Geographic Variation in Influenza Vaccination Disparities Between Hispanic and Non-Hispanic White US Nursing Home Residents

Abstract

Background Disparities in influenza vaccination exist between Hispanic and non-Hispanic White U.S. nursing home (NH) residents, but the geographic areas with the largest disparities remain unknown. We examined how these racial/ethnic disparities differ across states and hospital referral regions (HRRs). Methods This retrospective cohort study included >14 million short-stay and long-stay U.S. NH resident-seasons over seven influenza seasons from October 1, 2011 to March 31, 2018, where residents could contribute to one or more season. Residents were aged ≥65 years and enrolled in Medicare fee-for-service. We used the Medicare Beneficiary Summary File to ascertain race/ethnicity and Minimum Data Set assessments for influenza vaccination. We calculated age- and sex-standardized percentage point (pp) differences in the proportions vaccinated between non-Hispanic White and Hispanic (any race) resident-seasons. Positive pp differences were considered to be disparities, where the proportion of non-Hispanic White residents vaccinated was greater than the proportion of Hispanic residents vaccinated. States and HRRs with ≥100 resident-seasons per age-sex stratum per racial/ethnic group were included in analyses. Results Among 7,442,241 short-stay resident-seasons (94.1% non-Hispanic White, 5.9% Hispanic), the median standardized disparities in influenza vaccination were 4.3 pp (minimum, maximum: 0.3, 19.2; n = 22 states) and 2.8 pp (minimum, maximum: -3.6, 10.3; n = 49 HRRs). Among 6,758,616 long-stay resident-seasons (93.7% non-Hispanic White, 6.5% Hispanic), the median standardized differences were -0.1 pp (minimum, maximum: -4.1, 11.4; n = 18 states) and -1.8 pp (minimum, maximum: -6.5, 7.6; n = 34 HRRs). Conclusions Wide geographic variation in influenza vaccination disparities existed across U.S. states and HRRs. Localized interventions targeted towards areas with high disparities may be a more effective strategy to promote health equity than one-size-fits-all national interventions.