Humana subsidiary CarePlus Health Plans received $641,467 in net overpayments in 2015, an audit by HHS' Office of Inspector General published Oct. 26 found.
The OIG used the audit sample to estimate CarePlus received $117 million in overpayments during the time period. The government watchdog audited the medical records of 200 CarePlus enrollees for diagnosis codes the agency considers at high risk for upcoding as its sample.
In a statement shared with Becker's, a Humana spokesperson said the company "fundamentally disagrees" with the OIG's report.
"First, the audit holds plans to a documentation standard that is different from the one the government uses to determine how much to pay Medicare Advantage plans. Second, extrapolating these results to the entire contract only magnifies this problem," the spokesperson said. "Third, OIG audited a 2015 plan using a CMS rule that did not exist until 2023, making it impossible to have administered plans consistent with a set of standards that did not yet exist."
The OIG requested CarePlus repay the federal government $641,467, rather than the $117.3 million estimate, because of a CMS rule issued in January that prevents the federal government from collecting extrapolated overpayments before contract year 2018.
Through that rule, CMS said it will strike the fee-for-service adjuster from risk adjustment data validation audits, a tool that would have calculated a permissible level of payment errors and limited audit recoveries to payment errors above that level.
In September, Humana filed a lawsuit in a federal district court challenging the new rule.
"The need for clarity as to how CMS will approach audits of the Medicare Advantage program and assurance that CMS will use an appropriate audit methodology motivated our recent legal action and will remain a priority in our partnership with CMS," the Humana spokesperson said.
Humana has "long advocated" for CMS to audit every MA contract annually, the spokesperson said.
Every major Medicare Advantage insurer has previously been accused of or settled federal allegations of upcoding, or making patients appear sicker than they are on paper to receive higher reimbursements from the government.
The OIG has audited several other payers for overpayments this year, estimating they collectively received at least $82.2 million in overpayments.