Continuous Glucose Monitoring

POLICY NUMBER

A.1.01.20

DESCRIPTION

Tight glucose control in patients with diabetes has been associated with improved health outcomes. Several devices are available to measure glucose levels automatically and frequently (e.g., every 5 to 10 minutes). The devices measure glucose in the interstitial fluid and are approved as adjuncts to or replacements for traditional self-monitoring of blood glucose levels. Devices can be used on a long-term (continuous) or short-term (often referred to as intermittent) basis.

Blood Glucose Control

The advent of blood glucose monitors for use by patients in the home revolutionized the management of diabetes. Using fingersticks, patients can monitor their blood glucose levels both to determine the adequacy of hyperglycemia control and to evaluate hypoglycemic episodes. Tight glucose control, defined as a strategy involving frequent glucose checks and a target hemoglobin A_1C (HbA_1C) level in the range of 7%, is now considered standard of care for patients with diabetes. Randomized controlled trials assessing tight control have demonstrated benefits for patients with type 1 diabetes in decreasing microvascular complications. The impact of tight control on type 1 diabetes and macrovascular complications such as stroke or myocardial infarction is less certain. The Diabetes Control and Complications Trial (2002) demonstrated that a relative HbA_1C level reduction of 10% is clinically meaningful and corresponds to approximately a 40% decrease in risk for progression of diabetic retinopathy and 25% decrease in risk for progression of renal disease.

Due to an increase in turnover of red blood cells during pregnancy, HbA_1C levels are slightly lower in women with a normal pregnancy compared with nonpregnant women. The target HbA_1C in women with diabetes is also lower in pregnancy. The American Diabetes Association recommends that, if achievable without significant hypoglycemia, the HbA_1C levels should range between 6.0 to 6.5%; an HbA_1C level less than 6% may be optimal as the pregnancy progresses.

Tight glucose control requires multiple daily measurements of blood glucose (i.e., before meals and at bedtime), a commitment that some patients may find difficult to meet. The goal of tight glucose control has to be balanced with an associated risk of hypoglycemia. Hypoglycemia is known to be a risk in patients with type 1 diabetes. While patients with insulin-treated type 2 diabetes may also experience severe hypoglycemic episodes, there is a lower relative likelihood of severe hypoglycemia compared with patients who had type 1 diabetes. An additional limitation of periodic self-measurements of blood glucose is that glucose values are seen in isolation, and trends in glucose levels are undetected. For example, while a diabetic patient's fasting blood glucose level might be within normal values, hyperglycemia might be undetected postprandially, leading to elevated HbA_1C levels.

Management

Measurements of glucose in the interstitial fluid have been developed as a technique to measure glucose values automatically throughout the day, producing data that show the trends in glucose levels. Although devices measure glucose in the interstitial fluid on a periodic rather than a continuous basis, this type of monitoring is referred to as continuous glucose monitoring (CGM).

Currently, CGM devices are of 2 designs; real-time CGM (rtCGM) provides real-time data on glucose level, glucose trends, direction, and rate of change, and intermittently viewed (iCGM) devices that show continuous glucose measurements retrospectively. These devices are also known as flash-glucose monitors.

Approved devices now include devices indicated for pediatric use and those with more advanced software, more frequent measurements of glucose levels, or more sophisticated alarm systems. Devices initially measured interstitial glucose every 5 to 10 minutes and stored data for download and retrospective evaluation by a clinician. With currently available devices, the intervals at which interstitial glucose is measured range from every 1 to 2 minutes to 5 minutes, and most provide measurements in real-time directly to patients. While continuous glucose monitoring potentially eliminates or decreases the number of required daily fingersticks, according to the U.S. Food and Drug Administration (FDA) labeling, some marketed monitors are not intended as an alternative to traditional self-monitoring of blood glucose levels but rather as adjuncts to monitoring, supplying additional information on glucose trends not available from self-monitoring while other devices are factory calibrated and do not require fingerstick blood glucose calibration.

Devices may be used intermittently (ie, for periods of 72 hours) or continuously (ie, on a long-term basis).

Multiple CGM systems have been approved or cleared by the FDA (see the table below). FDA product codes: [PMA] QCD, MDS, PQF; [510(k)] QBJ, QLG, SAF.

CGM devices labeled as “Pro” for specific professional use with customized software and transmission to health care professionals are not enumerated in this list.

The Flash glucose monitors (eg FreeStyle Libre, Abbott) use intermittent scanning. The current version of the FreeStyle Libre device includes real-time alerts, in contrast to earlier versions without this feature.

CGM Systems Approved or Cleared by the U.S. Food and Drug Administration

 Related medical policies - 

• Artificial Pancreas Device Systems

POLICY

Individuals with Type 1 Diabetes

Long-term continuous glucose monitoring (CGM) device monitoring of glucose levels in interstitial fluid, as a technique of diabetic monitoring, may be considered medically necessary in individuals with type 1 diabetes who have demonstrated an understanding of the technology, are motivated to use the device correctly and consistently, are expected to adhere to a comprehensive diabetes treatment plan supervised by a qualified provider, and are capable of using the device to recognize alerts and alarms.

Short-term CGM monitoring of glucose levels in interstitial fluid may be considered medically necessary in individuals with type 1 diabetes whose diabetes is poorly controlled, despite current use of best practices (see Policy Guidelines). Poorly controlled type 1 diabetes includes the following clinical situations: unexplained hypoglycemic episodes, hypoglycemic unawareness, suspected postprandial hyperglycemia, and recurrent diabetic ketoacidosis.

Short-term CGM monitoring of glucose levels in interstitial fluid may also be considered medically necessary in individuals with type 1 diabetes prior to insulin pump initiation to determine basal insulin levels.

Individuals with Type 2 Diabetes

Long-term CGM monitoring of glucose levels in interstitial fluid may be considered medically necessary in individuals with type 2 diabetes who are treated with insulin therapy and are willing and able to use the device and have adequate medical supervision.

Short-term CGM monitoring of glucose levels in interstitial fluid may be considered medically necessary in individuals with type 2 diabetes who require multiple daily doses of insulin and whose diabetes is poorly controlled, despite current use of best practices (see Policy Guidelines section) and are capable of using devices safely. Poorly controlled type 2 diabetes includes the following clinical situations: unexplained hypoglycemic episodes, hypoglycemic unawareness, persistent hyperglycemia, or hemoglobin A1c (HbA1c) levels above target.

Short-term CGM monitoring of glucose levels in interstitial fluid may be considered medically necessary in individuals with type 2 diabetes who require multiple daily doses of insulin to determine basal insulin levels prior to insulin pump initiation.

Short-term and long-term CGM monitoring of glucose levels in interstitial fluid in individuals with type 2 diabetes is considered investigational for individuals who do not meet the above criteria.

Other uses of long-term and short-term CGM monitoring of glucose levels in interstitial fluid as a technique of diabetic monitoring including use in gestational diabetes not requiring insulin therapy are considered investigational.

The use of implantable CGM devices for management of type 1 and type 2 diabetes mellitus is considered investigational.

POLICY EXCEPTIONS

Federal Employee Program (FEP) may dictate that all FDA-approved devices, drugs or biologics may not be considered investigational and thus these devices may be assessed only on the basis of their medical necessity.

Ivey Mechanical: Effective 09/01/2020, continuous glucose monitoring devices are covered for type 1 and type 2 diabetic patients, regardless of medical necessity.

POLICY GUIDELINES

The coverage guidelines outlined in the Medical Policy Manual should not be used in lieu of the Member's specific benefit plan language.

This policy only evaluates continuous (real time or intermittently scanned) interstitial glucose monitors and does not evaluate insulin pumps. Insulin pump systems with a built-in continuous glucose monitor and a low-glucose suspend feature are addressed in the  Artificial Pancreas Device Systems policy.

Short-term continuous glucose monitoring is generally conducted over 72-hour periods. It may be repeated subsequently depending on the individual's level of diabetes control.

Best practices in diabetes control include compliance with a self-monitoring blood glucose regimen of 4 or more fingersticks each day and use of an insulin pump or multiple daily injections of insulin. During pregnancy, 3 or more insulin injections daily could also be considered best practice for individuals not on an insulin pump prior to the pregnancy. Prior short-term (72-hour) use of an intermittent glucose monitor would be considered a part of best practices for those considering long-term use of a continuous glucose monitor.

Significant hypoglycemia may include recurrent, unexplained, severe (generally blood glucose levels <50 mg/dL) hypoglycemia or impaired awareness of hypoglycemia that puts the individual or others at risk.

Individuals with type 1 diabetes taking insulin who are pregnant or about to become pregnant with poorly controlled diabetes are another subset of individuals to whom the policy statement on short-term continuous glucose monitoring may apply.

The strongest evidence exists for use of continuous glucose monitoring devices in individuals age 25 years and older. However, age may be a proxy for motivation and good control of disease, so it is also reasonable to select patients based on their ability to self-manage their disease, rather than their age. Multiple continuous glucose monitoring (CGM) devices have U.S. Food and Drug Administration labeling related to age.

Providers board-certified in endocrinology and/or providers with a focus on the practice of diabetes care may be considered qualified to evaluate and oversee individuals for continuous (ie, long-term) monitoring.

Medically Necessary is defined as those services, treatments, procedures, equipment, drugs, devices, items or supplies furnished by a covered Provider that are required to identify or treat a Member's illness, injury or Mental Health Disorders, and which Company determines are covered under this Benefit Plan based on the criteria as follows in A through D:

A.  consistent with the symptoms or diagnosis and treatment of the Member's condition, illness, or injury; and

B.  appropriate with regard to standards of good medical practice; and

C.  not solely for the convenience of the Member, his or her Provider; and

D.  the most appropriate supply or level of care which can safely be provided to Member. When applied to the care of an Inpatient, it further means that services for the Member's medical symptoms or conditions require that the services cannot be safely provided to the Member as an Outpatient.

For the definition of medical necessity, “standards of good medical practice” means standards that are based on credible scientific evidence published in peer-reviewed medical literature generally recognized by the relevant medical community, and physician specialty society recommendations, and the views of medical practitioners practicing in relevant clinical areas and any other relevant factors. BCBSMS makes no payment for services, treatments, procedures, equipment, drugs, devices, items or supplies which are not documented to be Medically Necessary. The fact that a Physician or other Provider has prescribed, ordered, recommended, or approved a service or supply does not in itself, make it Medically Necessary.

Investigative is defined as the use of any treatment procedure, facility, equipment, drug, device, or supply not yet recognized as a generally accepted standard of good medical practice for the treatment of the condition being treated and; therefore, is not considered medically necessary. For the definition of Investigative, “generally accepted standards of medical practice” means standards that are based on credible scientific evidence published in peer-reviewed medical literature generally recognized by the relevant medical community, and physician specialty society recommendations, and the views of medical practitioners practicing in relevant clinical areas and any other relevant factors. In order for equipment, devices, drugs or supplies [i.e, technologies], to be considered not investigative, the technology must have final approval from the appropriate governmental bodies, and scientific evidence must permit conclusions concerning the effect of the technology on health outcomes, and the technology must improve the net health outcome, and the technology must be as beneficial as any established alternative and the improvement must be attainable outside the testing/investigational setting.

POLICY HISTORY

2/2001: Approved by Medical Policy Advisory Committee (MPAC).

4/2/2001: CPT code 84945 and ICD-9 procedure code 99.99 deleted. ICD-9 diagnosis code 250.23 and 250.33 added.

2/15/2002: Investigational definition added.

2/25/2002: Code Reference, Sources and Place of Service sections updated

3/13/2002: E0609 deleted, 92950 (typo) should have been 95250, 99091 moved to non-covered

4/18/2002: Type of Service and Place of Service deleted

4/17/2003: FDA approved labeling for the GlucoWatch "first bullet" expanded to include children/adolescents (age 7 to 17)

6/12/2003: Clarification of changes 4/17/2003. GlucoWatch® G2™ Biographer (G2™ Biographer) information added to Description section.

9/5/2003: Policy reviewed, no changes

10/16/2003: GlucoWatch clarification statement added to "Policy" section

1/27/2004: Sources updated

2/10/2004: Sources updated

11/3/2004: Code Reference section reviewed, no changes

3/13/2006: Coding updated. CPT4 2006 revisions added to policy

3/20/2006: Policy reviewed, no changes

3/27/2007: Policy reviewed and updated. Covered codes table deleted. CPT codes 95250, 95251, and HCPCS S1031 moved to non-covered. Removed the following policy statement, "Continuous monitoring of glucose in the interstitial fluid is considered investigational except for patients with type 1 diabetes who have not achieved adequate glycemic control in spite of frequent self-monitoring of fingerstick blood glucose levels. BCBSMS will only approve the MiniMed monitoring system. Usage of which will be for a finite period of time (Rental)."

7/19/2007: Reviewed and approved by MPAC

12/17/2007: Coding updated. CPT/HCPCS 2008 revisions added to policy.

4/25/2008: Policy reviewed, description section updated

12/31/2008: Code reference section updated per the 2009 CPT/HCPCS revisions

1/8/2009: Policy reviewed and updated. Policy statement updated to allow intermittent monitoring in patients with type I diabetes whose diabetes is poorly controlled, prior to insulin pump initiation to determine basal insulin levels and according to best practice guidelines. Policy guidelines updated to include Best Practice guidelines. Codes updated to reflect covered codes.

04/26/2010: Added “or Intermittent” to the policy title. Policy description and statement unchanged. FEP verbiage added to the Policy Exceptions section. Deleted outdated references from the Sources section.

04/20/2011: Policy reviewed; no changes.

04/26/2012: Policy reviewed; policy statement unchanged. Policy guidelines updated to state the following:  Several insulin pump systems (e.g., Omnipod Insulin Management System, Paradigm REAL-Time System) have a built-in continuous glucose monitor (CGM). This policy is evaluating the CGM-device only; the policy does not evaluate insulin pumps. Insulin pumps are addressed in the External Infusion Pumps policy.

09/03/2013: Added the following investigational policy statement: Use of an artificial pancreas system, including but not limited to closed-loop monitoring devices with low-glucose suspend (LGS) features, are considered investigational. Deleted "symptomatic" from the first bullet in the third policy statement. Intent of policy statement unchanged.

04/23/2014: Policy reviewed; description updated regarding available devices. Added "mellitus" to the first policy statement. Intent of policy statement unchanged.

08/26/2015: Policy description updated to remove information regarding artificial pancreas device systems. Removed the following policy statement: Use of an artificial pancreas system, including but not limited to closed-loop monitoring devices with low-glucosesuspend (LGS) features, are considered investigational. Policy guidelines updated. Medical policy revised to add ICD-10 codes.

04/26/2016: Policy Guidelines updated to add medically necessary and investigative definitions.

05/31/2016: Policy number A.1.01.20 added.

07/12/2016: Policy description updated regarding hypoglycemia and devices. OmniPod Insulin Management System removed from the policy as it does not have a continuous glucose monitor included. "Diabetes mellitus" changed to "diabetes" throughout policy. First policy statement updated to change "up to 72 hours" to "72 hours." Re-worded second bullet point on policy statement regarding continuous monitoring of glucose levels; intent unchanged. Added link to Artificial Pancreas Device Systems policy in Policy Guidelines.

12/30/2016: Code Reference section updated to revise ICD-10 diagnosis code range: E10.10 - E13.9 should be E10.10 - E10.9. Added new 2017 CPT codes 0446T, 0447T, and 0448T.

01/13/2017: Removed CPT codes 0446T, 0447T, and 0448T, pending FDA approval.

06/27/2017: Code Reference section updated to add new HCPCS codes K0553 and K0554, effective 07/01/2017.

08/18/2017: Policy description updated regarding devices. Medically necessary statement regarding continuous (ie, long-term) monitoring of glucose updated to add the following criteria: 1) patients with type 1 diabetes who have demonstrated an understanding of the technology, are motivated to use the device correctly and consistently, are expected to adhere to a comprehensive diabetes treatment plan supervised by a qualified provider, and are capable of using the device to recognize alerts and alarms 2) patients with impaired awareness of hypoglycemia. Policy Guidelines updated regarding providers who may be qualified to evaluate and oversee individuals for continuous (ie, long-term) monitoring.

12/22/2017: Code Reference section updated to add new 2018 CPT code 95249. Revised descriptions for CPT codes 95250 and 95251 effective 01/01/2018.

03/28/2018: Policy description updated regarding blood glucose control. Investigational statement updated to include other uses of intermittent monitoring.

07/19/2018: Policy description updated regarding FDA approved devices. Policy statement unchanged.

12/27/2018: Code Reference section updated to revise code description for CPT code 99091, effective 01/01/2019.

02/14/2019: Policy description updated regarding devices. Policy statements unchanged.

12/20/2019: Code Reference section updated to add new HCPCS code A4226 effective 01/01/2020.

10/07/2020: Policy Exceptions updated to add the following for Ivey Mechanical: Effective 09/01/2020, continuous glucose monitoring devices are covered for type 1 and type 2 diabetic patients, regardless of medical necessity.

03/28/2022: Code Reference section updated to add new 04/01/2022 HCPCS codes A4238 and E2102.

06/28/2022: Code Reference section updated to add HCPCS codes G0308 and G0309, effective 07/01/2022.

12/20/2022: Code Reference section updated to add new HCPCS codes A4239 and E2103. Revised the code description for HCPCS codes A4238, A9276, A9277, A9278, and E2102, effective 01/01/2023.

01/15/2024: Policy title changed from "Continuous or Intermittent Monitoring of Glucose in Interstitial Fluid" to "Continuous Glucose Monitoring." Policy description updated regarding devices. Policy section updated to add coverage criteria for individuals with type 2 diabetes. Policy Guidelines updated regarding significant hypoglycemia and devices. Code Reference section updated to remove deleted HCPCS codes G0308, G0309, K0553, and K0554. Added ICD-10 diagnosis codes E11.00 - E11.9 that must be reported with additional code Z79.4.

08/05/2024: Policy description updated regarding devices. Policy statements unchanged. Policy Guidelines updated regarding best practices in diabetes control.

10/01/2024: Code Reference section updated to add new ICD-10 diagnosis codes E10.A0, E10.A1, and E10.A2.

12/20/2024: Code Reference section updated to add new HCPCS codes G0564 and G0565 effective 01/01/2025.

02/28/2025: Policy statement revised to state: Other uses of long-term and short-term CGM monitoring of glucose levels in interstitial fluid as a technique of diabetic monitoring including use in gestational diabetes not requiring insulin therapy are considered investigational. Code Reference section updated to add ICD-10 diagnosis codes O24.011, O24.012, O24.013, O24.019, O24.03, O24.414, and O24.434.

SOURCE(S)

Blue Cross Blue Shield Association Policy # 1.01.20

CODE REFERENCE

This may not be a comprehensive list of procedure codes applicable to this policy.

The code(s) listed below are ONLY medically necessary if the procedure is performed according to the "Policy" section of this document.   

Covered Codes

Investigational Codes

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