Disparities in Biomarkers for Patients With Diabetes After the Affordable Care Act

BACKGROUND: Racial and ethnic minorities are disproportionately affected by diabetes and at greater risk of experiencing poor diabetes-related outcomes compared with non-Hispanic whites. The Affordable Care Act (ACA) was implemented to increase health insurance coverage and reduce health disparities. OBJECTIVE: Assess changes in diabetes-associated biomarkers [hemoglobin A1c (HbA1c) and low-density lipoprotein] 24 months pre-ACA to 24 months post-ACA Medicaid expansion by race/ethnicity and insurance group. RESEARCH DESIGN: Retrospective cohort study of community health center (CHC) patients. SUBJECTS: Patients aged 19-64 with diabetes living in 1 of 10 Medicaid expansion states with ≥1 CHC visit and ≥1 HbA1c measurement in both the pre-ACA and the post-ACA time periods (N=13,342). METHODS: Linear mixed effects and Cox regression modeled outcome measures. RESULTS: Overall, 33.5% of patients were non-Hispanic white, 51.2% Hispanic, and 15.3% non-Hispanic black. Newly insured Hispanics and non-Hispanic whites post-ACA exhibited modest reductions in HbA1c levels, similar benefit was not observed among non-Hispanic black patients. The largest reduction was among newly insured Hispanics versus newly insured non-Hispanic whites (P<0.05). For the subset of patients who had uncontrolled HbA1c (HbA1c≥9%) within 3 months of the ACA Medicaid expansion, non-Hispanic black patients who were newly insured gained the highest rate of controlled HbA1c (hazard ratio=2.27; 95% confidence interval, 1.10-4.66) relative to the continuously insured group. CONCLUSIONS: The impact of the ACA Medicaid expansion on health disparities is multifaceted and may differ across racial/ethnic groups. This study highlights the importance of CHCs for the health of minority populations.