Medicare Advantage Denial Challenges for Physician Practices

Medicare Advantage now covers more than 32 million Americans — over half of all Medicare beneficiaries — according to the Kaiser Family Foundation. For physician practices, this shift represents more than a demographic trend. It represents a fundamental change in how claims are processed, how denials are issued, and how appeals must be structured.

Unlike traditional Medicare, which follows a relatively transparent and consistent set of coverage determination rules, Medicare Advantage plans are administered by private insurers who layer their own utilization management protocols on top of Medicare's baseline coverage requirements. The result is a denial landscape that is more complex, less predictable, and — according to multiple federal investigations — frequently more restrictive than traditional Medicare itself.

The OIG Findings: Denials That Should Not Have Happened

A landmark 2022 report from the HHS Office of Inspector General (OIG) examined Medicare Advantage prior authorization denials and payment denials and found that MA plans were denying services that met Medicare coverage rules. The OIG reviewed a sample of denials and concluded that 13% of prior authorization denials and 18% of payment denials involved services that should have been approved under traditional Medicare criteria.

This finding has significant implications for physician practices. It means that a measurable percentage of Medicare Advantage denials are not based on legitimate clinical grounds — they are the product of utilization management criteria that are more restrictive than what Medicare itself requires. For practices that accept the initial denial without appealing, this translates directly to lost revenue for services that were clinically appropriate and covered.

How MA Denials Differ from Commercial Denials

While the appeals process shares some structural similarities with commercial insurance, Medicare Advantage denials differ in several important ways:

• Federal regulatory framework. MA plans are regulated by CMS under federal law, not state insurance departments. This means that state prior authorization reform laws — gold-carding programs, response time mandates, transparency requirements — generally do not apply to MA plans. The regulatory protections available to practices are different.
• Coverage should match traditional Medicare. CMS requires that MA plans cover, at minimum, all services that traditional Medicare covers. When an MA plan denies a service that traditional Medicare would approve, the practice has regulatory grounds for appeal. However, proving this requires understanding both the MA plan's criteria and the applicable Medicare National Coverage Determination (NCD) or Local Coverage Determination (LCD).
• Structured appeal levels. Medicare Advantage appeals follow a defined five-level process: plan reconsideration, Independent Review Entity (IRE) review, Administrative Law Judge (ALJ) hearing, Medicare Appeals Council review, and federal court review. This structure provides more escalation options than most commercial plans, but each level has specific procedural requirements.
• Expedited review requirements. For urgent situations where a standard appeal timeline could jeopardize the patient's health, MA plans are required to provide expedited reconsideration within 72 hours. Many practices are unaware of this right or do not invoke it when clinically appropriate.

The Prior Authorization Expansion in MA

One of the most significant developments in Medicare Advantage is the expansion of prior authorization requirements to services that do not require prior authorization under traditional Medicare. The OIG and CMS have both expressed concern about this trend.

CMS issued a final rule in 2024 (CMS-0057-F) that, among other provisions, requires MA plans to maintain specific prior authorization approval rates and response timeframes. The rule also requires plans to report prior authorization data, including denial and appeal rates, which will create unprecedented transparency into MA plan behavior. However, many of these provisions have staggered implementation dates, and the immediate impact on day-to-day practice operations will take time to materialize.

In the meantime, practices must navigate the reality that each MA plan may apply prior authorization requirements differently, and that the scope of services requiring authorization is often broader than what the practice encounters under traditional Medicare or even under the same insurer's commercial products.

Documentation Strategies for MA Appeals

Given the OIG's finding that a significant percentage of MA denials involve services that meet Medicare coverage criteria, the documentation strategy for MA appeals should be anchored in Medicare's own coverage framework. Specifically:

1. Reference the applicable NCD or LCD. When the denied service is covered under a National Coverage Determination or Local Coverage Determination, the appeal should cite the specific determination by number and demonstrate that the patient meets the stated criteria. This frames the appeal in terms the plan is obligated to respect.
2. Document the clinical basis in Medicare's terms. Medicare coverage criteria use specific clinical language and thresholds. The appeal documentation should mirror this language, making it as easy as possible for the reviewer to map the patient's clinical data to the coverage criteria.
3. Identify criteria that exceed Medicare requirements. If the MA plan's denial is based on criteria that are more restrictive than traditional Medicare, the appeal should explicitly note this discrepancy. CMS has stated that MA plans may not deny coverage for services that traditional Medicare would cover, and highlighting this gap strengthens the regulatory argument.
4. Prepare for IRE escalation. If the plan's internal reconsideration upholds the denial, the case automatically moves to an Independent Review Entity. The documentation package submitted at the first level should be comprehensive enough to support the IRE review without additional work.

The Financial Impact on Practices

The financial stakes of Medicare Advantage denials are substantial and growing. As MA enrollment increases, the proportion of a practice's revenue that flows through MA plans rises correspondingly. For practices serving a primarily Medicare-aged population — geriatrics, rheumatology, orthopedics, cardiology, oncology — MA plans may represent 40% to 60% or more of total revenue.

When denial rates for MA plans exceed those of traditional Medicare — which multiple data sources suggest they do — the revenue impact is amplified by the volume. A practice that writes off MA denials without systematic appeal may be forfeiting 3% to 5% of its total MA revenue, a figure that compounds over time and across patients.

The Regulatory Trajectory

The direction of federal regulation is toward greater MA plan accountability. CMS's 2024 interoperability rule, the OIG's ongoing audits, and Congressional attention to MA denial practices all signal that the regulatory environment will become less permissive of aggressive utilization management. For practices, this means two things: in the near term, understanding your appeal rights and exercising them is critical; in the medium term, the regulatory landscape may shift in ways that reduce the denial burden.

However, relying on regulatory reform to solve the problem is a risky strategy. Reform takes time, and implementation is never instantaneous. The practices that build strong MA denial management processes now will capture revenue that would otherwise be lost during the years it takes for regulatory changes to take full effect.

A Different Challenge Requiring a Different Approach

Medicare Advantage is not simply another commercial payer. It operates under a different regulatory framework, applies different utilization management practices, and requires a different appeal strategy. Practices that treat MA denials the same way they treat commercial denials — using the same templates, the same timelines, and the same documentation — are leaving money on the table and failing to leverage the regulatory protections that the federal framework provides.

The data is clear: MA denials are a significant and growing challenge. The practices that respond with a dedicated, informed strategy will be positioned to recover revenue that others forfeit by default.