Did race/ethnicity disparities in severe COVID-19 outcomes persist in the era of vaccination?

By Pooja Toshniwal PahariaReviewed by Lily Ramsey, LLMMay 5 2023

In a recent study published in the Clinical Infectious Diseases Journal, researchers evaluated whether race/ethnicity disparities in coronavirus disease 2019 (COVID-19) severity outcomes were persistent during the period of COVID-19 vaccine availability.

Study: Vaccination Status and Trends in Adult COVID-19-Associated Hospitalizations by Race and Ethnicity, March 2020—August 2022. Image Credit: Rohane Hamilton/Shutterstock.com

Background

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection-associated hospitalizations and deaths disproportionately impacted ethnic and racial minority groups. During the initial COVID-19 wave (between March 2020 and February of the following year), Hispanics, as well as non-Hispanic American Indians or Alaskan Natives, Blacks, and Asians or Pacific Islanders, had a greater likelihood of having greater rates of admission to hospitals and intensive care units (ICUs), and at-hospital deaths compared to Whites of non-Hispanic ethnicity.

The risk of hospitalization continued to be greater even after adjusting for participant age and the differential comorbidity profiles, as observed during the initial 3.0 months of COVID-19.

However, COVID-19 messenger ribonucleic acid (mRNA) vaccines demonstrated efficacy in preventing SARS-CoV-2 infection severity outcomes, reducing the global health burden of COVID-19.

About the study

In the present study, researchers determined the rate ratios (RRs) for SARS-CoV-2 infection-associated hospital admissions by ethnicity and race between March 2020 and August 2022 to investigate whether ethnic and racial disparities persisted amid the availability of COVID-19 vaccines and the constant circulation of SARS-CoV-2 variant strains.

The team calculated age-adjusted and population-level month-wise rates of SARS-CoV-2 infection-associated hospitalization and RRs by ethnicity and race among adults who participated in the coronavirus disease 2019-associated Hospitalization Surveillance Network (COVID-NET) study between March 2020 and August 2022.

Among patients sampled randomly between July 2021 and August 2022, the RR values for admission to hospitals and intensive care units and at-hospital deaths were determined for Hispanics, Blacks, Asians/Pacific Islanders (API), and American Indians/Alaskan Natives (AI/AN) versus Whites.

The team excluded 10,485 pediatric hospitalizations (3.0%), 17,063 hospitalizations of individuals of unknown race (4.40%), and 1,624 hospitalizations with >one documented race (0.4%).  

In addition, out of 10,228 adults hospitalized between July 2021 and August 2022, individuals with incomplete chart reviews (1.40%), pregnant women (7.0%), individuals who were partially vaccinated (3.90%), or individuals with unknown vaccination status (2.40%) were excluded.

As a result, 8,706 individuals were considered for the final analysis. The COVID-NET study included individuals residing across 99 counties over 14 states of the United States (US), with a SARS-CoV-2-positive result in molecular or rapid SARS-CoV-2 antigen tests at hospitalization or ≤four days before admission.

Data were obtained on the residing state, age, sex, hospitalization date, and the date, type, and findings of SARS-CoV-2 tests. In addition, the COVID-19 vaccination status of hospitalized individuals and vaccine coverage in the catchment areas were ascertained using the state immunization information system (IIS) data.

The incidence rates (among every 100,000 individuals) were calculated based on COVID-NET findings and the National Centre for Health Statistics (NCHS) 2020 population-level estimates.

Results

The data of 353,807 adult hospitalizations showed that hospitalization rates were greater among Hispanics, Blacks, and American Indians/Alaskan Natives than Whites between March 2020 and August 2022.

However, the extent of the discrepancies reduced with time. The RR values for Hispanics in June 2020 and July 2021 were 6.70 and <2.0, respectively. An RR value of 8.40 was observed for American Indians/Alaskan Natives for May 2020, which reduced to below 2.0 following March 2022.

Likewise, the RR value for Blacks was 5.30 in July 2020 and dropped below 2.0 following February 2022. For 8,706 individuals sampled between July 2021 and August 2022, the RR values for hospital and intensive care unit admission were greater for Hispanics, Blacks, and American Indians/Alaskan Natives (ranging from 1.40 to 2.40).

They were lesser for Asians/Pacific Islanders (ranging from 0.60 to 0.90) than Whites. All other ethnicities and races had more in-hospital deaths than Whites (RRs ranging from 1.40 to 2.90).

The monthly age-adjusted hospitalization rates peaked between April and May 2020, December 2020, and January 2022. The rates were greatest for American Indians/Alaskan Natives (161.0 and 288, respectively) during the initial two peaks and for Blacks (278), followed by American Indians/Alaskan Natives (194) during the third peak.

Ethnic and racial discrepancies in SARS-CoV-2 infection-related hospitalization rates persisted between March 2020 and August 2022.

Between July 2021 and August 2022, American Indians/Alaskan Natives, Blacks, and Hispanics had more hospital admissions, intensive care units, and at-hospital deaths than Whites.

Among individuals hospitalized during the period, >50% were unvaccinated, and among unvaccinated Hispanics and American Indians/Alaskan Natives, >50% of the hospital admissions were observed among 18.0-to-49.0-year-olds.

Contrastingly, the greatest fraction of hospitalized and unvaccinated Whites was 65.0 years and above; only 22.0% were aged between 18 and 49 years. There were no race- or ethnicity-based differences in COVID-19 severity outcomes within the vaccination groups.

Conclusion

The study findings showed that ethnic and racial discrepancies in COVID-19-related hospital admissions decreased but persisted during vaccine availability.

Continual outreach to young American Indians/Alaska Natives, Blacks, and Hispanics is required to enhance vaccination coverage, provide equitable access to health services, prevent hospitalizations, and reduce racial and ethnic discrepancies.

The findings could also help identify the individuals that would benefit the most from health initiatives.