Tips to streamline workflow and increase likelihood of coverage for CGM

As noted in the recent FPM article “Implementing Continuous Glucose Monitoring in Clinical Practice,” continuous glucose monitoring (CGM) brings a wealth of previously unattainable data to diabetes management and, with it, some new measures of glycemia. But coverage and reimbursement can pose a challenge, as is often the case with newer products and services. Following a few simple tips can give you broader insights into glycemia for you and your patients, increase the likelihood that CGM will be authorized for your patients, and hopefully decrease the time it takes you and your staff to seek and obtain such authorization and to digest this wealth of data. When it comes to billing for CGM services you provide — such as training the patient, setting up the system, and later interpreting the results — a few tips can help streamline your process and ensure reimbursement for your services.

Authorization

The American Academy of Family Physicians (AAFP) does not have specific CGM guidelines related to diabetes management. The American Diabetes Association (ADA) does, however, and updates them regularly. The ADA Standards of Medical Care in Diabetes can help you select patients more likely to benefit from CGM — and to be approved for it. In seeking authorization from an insurance company for CGM for a patient, it can be helpful to quote and reference the ADA Standards that support your recommendation of CGM for that particular patient. The ADA Standards are published in Diabetes Care.

Your medical record can help you here. Where applicable, noting the number of insulin injections per day, the number of glucose checks per day, the presence of hypoglycemia unawareness or reduced awareness, and/or documentation of hypoglycemia can all help with obtaining authorization. It is also helpful to include a brief statement about efforts you have undertaken, prescribed, or recommended to achieve glycemic targets not being met or to decrease the frequency and/or severity of hypoglycemia. An up-to-date medication list and up-to-date laboratory results (and a comment regarding whether the patient is meeting glycemic targets) can also help.

The new world of glycemic measures

For many years, there has been a tremendous focus on A1C as the preferred, and sometimes only, measure of glycemia and diabetes management. However, as it represents an average glucose level over approximately three months, it does not directly provide insight into high glucose levels, low glucose levels, or variability in between, though each of these can be quite important. For example, two patients can have identical A1C values, but one may have little variability, with only modest and infrequent hyperglycemia and hypoglycemia, while a second may have high degrees of variation, frequently shifting between profound hyperglycemia and hypoglycemia, while achieving the same average glucose level as the first patient. This is where the added metrics available from CGM can be especially useful.

• Mean glucose is not new, but is quickly and easily calculated by CGM systems from all of the sensor readings in a given time window.
• Glucose management indicator (GMI, formerly called estimated A1C) is calculated from the average glucose and can be very useful in estimating A1C. The GMI target is the same as the A1C target, which for most people with diabetes is less than 7%.
• Time in range (TIR) is the percentage of time (or the percentage of sensor readings) with glucose between 70 and 180 mg per dL, a range recently standardized by multiple professional groups to allow standardized assessment. The recommended target for most people with diabetes is greater than 70% TIR, as this roughly corresponds to A1C less than 7%. Time in range cannot be assessed without CGM or numerous (several times daily) capillary glucose measurements.
• Time below range (TBR) or time in hypoglycemia is the percentage of time (or sensor readings) with glucose below 70 mg per dL. The recommended target for TBR for most people is less than 5% (with less than 1% “very low” or glucose < 54 mg per dL).
• Glycemic variability (% CV) is the result of the standard deviation of glucose readings divided by the average glucose level (SD/mean) and is calculated by CGM systems. Less variability is associated with better outcomes, and the target for most is ≤ 36%.

Assessing and documenting these few metrics in a systematic way can help you maximize the insights that CGM can provide and streamline your efforts. Simply summarizing them in a note can be very helpful in this regard. Below are some suggested smart text or macros for two popular electronic health record systems that can be used or adapted to other systems.

Reimbursement for CGM related services

Personal and professional CGM startup and training use CPT codes 95249 and 95250, respectively. Be sure that when you bill for these services, your documentation includes a description of sensor placement, hook-up, calibration to a capillary or venous glucose measurement, patient training, sensor removal, and data download/printout, with monitoring for at least 72 hours. When it comes to data interpretation (CPT code 95251), the direction in the code description is more vague (CGM monitoring for at least 72 hours, with “interpretation and report”). Documenting key summary data from the CGM system can not only help your clinical care and shared decision-making with your patient, but can also support your reimbursement for this added service with discrete value.

— Sean M. Oser, MD, MPH, and Tamara K. Oser, MD