Disparities in CD4+ T-Lymphocyte Monitoring Among Human Immunodeficiency Virus-Positive Medicaid Beneficiaries: Evidence of Differential Treatment at the Point of Care.

Background: Monitoring of immune function, measured by CD4 cell count, is an essential service for people with Human Immunodeficiency Virus (HIV). Prescription of antiretroviral (ARV) medications is contingent on CD4 cell count; patients without regular CD4 monitoring are unlikely to receive ARVs when indicated. This study assesses disparities in CD4 monitoring among HIV-positive Medicaid beneficiaries.

Methods: In this retrospective observational study, we examined 24 months of administrative data on 2,250 HIV-positive, continuously-enrolled fee-for-service Medicaid beneficiaries with at least two outpatient healthcare encounters. We used logistic regression to evaluate the association of patient demographics (age, gender, race/ethnicity, and language) with receipt of at least one CD4 test per year, controlling for other potentially confounding variables.

Results: Having a history of ARV therapy was positively associated with receipt of CD4 tests. We found racial/ethnic, gender, and age disparities in CD4 testing. Among individuals with a history of ARV use, all racial/ethnic groups were significantly less likely to have CD4 tests than White non-Latinos (African Americans, OR = 0.35, p<0.0001; Asian/Pacific Islanders, OR = 0.31, p=0.0047; and, Latinos, OR = 0.42, p<0.0001).

Conclusions: Disparities in receipt of CD4 tests elucidate one potential pathway for previously reported disparities in ARV treatment. Further qualitative and quantitative research is needed to identify the specific factors that account for these disparities, so that appropriate interventions can be implemented.