CVS: OIG conducting audit of Aetna's Medicare Advantage plans

The Department of Health and Human Services' Office of Inspector General (HHS-OIG) is putting Aetna's Medicare Advantage plans under the microscope, the insurer's parent company, CVS Health, disclosed Wednesday.

CVS said in the Securities and Exchange Commission filing that the OIG is taking a closer look at the insurer's "risk-adjustment related data." Other insurers, including Anthem and Humana, have come under similar scrutiny.

There has been a significant push to take a closer look at how insurers are submitting such data as the program grows in popularity—and profitability.

"The Company expects [the Centers for Medicare & Medicaid Services] and the OIG to continue these types of audits," CVS said in the filing.

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Earlier this year, the feds said a Florida Humana plan overcharged Medicare by more than $200 million, the largest audit penalty ever posed on an MA plan. Shortly thereafter, OIG said Medicare overpaid Anthem in MA by nearly $3.5 million.

MA payments are calculated based on regional factors and spending in fee-for-service Medicare, so the government pays MA plans for members with higher acuity needs, like chronic conditions.

Critics allege that insurers will add unneeded codes or otherwise inflate their risk scores in order to boost payouts. MA plans, meanwhile, argue that the OIG uses flawed methodology to measure overpayment, as it bases its analyses on a small sample.

In the case of Anthem, for example, OIG extrapolated overall payouts from a sample of about $354,000 in inappropriate payments.

CVS flagged the audit as part of its quarterly earnings report released Wednesday morning.