Perspective:

This is an important study that attempts to address a great unknown: What will the impact of the national ACA have on health care disparities in vulnerable populations? Overall, I interpret this study as pointing out the complexities around understanding and addressing health care disparities. The authors point out several reasons for their null findings, including the role of other social determinants of health care (beyond insurance), the potential for underinsurance, and the lack of change in referral patterns for these patients who continue to be cared for by organizations with fewer resources. There are important limitations to consider such as data from a single state with a unique health care environment (e.g., ‘free care pool’ in Massachusetts prior to reform) and a lack of clinically granular data (i.e., ensuring that disparities reflected underuse in vulnerable populations rather than overuse in others). Despite these limitations, this paper reminds us that to truly tackle disparities will require a more comprehensive effort, and that expanded access to insurance is only a piece of the puzzle.