Continuous Glucose Monitoring (CGM) offers a dynamic view of blood glucose levels, significantly advancing the daily management of diabetes compared to traditional finger-stick tests. This technology is increasingly used by people with Type 2 Diabetes (T2D) to manage their condition effectively. Navigating Medicare coverage rules can be challenging, as qualification depends on specific medical criteria established by the Centers for Medicare and Medicaid Services (CMS). This article clarifies the requirements and process for T2D patients seeking Medicare coverage for a CGM system.
Understanding Continuous Glucose Monitoring
A Continuous Glucose Monitor is a small, wearable system that tracks glucose levels in the interstitial fluid found between cells. The system consists of three main parts: a sensor inserted just under the skin, a transmitter, and a receiver or smartphone application to display the data. Unlike a single finger-stick test, the CGM provides a new reading every few minutes, day and night.
This continuous stream of data allows the user and their healthcare provider to see glucose trends, including how quickly levels are rising or falling. Seeing these patterns helps inform decisions about diet, exercise, and medication timing. The device also features customizable alerts that notify the user if their glucose is trending too high or too low, which is valuable for preventing dangerous episodes of hypoglycemia.
Medicare Eligibility Requirements for Type 2 Diabetes Coverage
Medicare covers CGM systems and their supplies under Medicare Part B, classifying them as Durable Medical Equipment (DME). To qualify, a patient with Type 2 Diabetes must meet medical necessity criteria. The primary condition for coverage is a diagnosis of diabetes and a prescription for a therapeutic CGM system from a treating healthcare provider.
A T2D patient qualifies for this coverage if they are treated with any type of insulin, regardless of the dose or frequency of administration. This includes patients taking long-acting basal insulin once a day, as well as those on more complex multiple daily injection regimens. This is a significant expansion from previous rules that required patients to be on an intensive insulin regimen.
A patient who does not use insulin can also qualify if they have a documented history of problematic hypoglycemia. This history is defined as experiencing recurring Level 2 hypoglycemic events, where glucose drops below 54 mg/dL, despite attempts to adjust the treatment plan. Qualification also includes having one Level 3 hypoglycemic event, characterized by an altered mental or physical state requiring assistance from another person.
The prescribing practitioner must confirm the patient has the training and ability to use the device as prescribed. This evaluation must occur during a face-to-face or approved telehealth visit within six months prior to ordering the CGM. The device must also be an FDA-approved therapeutic system, cleared for making treatment decisions without requiring a confirmatory finger-stick test.
Navigating the Coverage Process and Costs
Once a patient meets the medical eligibility criteria, the healthcare provider must supply a detailed written order or prescription, often called a Written Order Prior to Delivery (WOPD). This order is sent to a supplier who must be enrolled with Medicare and accept assignment, meaning they agree to accept the Medicare-approved amount as full payment.
Under Medicare Part B, the patient is responsible for the annual Part B deductible and a 20% coinsurance of the Medicare-approved amount for the device and its recurring supplies. Medicare pays the remaining 80% of the cost after the deductible is met. Patients with supplemental insurance, such as Medigap, may have their 20% coinsurance covered by that secondary plan.
For continued coverage, the patient must have a follow-up visit with the prescribing practitioner at least every six months. During these appointments, the provider reviews the CGM data to confirm the device is being used effectively as part of the diabetes management plan. This documentation of ongoing use is required to ensure uninterrupted coverage for replacement sensors and transmitters.
Medicare Advantage and Other Coverage Considerations
For Medicare beneficiaries enrolled in a Medicare Advantage Plan (Part C), the rules for CGM coverage are generally aligned with Original Medicare. Part C plans must cover all medically necessary services and supplies covered by Part A and Part B. Therefore, if a patient meets the Part B medical necessity criteria for a CGM, their Part C plan must cover it.
However, Medicare Advantage plans manage coverage differently through network restrictions and specific cost-sharing structures. Patients may be required to use in-network DME suppliers, and the co-payment or coinsurance structure may differ from the standard 20% Part B coinsurance. Part C beneficiaries should check their specific plan documents for details on approved suppliers and out-of-pocket costs.
Part D Coverage
Medicare Part D covers prescription drugs, typically including injected or inhaled insulin and supplies like syringes. The CGM device, its sensor, and its transmitter are classified as DME and are covered under Part B or Part C. Part D does not cover the CGM hardware.