(650) Are Social Determinants of Health Associated with Vaccine Uptake during Pregnancy?

Social determinants of health (SDOH) are increasingly recognized as critical to vaccine uptake. Therefore, we sought to evaluate the association of socioeconomic deprivation, measured through area deprivation indices (ADIs), with the uptake of the four recommended vaccinations in pregnancy: tetanus-diptheria-acellular pertussis (Tdap), Influenza, coronavirus-19 (COVID), and respiratory syncytial virus (RSV) vaccines.

Study Design:

This was a retrospective observational study among pregnant patients in a large, urban medical system. Patients were included if they were between 32 and 36 weeks’ gestation during the study period – hence eligible for all vaccinations. Exclusion criteria included documented allergy to prior vaccination or pregnancy affected by a lethal fetal anomaly. Relative socioeconomic conditions of patients were defined using ADI, whereby, on a scale of 1 to 10, a higher score  indicates a more deprived area, and a lower score indicates a more affluent area.  Vaccination rates and ADI were abstracted from the electronic medical record and quality checked for accuracy. Kruskal-Wallis testing with post-hoc analyses (Dunn’s test with Bonferroni correction) was performed to determine statistical significance among groups.

Results:
545 individuals met inclusion criteria. The median age of patients included was 33.9 (30.4 to 37.2). 38.7% were obese, and  44%  self-identified as  non-Hispanic Black (Table 1). The median ADI across the study population was 4. Statistically significant differences were observed across all combinations of vaccine uptake (p< 0.001, ***), with post-hoc analyses most notable for a higher ADI in patients receiving Tdap as compared to patients accepting all four vaccines (p< 0.001, ***; Figure 1).

Conclusion:
ADI is significantly associated with the types and numbers of vaccines patients receive in pregnancy, with a general trend toward higher ADI in groups receiving no vaccines and lower ADI in groups receiving all or most vaccines. Complementary qualitative or mixed methods studies will further elucidate barriers to vaccine uptake and motivate appropriate interventions.