Federal investigators find Medicare Advantage plans deny rehabilitation care at high rates, often reversing denials on appeal

The HHS Inspector General released two reports on Thursday examining prior authorization practices among 19 Medicare Advantage groups in June 2024. The reports found that UnitedHealthcare, CVS Health (Aetna), and Humana — which together cover nearly 20 million Americans — had the highest denial rates for services such as inpatient rehabilitation and long-term acute care, with CVS Health denying 80% of long-term hospital care requests. Denial rates across companies ranged from 8% to 80%, a variation investigators called 'shocking.' When patients appealed, plans overturned denials 95–97% of the time, raising serious questions about whether initial denials were medically warranted. STAT News reported that UnitedHealth Group used a subsidiary called NaviHealth, which employs AI to evaluate care requests, and that insurers themselves found NaviHealth's denials frequently did not hold up on appeal. Experts noted that for-profit insurers denied care at higher rates than nonprofits, and that patients who lose appeals often must pay out of pocket or accept a lower level of care. The OIG recommended that the Centers for Medicare & Medicaid Services collect prior authorization data more regularly and investigate the wide variation in denial rates. Health Secretary Robert F. Kennedy Jr. has pledged reforms, and some insurers have voluntarily reduced the number of services requiring prior authorization, though experts say it is too early to assess the impact.