Predictors of Antenatal Seasonal Influenza Vaccination in an Underserved Population [15C

Abstract

INTRODUCTION: Uptake of seasonal influenza vaccination among pregnant women remains low despite recommendations supporting routine vaccination in this population at high risk for severe morbidity. We evaluated predictors of antenatal influenza vaccination in an underserved patient population. METHODS: We conducted a retrospective cohort study of all women with deliveries to Emory healthcare providers at Grady Memorial Hospital, a large safety-net hospital, between July 1, 2016 and June 30, 2018. Demographic and clinical characteristics were abstracted from electronic medical records. The Kotelchuk Index was used to assess prenatal care adequacy. Adjusted relative risks (aRRs) and 95% confidence intervals (CIs) for associations between demographic and clinical characteristics and receipt of influenza vaccine were calculated using multivariable log-binomial models. IRB approval was obtained for this study. RESULTS: Among 3,727 women with deliveries, most were non-Hispanic black (68.60%) and had Medicaid as their primary insurer for delivery (87.93%). The overall vaccination rate was 49.80% (1,856/3,727). Characteristics significantly associated with influenza vaccination in multivariable models were Hispanic ethnicity (aRR 1.44, 95% CI 1.11-1.88), transferring care between institutions (aRR 0.34, 95% CI, 0.29-0.41), and inadequate prenatal care (aRR 0.70, 95% CI, 0.64-0.75). CONCLUSION: Women with inadequate or discontinuous prenatal care were less likely than women with adequate prenatal care to receive a seasonal influenza vaccine. Hispanic ethnicity was associated with increased rates of influenza vaccination, even after controlling for interpretive language services. These findings highlight the importance of continuous, regular prenatal care in recommending and offering antenatal vaccinations to pregnant patients while supporting possible cultural differences in vaccine acceptance.