ImportanceThe people of Hawaiʻi have both high rates of health insurance and high levels of racial and ethnic diversity, but the degree to which insurance status and race and ethnicity contribute to health outcomes in COVID-19 remains unknown.ObjectiveTo evaluate the associations of insurance coverage, race and ethnicity (using disaggregated race and ethnicity data), and vaccination with outcomes for COVID-19 hospitalization.Design, Setting, and ParticipantsThis retrospective cohort study included hospitalized patients at a tertiary care medical center between March 2020 and March 2022. All patients hospitalized for acute COVID-19, identified based on diagnosis code or positive results on polymerase chain reaction–based assay for SARS-CoV-2, were included in analysis. Data were analyzed from May 2022 to May 2023.ExposureCOVID-19 requiring hospitalization.Main Outcome and MeasuresElectronic medical record data were collected for all patients. Associations among race and ethnicity, insurance coverage, receipt of at least 1 COVID-19 vaccine, intensive care unit (ICU) transfer, in-hospital mortality, and COVID-19 variant wave (pre-Delta vs Delta and Omicron) were assessed using adjusted multivariable logistic regression.ResultsA total of 1176 patients (median [IQR] age of 58 [41-71] years; 630 [54%] male) were hospitalized with COVID-19, with a median (IQR) body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) of 30 (25-36) and Sequential Organ Failure Assessment score of 1 (0-2). The sample included 16 American Indian or Alaska Native patients, 439 Asian (not otherwise specified) patients, 15 Black patients, 66 Chinese patients, 246 Filipino patients, 76 Hispanic patients, 107 Japanese patients, 10 Korean patients, 299 Native Hawaiian patients, 523 Pacific Islander (not otherwise specified) patients, 156 Samoan patients, 5 Vietnamese patients, and 311 White patients (patients were able to identify as >1 race or ethnicity). When adjusting for age, BMI, sex, medical comorbidities, and socioeconomic neighborhood status, there were no differences in either ICU transfer (eg, Medicare vs commercial insurance: odds ratio [OR], 0.84; 95% CI, 0.43-1.64) or in-hospital mortality (eg, Medicare vs commercial insurance: OR, 0.85; 95% CI, 0.36-2.03) as a function of insurance type. Disaggregation of race and ethnicity revealed that Filipino patients were more likely to die in the hospital (OR, 1.79; 95% CI, 1.04-3.03; P = .03). When considering variant waves, mortality among Filipino patients was highest during the pre-Delta time period (OR, 2.72; 95% CI, 1.02-7.14; P = .04), when mortality among Japanese patients was lowest (OR, 0.19; 95% CI, 0.03-0.78; P = .04); mortality among Native Hawaiian patients was lowest during the Delta and Omicron period (OR, 0.35; 95% CI, 0.13-0.79; P = .02). Patients with Medicare, compared with those with commercial insurance, were more likely to have received at least 1 COVID-19 vaccine (OR, 1.85; 95% CI, 1.07-3.21; P = .03), but all patients, regardless of insurance type, who received at least 1 COVID-19 vaccine had reduced ICU admission (OR, 0.40; 95% CI, 0.21-0.70; P = .002) and in-hospital mortality (OR, 0.42; 95% CI, 0.21-0.79; P = .01).Conclusions and RelevanceIn this cohort study of hospitalized patients with COVID-19, those with government-funded insurance coverage (Medicare or Medicaid) had similar outcomes compared with patients with commercial insurance, regardless of race or ethnicity. Disaggregation of race and ethnicity analysis revealed substantial outcome disparities and suggests opportunities for further study of the drivers underlying such disparities. Additionally, these findings illustrate that vaccination remains a critical tool to protect patients from COVID-19 mortality.