Disparities in COVID-19 vaccination receipt by race, ethnicity, and social determinants of health among a large patient population in a network of community-based healthcare centers

Background: There are known disparities in U.S. COVID-19 vaccination but there is limited information on national vaccine uptake in a large, racially diverse, all-age population. Here, we describe COVID-19 vaccination coverage in a large U.S. population accessing care in OCHIN (not an acronym), a national network of communitybased healthcare organizations. Methods: Within OCHIN, we identified patients aged 6 months and older with >= 1 completed clinical encounter since becoming age-eligible for the COVID-19 vaccine between December 13, 2020 and December 31, 2022. Patients' COVID-19 vaccination status was assessed from OCHIN's Epic (R) electronic health record which includes data from state immunization information systems. Patients were considered vaccinated if they received >= 1 dose of a monovalent vaccine product; coverage was categorized by age groups (6 months-4 years; 5-11 years, 12-15 years, 16+ years). Multivariate analyses assessed factors associated with COVID-19 vaccination across age groups. Results: The cohort included 3.3 million Hispanic (37 %), non-Hispanic (NH) White (31 %), NH Black (15 %), and NH Asian (7 %) patients; 45 % of whom were Medicaid-enrolled, 19 % uninsured, and 53 % with a household income below 100% of the federal poverty level. The proportion with >= 1 COVID-19 vaccine dose increased with age, from 11.7 % (6 months through 4 years) to 72.3 % (65 years and older). The only factors associated with significantly higher COVID-19 vaccine coverage across age groups were prior receipt of an influenza vaccine and having private insurance. In adjusted modeling, when compared to NH whites, COVID-19 vaccine coverage was significantly higher among Hispanic, NH Asian, and NH multiple-race patients aged >= 5 years and significantly lower among NH Black and NH Native Hawaiian/Other Pacific Islander patients aged 6 months-4 years old. Conclusions: We identified disparities in primary series COVID-19 vaccine coverage by age, race and ethnicity, household income, insurance status, and prior influenza vaccination within this large, diverse population accessing care in community-based healthcare organizations.