Status of the Senate Investigation into United Healthcare
The United States Senate has significantly intensified its scrutiny of United Health Group (UHG) in early 2026, building on scrutiny that began with investigative reporting in 2024 and expanded into Department of Justice investigations in 2025.1,2 Current oversight centers on multiple investigations of the company’s business practices, particularly its Medicare Advantage billing strategies, alongside separate inquiries into its care delivery practices, including nursing home policies.
The Centers for Medicare & Medicaid Services (CMS) uses risk-adjustment scores to account for differences in patient health status across Medicare Advantage plans. Each enrollee is assigned a risk score based on documented diagnoses and demographic factors, with higher scores reflecting a greater burden of illness. Because CMS reimburses insurers on a per-beneficiary basis adjusted for these scores, patients with more documented conditions generate higher payments.
On January 12, 2026, Senator Chuck Grassley released a Senate Judiciary Committee majority staff report based on a review of more than 50,000 pages of UHG internal documents. The report found that UHG employed “aggressive strategies” to increase Medicare Advantage risk-adjustment scores, suggesting that the company has effectively transformed risk adjustment into a significant profit-generating mechanism.
According to the report, UHG leveraged its size, data infrastructure, and workforce. including in-home clinicians and coding specialists, to capture a greater volume of diagnoses than its competitors, resulting in higher payments from the Centers for Medicare & Medicaid Services (CMS).1 For example, the report described how UHG supported diagnosis capture through provider training, data analytics, and structured workflows designed to identify additional billable conditions. While the report did not conclude that these practices were unlawful, it emphasized that the practices may undermine the intended purpose of the Medicare Advantage risk-adjustment system.1
In parallel, United Healthcare faces a separate investigation led by members of the Senate Finance Committee, Senators Ron Wyden and Elizabeth Warren, focusing on its nursing home practices through its Optum division, which includes in-home clinicians (Optum Health) and coding infrastructure (Optum Insight). This investigation centers on a program that provides financial incentives to nursing homes to reduce hospital transfers. While this program is beneficial to UHC financially in reducing spending, it has raised concerns that such policies could delay or limit access to necessary acute care for patients.3
As of January 2026, this inquiry has been marked by disputes over document production, with Wyden and Warren alleging that UHG has failed to provide sufficient internal records related to its hospitalization policies and incentive structures.
In a January 8 letter, the senators stated that the company had offered only limited responses during a prior briefing and cited whistleblower materials suggesting that nursing homes were encouraged to consult UHG-affiliated services before transferring patients to hospitals. The senators set a deadline for compliance and indicated that further action could follow if document requests were not fulfilled. UHG stated it will “continue to engage” with the lawmakers while defending the safety and ethics of its nursing home program.3
Taken together, these developments reflect an escalation of federal scrutiny. In addition to congressional oversight, UnitedHealth Group is facing separate federal investigations, including ongoing Department of Justice inquiries into potential fraud related to its Medicare Advantage billing and risk-adjustment practices.4
References
- US Senate Committee on the Judiciary. How UnitedHealth Group puts the risk in Medicare Advantage risk adjustment: majority staff report. Published January 2026. Available from: https://www.grassley.senate.gov/imo/media/doc/uhg_report_-_final.pdf
- Weaver C, Mathews AW, McGinty T. UnitedHealth’s Army of Doctors Helped It Collect Billions More From Medicare. The Wall Street Journal. December 29, 2024. Available from: https://www.wsj.com/health/healthcare/unitedhealth-medicare-payments-doctors-c2a343db
- Joseph G. Senators claim UnitedHealth is withholding internal documents from inquiry. The Guardian. Published January 8, 2026. Accessed March 25, 2026. Available from: https://www.theguardian.com/us-news/2026/jan/08/senate-inquiry-unitedhealth-nursing-homes
- Roy S. DOJ investigates Medicare billing practices at UnitedHealth, WSJ reports. Reuters. 2025 Feb 21. Available from: https://www.reuters.com/business/healthcare-pharmaceuticals/doj-investigates-medicare-billing-practices-unitedhealth-wsj-reports-2025-02-21/