Association between private insurance and living donor kidney transplant: Affordable Care Act as a natural experiment.

Background: Private insurance coverage is associated with higher rates of living donor kidney transplantation (LDKT) but whether this is attributable to confounding is not known.

Aim: To study the association between increased access to private health insurance and LDKT.

Methods: Retrospective cohort study using United States transplant registry data. We identified incident candidates aged 22-29 years who were waitlisted for a kidney-only transplant from 2005-2014, excluding prior transplant recipients and those with missing data. We calculated the hazard of LDKT after waitlisting for those with private insurance vs other insurance pre-Affordable Care Act (ACA) vs post-ACA, using death and delisting as competing events, for candidates affected by the policy change (age 22-25 years) vs those who were not (age 26-29 years).

Results: A total of 13817 candidates were included, of whom 46% were age 22-25 years and 54% were age 26-29 years. Among candidates aged 22-25 years at listing, those listed post-ACA were more likely to have private insurance compared to those listed pre-ACA (42% vs 35%), but there was no difference in private insurance coverage between eras among candidates aged 26-29 years at listing. In adjusted competing risk regression, privately insured patients age 22-25 years were less likely to receive a LDKT post-ACA compared to pre-ACA [hazard ratio (HR) = 0.88, 95%CI: 0.78-1.00], as were those aged 22-25 years old with other insurance types (HR = 0.80, 95%CI: 0.69-0.92). These associations were not seen among candidates age 26-29 years.

Conclusion: Candidates age 22-25 years were likelier to have private insurance post-ACA, without an increased rate in LDKT. Demonstrations of associations between insurance and LDKT are likely attributable to residual confounding.