Snap participation and medication adherence among older black medicaid-insured individuals living with hypertension

BACKGROUND: Black people are more likely to be diagnosed with hypertension and to experience food insecurity and antihypertensive medication non-adherence compared to White people in the U.S. The Supplemental Nutrition Assistance Program (SNAP) - a means-tested program that targets food insecurity has been shown to affect health outcomes. This study analyzed the relationship between SNAP participation and antihypertensive medication adherence among older Black Medicaid-insured individuals. METHODS: This is a retrospective cohort study using linked 2006-2014 state of Missouri Medicaid and SNAP administrative claims data. Analyses were restricted to older (≥60 years) Black individuals who were continuously enrolled in Medicaid for 12 months following their first observed claim for hypertension at or after age 60 years with at least one pharmacy claim (n=10,693). Our outcome measure is a dichotomous measure of antihypertensive medication adherence defined using the Proportion of Days Covered (≥80% PDC=1). The exposure variables are four measures of SNAP participation. RESULTS: A higher proportion of SNAP participants were adherent to their antihypertensive medications compared to non-SNAP participants (43.5% vs. 32.0%). On multivariable analyses, compared to non-SNAP participants there was an increased likelihood of antihypertensive medication adherence among SNAP participants (prevalence ratio [PR]=1.25; 95% confidence interval [CI]=1.16-1.35). Compared to those who participated in SNAP for 1-3 months during the 12-month continuous enrollment, there was an increased likelihood of antihypertensive medication adherence among those who were enrolled for 10-12 months (PR=1.41; 95% CI=1.08-1.85). CONCLUSIONS: Medicaid-insured older Black adults who were SNAP participants had a higher likelihood of antihypertensive medication adherence compared to non-SNAP participants.