Nearly 800,000 patients in the United States have end-stage kidney disease, with more than 550,000 receiving maintenance dialysis (1). Compared to the general population, dialysis patients incur a greater burden of illness, with more comorbid conditions, including diabetes mellitus, hypertension, intrinsic pulmonary disease, cardiovascular and cerebrovascular disease, obesity, and frailty. Individuals dependent on maintenance dialysis are extremely vulnerable to the effects of infection with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2), the virus that causes Coronavirus Disease 2019 (COVID-19), with COVID-associated mortality likely exceeding 20% (2).
In October 2020, the National Academy of Medicine released its plan for vaccination against COVID-19 (3), prioritizing vaccination of healthcare workers, followed by older individuals and those with chronic medical conditions. On December 1, 2020, the Advisory Committee on Immunization Practices of the Centers for Disease Control and Prevention voted to recommend that both healthcare workers and residents of long-term care facilities be first in line for any coronavirus vaccines (4), with the lone dissenting voter expressing concerns that vaccines had not been tested in a long-term care population. The members of the American Society of Nephrology (ASN) COVID-19 Outpatient Dialysis Subcommittee support these recommendations, stressing that: 1) dialysis facility staff must be included with other healthcare workers as priority vaccine recipients, and 2) patients on dialysis should be the next priority after long-term care facility residents, reflecting their limited ability to physically distance, heightened vulnerability to infection, and poor outcomes if infected (2, 5). This is consistent with the position statement of the UK kidney community released on December 4, 2020, indicating highest priority for vaccination for those patients treated by dialysis (6).
With the recognition that physical distancing is not feasible for patients on dialysis, this prioritization not only benefits these individual patients but also myriad personnel who encounter them frequently, including transportation providers and family members who transport patients to and from dialysis facilities and the greater network of healthcare providers who care for these patients in ambulatory and inpatient settings.
While dialysis facilities have performed well in the pandemic, with few described cases of transmission within the facility, hemodialysis facilities remain high-risk settings. We contend that strategic prioritization of patients on dialysis for COVID-19 vaccination will increase safety in dialysis facilities, reducing the risk of infection among patients who are obligatorily congregated during relatively prolonged hemodialysis sessions alongside dialysis workers. While better able to physically distance, home dialysis patients share several risk factors for infection with in-center patients, including frequent healthcare encounters. With clear-eyed recognition of the hazards of the mandatory congregate hemodialysis setting, the dialysis community has modeled excellent practices regarding 2 of the “3 Ws” of “wearing masks,” “washing hands,” and “watching your distance.” The latter remains a challenge while caring for patients congregated within a dialysis facility. From the outset of the pandemic, dialysis facilities rapidly adopted universal intake screenings for fever, symptoms, and exposure(s) to COVID-19. For patients who were identified as having symptoms potentially consistent with COVID-19 and for dialysis patients with COVID-19, dialysis facilities implemented rigorous protocols, including proactive cohorting to provide dialysis separately to patients who were either positive for COVID-19 or under investigation for COVID-19. This often involved creating separate “COVID shifts” or dedicating facilities entirely to the care of hemodialysis patients with COVID-19 (7). These tactics have been largely successful at preventing spread within dialysis facilities.
The best way to maximize dialysis patient safety is to limit exposures to risk. For other infectious diseases, this has been accomplished through proactive campaigns within dialysis facilities to increase patient and staff vaccination rates, including for influenza and hepatitis B viruses, as well as mandatory reporting of dialysis facility staff influenza vaccination in the quality incentive program (8). These lessons, including a focus on both patient and staff vaccination, can be extended to COVID-19, where, to maximize safety, both dialysis staff and dialysis patients must be high priority for vaccination. Patient vaccination will have downstream benefits beyond those to the individual, reflecting that dialysis patients often travel in groups to dialysis units, frequently reside in long-term care facilities, and may have large familial-social networks engaged in their care. Staff vaccination has similar benefits, recognizing that many dialysis staff work at multiple dialysis facilities and hospitals, increasing the number of potential exposures should they have COVID-19.
Prior to the pandemic, maintenance dialysis patients had an annual mortality rate of 18% to 20%, primarily attributable to cardiovascular disease and infectious causes. Per the United States Renal Data System, all-cause mortality has increased dramatically since March 2020, the onset of the COVID-19 pandemic in the United States. For patients receiving maintenance dialysis, mortality was 37% greater during April 2020 compared to the same calendar-weeks of 2017 to 2019; similarly, mortality was also 16% higher in weeks 18 to 27 of 2020 (roughly late April to June). This upsurge of mortality was ascribed to documented SARS-CoV-2 infections, undocumented viral infections, and decreased access to necessary non-dialysis-related medical care (1).
The success of a proposed conjoint strategy of immunizing patients receiving dialysis and associated healthcare workers depends on the immune response of patients on dialysis to vaccines. This is an area of some uncertainty; although data suggest that many dialysis patients do respond to vaccines, patients receiving maintenance dialysis are variably and somewhat unpredictably immunosuppressed. Anergy during tuberculous antigen testing and suboptimal antibody titer generation following a hepatitis B vaccination series or vaccination against influenza viruses are well-documented displays of suboptimally functioning immune systems. T cell and antigen-presenting cell dysfunction are also central to the vulnerability of patients on dialysis. Further, many patients with chronic kidney disease, including those treated with dialysis, are prescribed immunosuppressive medications.
Patients receiving maintenance dialysis have not been enrolled widely in COVID-19 vaccination trials. Initial vaccines will incorporate two technologies. The mRNA vaccines, including those produced by Pfizer and Moderna, instruct patients’ own bodies to manufacture a spike protein that is found on the surface of SARS-CoV-2 that the body then recognizes as foreign and generates an immune response. The goal is for this immune response to be durable. Critically, there is no live or attenuated virus incorporated in this technology, and symptoms associated with vaccination reflect upregulation of the immune response (9). In contrast, other vaccines, such as that from AstraZeneca/Oxford, are more traditional, using a modified adenovirus vector to deliver a COVID-19 spike protein to patients in order to trigger an immune response and antibody development. While there is no reason to expect that vaccine safety for either of these vaccine technologies will differ between dialysis patients and the general population, efficacy remains unknown, and studies are urgently required in dialysis and immunocompromised populations.
Vaccination logistics are critical for dialysis-dependent patients and dialysis staff, and the earliest available mRNA vaccines require ultra-cold storage and repeat vaccination after 3 to 4 weeks. The choice of vaccine for patients receiving dialysis may be critical, with advantages associated with vaccines that only require conventional storage possibly outweighing possible increased efficacy. Critically though, dialysis facilities are uniquely positioned to administer vaccines to this highly vulnerable population at a three- to four-week interval, given the numerous and repeated contacts (thrice weekly for in-center patients and monthly for home patients).
Dialysis facilities are proficient at tracking vaccine administration and infection. Most facilities operate with robust electronic health records, and all are familiar with data reporting to various federal and state monitoring databases. Critically, for patients treated with hemodialysis, where bloodstream access is easy, quality improvement protocols could be implemented to assess vaccine response via serologic testing, with widespread dissemination of results to inform national vaccination strategies. Ultimately, through public data sharing, confidence regarding the safety and efficacy of COVID-19 vaccines would be engendered (10).
As expected, patients receiving dialysis are already presenting their individual preferences and beliefs to their care providers. In this way, they are exactly the same as the general population, only with disproportionately high burdens of fear and anxiety by comparison. Many are eager to be first in line for vaccination, whereas others will wait for safety data to emerge. A minority will likely refuse vaccination, irrespective of such results, with public health needs invariably colliding with the need to maintain patient autonomy. In this situation, it is critical that dialysis facility staff, including the nephrologists, nurses, social workers, and other clinicians who have established relationships with these patients, work with patients to overcome fears and trepidation regarding vaccination. A challenging discussion lies ahead regarding the possibility of mandating vaccination for patients and staff at dialysis facilities.
In sum, patients on dialysis, particularly those receiving maintenance in-center hemodialysis, represent a relatively large population of vulnerable individuals who are obligated to congregate multiple times per week and are at high risk of death should they develop COVID-19. These patients and the healthcare workers who care for them are a priority for immunization. Critically, the immune responses to immunization against SARS-CoV-2 are unknown due to lack of trial data, and, in the absence of rigorous current data, monitoring plans need to be put into place with minimal barriers to evaluate vaccine safety and efficacy. Finally, dialysis providers and the public health community will need to work together to address potential logistic barriers to vaccine administration in dialysis facilities in order to maximize the uptake of vaccines in this vulnerable population.
References
- 1.↑
United States Renal Data System. 2020 USRDS Annual Data Report: Epidemiology of kidney disease in the United States. National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, 2020. https://adr.usrds.org/2020
- 2.↑
Sim JJ, et al.. COVID-19 and survival in maintenance dialysis. Kidney Med [published online ahead of print November 24, 2020]. doi: 10.1016/j.xkme.2020.11.005; https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7685033/
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The National Academies of Sciences, Engineering, and Medicine. National Academies release framework for equitable allocation of a COVID-19 vaccine for adoption by HHS, state, tribal, local, and territorial authorities. Published October 2, 2020. Accessed November 23, 2020. https://www.nationalacademies.org/news/2020/10/national-academies-release-framework-for-equitable-allocation-of-a-covid-19-vaccine-for-adoption-by-hhs-state-tribal-local-and-territorial-authorities
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Centers for Disease Control and Prevention. Advisory Committee on Immunization Practices. December 1, 2020 meeting recommendation. Accessed December 2, 2020. https://www.cdc.gov/vaccines/acip/recommendations.html
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Couchoud C, et al.. Low incidence of SARS-CoV-2, risk factors of mortality and the course of illness in the French national cohort of dialysis patients. Kidney Int 2020; 98:1519−1529. doi: 10.1016/j.kint.2020.07.042
- 6.↑
UK Renal Community. COVID-19 vaccination for adult patients with kidney disease: A position statement from the UK renal community. Published December 4, 2020. Accessed December 4, 2020. https://renal.org/sites/renal.org/files/Renal%20community%20position%20statement%20on%20COVID%2019%20vaccination%20-%204%20Dec%202020.pdf
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Kliger AS, Silberzweig J. Mitigating risk of COVID-19 in dialysis facilities. Clin J Am Soc Nephrol 2020; 15:707−709. doi: 10.2215/CJN.03340320
- 8.↑
Krueger KM, et al.. Practical guide to vaccination in all stages of CKD, including patients treated by dialysis or kidney transplantation. Am J Kidney Dis 2020; 75:417−425. doi: 10.1053/j.ajkd.2019.06.014
- 9.↑
Centers for Disease Control and Prevention. Understanding mRNA COVID-19 vaccines. Accessed December 4, 2020. https://www.cdc.gov/coronavirus/2019-ncov/vaccines/different-vaccines/mrna.html
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Lurie N, Experton B. How to leverage the Medicare program for a COVID-19 vaccination campaign. JAMA [published online ahead of print November 19, 2020]. doi: 10.1001/jama.2020.22720; https://jamanetwork.com/journals/jama/fullarticle/2773348