Original Article

Discrepancies in Outcomes by Race and Ethnicity in COVID-19 Patients Receiving Casirivimab and Imdevimab

Authors: Tony Zitek, MD, Joseph Bui, BS, Alyssa Eily, MD, David A. Farcy, MD


Objectives: The Centers for Disease Control and Prevention has reported increased rates of coronavirus disease 2019 (COVID-19)–related hospitalizations and deaths in Black and Hispanic individuals. One contributing factor to this may be a difference in access to treatment. We thus sought to compare the outcomes of Black, non-Hispanic patients and Hispanic patients with White, non-Hispanic individuals using a group of patients with COVID-19 who received casirivimab/imdevimab.

Methods: This was a secondary analysis of data from a previously published retrospective chart review of patients who received casirivimab/imdevimab for COVID-19 between December 9, 2020 and August 20, 2021, when they were treated at one of three facilities within a single hospital system. We compared the baseline characteristics (including age, sex, body mass index, duration of symptoms, and vaccination status) and outcomes of Black, non-Hispanic patients and Hispanic patients with those of White, non-Hispanic patients. Our primary outcome was the odds of a return visit to the emergency department (ED) within 28 days of treatment as assessed by multivariate logistic regression. We also assessed the rates of return visits to the ED for symptoms caused by COVID-19, hospitalizations, and hospitalizations from hypoxia.

Results: In total, 1318 patients received casirivimab/imdevimab for COVID-19 at the three study facilities. Of these, 410 (31.1%) identified themselves as White and non-Hispanic, 88 (6.7%) as Black and non-Hispanic, and 736 (55.8%) as Hispanic. Vaccination rates at the time of treatment were as follows: Black, non-Hispanic 10.2%, Hispanic 13.6%, and White, non-Hispanic 21.5%. On multivariate analysis, the odds of return visits to the ED within 28 days were higher for Black, non-Hispanic patients and Hispanic patients as compared with White, non-Hispanic patients, with odds ratios of 2.8 (95% confidence interval [CI] 1.4–5.5, P = 0.003) and of 2.3 (95% CI 1.5–3.6, P = 0.0002), respectively. For hospitalizations caused by hypoxia within 28 days of treatment, the adjusted odds ratio for Black, non-Hispanic patients was 3.4 (95% CI 1.1–10.5, P = 0.03) as compared with White, non-Hispanic patients. There were no other statistically significant differences among groups in regard to subsequent hospitalizations within 28 days.

Conclusions: Black, non-Hispanic patients and Hispanic patients are more likely to make a return visit to the ED within 28 days after casirivimab/imdevimab treatment for COVID-19 as compared with White, non-Hispanic patients. This holds true even when adjusting for higher vaccination rates among White, non-Hispanic individuals.
Posted in: Infectious Disease103

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1. Congressional Research Service. COVID-19: US economic effects, May 13, 2020; https://crsreports.congress.gov/product/pdf/IN/IN11388. Accessed November 20, 2021.
2. O’Neil SS, Lake T, Merrill A, et al. Racial disparities in hospitalizations for ambulatory care–sensitive conditions. Am J Prev Med 2010;38:381–388.
3. Price-Haywood EG, Burton J, Fort D, et al. Hospitalization and mortality among Black patients and White patients with Covid-19. N Engl J Med 2020;382:2534–2543.
4. Holtgrave DR, Barranco MA, Tesoriero JM, et al. Assessing racial and ethnic disparities using a COVID-19 outcomes continuum for New York state. Ann Epidemiol 2020;48:9–14.
5. Centers for Disease Control and Prevention. Risk for COVID-19 infection, hospitalization, and death by race/ethnicity. https://www.cdc.gov/coronavirus/2019-ncov/covid-data/investigations-discovery/hospitalization-death-by-race-ethnicity.html. Accessed November 20, 2021.
6. Poulson M, Geary A, Annesi C, et al. National disparities in COVID-19 outcomes between Black and White Americans. J Natl Med Assoc 2021;113:125–132.
7. Moore JT, Ricaldi JN, Rose CE, et al. Disparities in incidence of COVID-19 among underrepresented racial/ethnic groups in counties identified as hotspots during June 5-18, 2020—22 states, February-June 2020. MMWR Morb Mortal Wkly Rep 2020;69:1122–1126.
8. Platt L, Warwick R. Are some ethnic groups more vulnerable to COVID-19 than others? https://ifs.org.uk/inequality/chapter/are-some-ethnic-groups-more-vulnerable-to-covid-19-than-others/. Published May 1, 2020. Accessed November 20, 2021.
9. Richardson LD, Norris M. Access to health and health care: how race and ethnicity matter. Mt Sinai J Med 2010;77:166–177.
10. Gaskin DJ, Dinwiddie GY, Chan KS, et al. Residential segregation and the availability of primary care physicians. Health Serv Res 2012;47:2353–2376.
11. Chan KS, Gaskin DJ, McCleary RR, et al. Availability of health care provider offices and facilities in minority and integrated communities in the US. J Health Care Poor Underserved 2019;30:986–1000.
12. Guadamuz JS, Wilder JR, Mouslim MC, et al. Fewer pharmacies in black and Hispanic/Latino neighborhoods compared with white or diverse neighborhoods, 2007-15. Health Aff 2021;40:802–811.
13. Buikema AR, Buzinec P, Paudel ML, et al. Racial and ethnic disparity in clinical outcomes among patients with confirmed COVID-19 infection in a large US electronic health record database. EClinicalMedicine 2021;39: 101075.
14. Roberts JD, Dickinson KL, Koebele E, et al. Clinicians, cooks, and cashiers: examining health equity and the COVID-19 risks to essential workers. Toxicol Ind Health 2020;36:689–702.
15. Hawkins D. Differential occupational risk for COVID-19 and other infection exposure according to race and ethnicity. Am J Ind Med 2020;63:817–820.
16. Zitek T, Jodoin K, Kheradia T, et al. Vaccinated patients have reduced rates of hospitalization after receiving casirivimab and imdevimab for COVID-19. Am J Emerg Med 2022;56:370–371.
17. US Food and Drug Administration. Fact sheet for health care providers emergency use authorization (EUA) of REGEN-COVTM (casirivimab with imdevimab). https://www.fda.gov/media/145611/download. Accessed September 15, 2021.
18. Becerra-Muñoz VM, Núñez-Gil IJ, Maroun Eid C, et al. Clinical profile and predictors of in-hospital mortality among older patients hospitalised for COVID-19. Age Ageing 2021;50:326–334.
19. Rod JE, Oviedo-Trespalacios O, Cortes-Ramirez J. A brief–review of the risk factors for covid-19 severity. Rev Saude Publica 2020;54:60.
20. Malik P, Patel U, Patel K, et al. Obesity a predictor of outcomes of COVID-19 hospitalized patients. A systematic review and meta-analysis. J Med Virol 2021;93:1188–1193.
21. O’Horo J, Challener DW, Anderson RJ, et al. Rates of severe outcomes after bamlanivimab-etesevimab and casirivimab-imdevimab treatment of high-risk patients with mild to moderate coronavirus disease 2019. Mayo Clin Proc 2022;97:943–950.
22. Miech RA, Hauser RM. Socioeconomic status and health at midlife. A comparison of educational attainment with occupation-based indicators. Ann Epidemiol 2001;11:75–84.
23. Ganesh R, Philpot LM, Bierle DM, et al. Real-world clinical outcomes of bamlanivimab and casirivimab-imdevimab among high-risk patients with mild to moderate coronavirus disease 2019. J Infect Dis 2021;224: 1278–1286.
24. Contreras G, Lenz O, Pardo V, et al. Outcomes in African Americans and Hispanics with lupus nephritis. Kidney Int 2006;69:1846–1851.
25. Goodman SM, Parks ML, McHugh K, et al. Disparities in outcomes for African Americans and Whites undergoing total knee arthroplasty: a systematic literature review. J Rheumatol 2016;43:765–770.
26. Farley J, Risinger JI, Rose GS, et al. Racial disparities in blacks with gynecologic cancers. Cancer 2007;110:234–243.
27. Lewis VA, Fraze T, Fisher ES, et al. ACOs serving high proportions of racial and ethnic minorities lag in quality performance. Health Aff (Millwood) 2017;36:57–66.
28. Webb Hooper M, Mitchell C, Marshall VJ, et al. Understanding multilevel factors related to urban community trust in healthcare and research. Int J Environ Res Public Health 2019;16:3280.
29. Powell W, Richmond J, Mohottige D, et al. Medical mistrust, racism, and delays in preventive health screening among African-American men. Behav Med 2019;45:102–117.
30. Alsan M, Stantcheva S, Yang D, et al. Disparities in coronavirus 2019 reported incidence, knowledge, and behavior among US adults. JAMA Netw Open 2020;3:e2012403.
31. Brown LL, Mitchell UA, Ailshire JA. Disentangling the stress process: race/ethnic differences in the exposure and appraisal of chronic stressors among older adults. J Gerontol B Psychol Sci Soc Sci 2020;75:650–660.