also have significantly lower rates of referral for kidney transplantation, although it is the preferred method of ESRD treatment (Epstein et al., 2000). Particularly with kidney transplantation, the significant disparities have been repeatedly noted. Black patients are less likely to be identified as kidney transplant candidates, be referred for transplant evaluation, complete the evaluation, or be placed on the waiting list than white patients. Once on the waiting list, black patients wait longer, and may be more likely to receive kidneys from black donors who have APOL1 variants, which are disease variants with increased risk for kidney disease development and thus are more likely to fail (Norton et al., 2016). As a result of this, black transplant recipients have poorer graft survival as early as one year after transplantation than white patients with both deceased and living donor kidneys (Ng et al., 2009).
The combination of the overall impact of SES, genetic predisposition, and lower quality care creates a very negative experience for black patients pursuing and undergoing treatment. In seeking medical care, black patients reported a 25% longer time burden than white patients, despite reporting less time spent with clinicians. Nationally, black individuals were less likely than whites to have had a healthcare visit over the prior year (Norton et al., 2016).
Due to these factors, black patients of the general population have lower life expectancies compared to white patients. Younger black patients have almost double the risk of death than their white counterparts in ESRD treatment (Kucirka et al., 2011). A speculated cause of this large difference in survival is related to insurance coverage, as young black patients often have less access to insurance and are thus less likely to be insured. Lack of insurance leads to poorer and less inaccessible healthcare, which could be a major contributing factor to earlier deaths.
Surprisingly, black patients with ESRD that are over 50 years of age actually have a survival advantage over white populations of similar status who are undergoing hemodialysis. This seemingly paradoxical finding has not been fully explained by economic, societal, or biochemical factors. It is particularly surprising because black patients have higher rates of obesity and overweight than the general population (Lincoln et al., 2016). This finding has been supported by over 30 past studies and is extremely robust. Lower income, income disparity, worse quality care, and segregation are all related to increased mortality, and this is especially prevalent in the black populations (Kimmel et al., 2013). The reasons for survival advantage in the older group of hemodialysis patients have not yet been elucidated. It may be because of treatment adversities that the black population regularly faces, that the older patient group that is left is of comparatively better general fitness. It could also be due to a phenomenon called the obesity paradox, in which patients with higher BMIs and are over-nourished live longer on treatment.
This topic, and the underlying issue of health disparities, is something that needs to be tackled. Especially since ESRD has such a large prevalence among black communities, the inequities they face represent a widespread unfairness to treatment equality. Current interventions should be targeted to this population, particularly towards the younger patients. Focusing on providing optimal treatment to these patients, with increasing the availability of live kidney transplants, would create a very positive impact. Further illuminating the causes that drive the disparities will also offer more opportunities to have better treatments for everyone. As ESRD incidence dramatically rises, it is important to keep a strong focus on making treatment more equitable and accessible.
Batsis, J. A., & Zagaria, A. B. (2018). Addressing Obesity in Aging Patients. Medical Clinics of North America, 102(1), 65–85. https://doi.org/10.1016/j.mcna.2017.08.007
Braveman, P. A., Cubbin, C., Egerter, S., Williams, D. R., & Pamuk, E. (2010). Socioeconomic disparities in health in the United States: what the patterns tell us. American journal of public health, 100 Suppl 1(Suppl 1), S186–S196. https://doi.org/10.2105/AJPH.2009.166082
Epstein, A. M., Ayanian, J. Z., Keogh, J. H., Noonan, S. J., Armistead, N., Cleary, P. D., Weissman, J. S., David-Kasdan, J. A., Carlson, D., Fuller, J., Marsh, D., & Conti, R. M. (2000). Racial disparities in access to renal transplantation--clinically appropriate or due to underuse or overuse?. The New England journal of medicine, 343(21), 1537. https://doi.org/10.1056/NEJM200011233432106
Kimmel, P. L., Fwu, C. W., & Eggers, P. W. (2013). Segregation, Income Disparities, and Survival in Hemodialysis Patients. Journal of the American Society of Nephrology, 24(2), 293–301. https://doi.org/10.1681/asn.2012070659
Kucirka, L. M., Grams, M. E., Lessler, J., Hall, E. C., James, N., Massie, A. B., Montgomery, R. A., & Segev, D. L. (2011). Association of Race and Age With Survival Among Patients Undergoing Dialysis. JAMA, 306(6). https://doi.org/10.1001/jama.2011.1127
Lincoln, K. D., Abdou, C. M., & Lloyd, D. (2014). Race and Socioeconomic Differences in Obesity and Depression among Black and Non-Hispanic White Americans. Journal of Health Care for the Poor and Underserved, 25(1), 257–275. https://doi.org/10.1353/hpu.2014.0038
Ng, F. L., Holt, D. W., Chang, R. W. S., & MacPhee, I. A. M. (2009). Black renal transplant recipients have poorer long-term graft survival than CYP3A5 expressers from other ethnic groups. Nephrology Dialysis Transplantation, 25(2), 628–634. https://doi.org/10.1093/ndt/gfp530
Nuru-Jeter, A. M., Williams, C. T., & LaVeist, T. A. (2014). Distinguishing the Race-Specific Effects of Income Inequality and Mortality in U.S. Metropolitan Areas. International Journal of Health Services, 44(3), 435–456. https://doi.org/10.2190/hs.44.3.b
Ward, J. L., & Viner, R. M. (2017). The Impact of Income Inequality and National Wealth on Child and Adolescent Mortality in Low and Middle-Income Countries. Journal of Adolescent Health, 60(2), S30. https://doi.org/10.1016/j.jadohealth.2016.10.077
CKD - Chronic kidney disease. (2018, September 10). [Photograph]. Wikimedia. https://upload.wikimedia.org/wikipedia/commons/0/0b/CKD_-_Chronic_kidney_disease.jpg