OIG audit of Humana Medicare Advantage contract underscores continued scrutiny of high-risk diagnoses and ongoing disputes over audit methodology

On December 16, HHS-OIG published the results of its audit of a Louisiana-based Medicare Advantage contract for Humana, the second-largest Medicare Advantage organization in the country.1 OIG's audit continues a pattern of heightened regulatory scrutiny of certain 'high-risk' diagnosis codes submitted by MAOs for payment from CMS.  The audit is HHS's latest move in a long-running set of disputes over alleged overpayments to MAOs. As we described in a recent client alert, these issues remain the subject of litigation that will affect CMS's authority to extrapolate adverse audit findings. The outcome of these disputes—and the evolving standards for audits conducted by both OIG and CMS—will have significant implications for MAO compliance, audit exposure, and payment integrity going forward.