A Randomized-Intervention Trial to Test the Efficacy of a Low Intensity Strategy to Improve Hypertension Medication Adherence among Adults with Intellectual Disability Living at Home

Suzanne McDermott, PhD, University of South Carolina (4 year project, Funded 2017)

This study was designed in response to findings from our analysis of South Carolina Medicaid data, which investigated the prescription filling practices of adults with Intellectual and Developmental Disability (IDD) who had a medical diagnosis of hypertension and lived in the community with parents or caregivers. The previous study was limited to individuals who were newly prescribed to begin taking hypertension medication during the study period.1 We were able to link pharmacy files with individual Medicaid recipient files, and we learned that less than half (~49.5%) of the study cohort had ≥80% of prescription days covered (PDC), and were thus considered adherent to anti-hypertensive medication. The study cohort was comprised of 1573 members with IDD and hypertension, who were 22-64 years of age, and medication adherence was defined as being in possession of enough prescription medication to cover at least 80% of the days until the next refill was due. Using multivariable analyses, we found that adults in the cohort who lived in group homes or community supported living had four times the odds of those who lived at home (OR: 4.049, 95% CI: 2.670, 6.140) to be adherent to anti-hypertensive medication. Individuals who lived at home were in the highest risk group for having an inadequate supply of hypertensive medication.

The over-arching aim for this study is to test the efficacy of a low intensity caregiver intervention to increase hypertension medication adherence, compared to usual care. The hypotheses all pertain to individuals with IDD, who have a diagnosis of hypertension, and who live at home with their parent(s) or caregivers:

  • Case group individuals will have 10% more days PDC, six months after the intervention ends, compared to Comparison group individuals.
  • The scores of Case parents/caregivers on the survey regarding knowledge of hypertension will increase by 20% from pre- to post-intervention, compared to no change in the Comparison parents/caregivers.
  • Comparison group individuals will have an average of at least one additional Emergency
    Department or Inpatient visit for issues related to hypertension and its sequella, as compared to the Case group, in the one-year period after the intervention ends.

*Stevens AC, Royer J, Carroll DD, Courtney-Long EA, McDermott S, Turk MA. (2018) Anti-hypertensive medication use and factors related to adherence among adults with intellectual disability in South Carolina. American Journal of Intellectual and Developmental Disabilities. In Press.