OP84 Evaluating the impact of the national vaccination programme in England on inequalities in COVID-19 mortality: an ecological study

Background

The effectiveness of vaccination against severe COVID-19 infection and mortality is well documented, but there are inequalities in both vaccination uptake and COVID-19 mortality. Understanding whether more equal vaccination uptake might reduce socioeconomic inequalities in COVID-19 mortality is necessary for planning for future pandemics. Limited evidence available suggests that COVID-19 vaccination may have reduced inequalities in mortality. However, existing studies employ data covering a short time frame, meaning the effects of population-wide full vaccination uptake have yet to be studied. We aimed to investigate if the national vaccination program reduced inequalities in COVID-19 mortality associated with area-level deprivation, from the first recorded deaths to December 2022.

Methods

In this ecological study, COVID-19 vaccination (12/2020 – 12/2022) and mortality within 28-days of a positive COVID-19 test (03/2020 – 12/2022) data for England were accessed from Coronavirus.data.gov. Age-standardised mortality rates were estimated from age-stratified regional data according to Lower Tier Local Authority (LTLA) age structure and assessed for reliability against the known total mortality for each LTLA. Cumulative vaccination uptake by LTLA for each dose was also calculated. LTLAs were assigned to a quintile of the Index of Multiple Deprivation. A generalised linear mixed model was used, with relative inequality in mortality (the least to the most deprived quintiles) operationalised in log form, and underlying COVID-19 mortality rate and vaccination in the most and least deprived quintiles also included. Sensitivity analyses were performed to assess the possible impact of the changing testing availability on our outcome measure.

Results

The average proportion vaccinated at the end of 2022 for vaccination one was 73.7% in the most deprived and 81.6% in the least, 69.6% and 79.1% respectively for vaccination two, and for 52.2% and 66.8% respectively for vaccination three. Descriptive analyses demonstrated that inequalities in mortality gradually decreased after the third lockdown, continued to decline as vaccination uptake and doses increased, and remained low throughout 2022. Despite increasing vaccination uptake over time and by dose, some inequalities in mortality and vaccination uptake by area deprivation remained.

Discussion

This study provides evidence that the COVID-19 vaccine was associated with reduced inequalities in mortality 28-days after a positive COVID-19 test. More equitable vaccine uptake may have reduced deprivation-based inequalities in mortality even further. Research suggests the outcome measure we employ slightly overestimates deaths from COVID-19. However, due to identification risks, data on deaths with COVID-19 on the certificate are not available at LTLA level due to identification risks.