Democrats on a Senate subcommittee have accused UnitedHealthcare Group of increasingly denying patient claims, leveraging artificial intelligence (AI) for automation. An October report by the U. S. Senate Permanent Subcommittee on Investigations found that UnitedHealthcare's denial rate for post-acute care claims rose from 10. 9% in 2020 to 22. 7% in 2022, with denial rates for skilled nursing centers notably surging ninefold since 2019. During this time, UnitedHealthcare adopted automation initiatives like "Machine Assisted Prior Authorization, " which reportedly sped up claim reviews but also increased denials due to error detection. UnitedHealthcare was criticized as it processed more home health service authorizations but allegedly favored cost-effective alternatives over post-acute care.

The company refuted the report's claims, saying it mischaracterizes their clinical practices and the Medicare Advantage program. A class-action lawsuit in November 2023 accused UnitedHealthcare and subsidiary NaviHealth of using a flawed AI algorithm with a 90% error rate to deny Medicare claims in nursing homes, bypassing physicians' determinations. Allegedly, only 0. 2% of policyholders appeal denials, and many patients end up paying out-of-pocket or not receiving needed care. An investigation revealed UnitedHealth pressured employees to use AI algorithms to determine patient stays, impacting Medicare payments. This scrutiny intensified following the murder of UnitedHealthcare CEO Brian Thompson, prompting criticism of the company.