Lancet

Americans without health insurance were disproportionately affected by COVID-19--Study

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In our analysis of over 26 million cases, we estimated the impact of insurance coverage on COVID-19 mortality using daily individual-level data on COVID-19 cases, hospitalization, and mortality, as well as the delay between symptom onset and COVID-19 test results. Data were aggregated by state, gender, race, and age, and matched with demographic controls and health insurance coverage rates.

We find that nearly 60,000 excess deaths from COVID-19, over 220,000 additional hospitalizations, and 2.9 million additional cases are associated with lack of health insurance. We also find that, prior to emergency appropriations that were enacted to cover the costs of testing, insurance coverage is associated with prompter testing following symptom onset during the initial phase of the pandemic.

Further, we explored the effect of Medicaid expansion on COVID-19 outcomes, comparing counties across state lines. We find that the impact of being in a state with Medicaid expansion compared to an adjacent country in a state without Medicaid expansion is consistent with our national-level findings regarding the effect of health insurance coverage. ...