DESCRIPTION
Implantable or noninvasive continuous glucose monitoring systems measure glucose levels in the interstitial fluid at various periods throughout the day. These devices produce data that shows the trends in glucose measurements, in contrast to the isolated glucose measurements of the traditional blood glucose measurements. Physicians can use these systems to retrospectively review blood glucose levels, and adjust therapy to assist in overall glycemic control.
The continuous glucose monitoring systems currently available either measure the blood glucose with minimal invasiveness through continuous measurement of interstitial fluid (ISF), or with the noninvasive method of applying electromagnetic radiation through the skin to blood vessels in the body as describe below.
Minimed® Continuous Glucose Monitoring System (CGMS) reads the glucose level every five minutes through a subcutaneously implanted sensor attached to a small plastic disk taped to the skin, which holds the sensor in place. A thin wire connects the sensor to a pager-sized glucose monitor, which records and stores glucose values in memory.
GlucoWatch® is an external device worn like a wristwatch that measures glucose every 20 minutes in interstitial fluid extracted through the skin with an electric current (referred to as reverse iontophoresis).
While these devices potentially eliminate or decrease the number of required daily capillary blood glucose measurements, it should be noted, according to the FDA labeling, neither is intended to be an alternative to traditional self-monitoring of blood glucose. These devices are intended to serve as an adjunct, supplying additional information on glucose trends that are not available from traditional self-monitoring.
There are also additional devices that now have FDA approval. The FreeStyle Navigator CGM System (Abbott) was approved in March 2008. The sensor for this device can be worn on the back of the upper arm or on the abdomen. As with other CGM devices, information for this device also notes “Before adjusting therapy for diabetes management based on the results and alarms from the FreeStyle Navigator system, traditional blood glucose tests must be performed.” The Paradigm REAL-Time System and Guardian REAL-Time System (Pediatric Versions) (Medtronic, MiniMed) were approved by the FDA in March 2007. These are pediatric versions of previously approved devices. The approval of these devices includes the wording “All therapy adjustments should be based on measurements obtained using a home glucose monitor and not on the sensor glucose readings ….”. This approval was based on the concordance of glucose results between those obtained with the sensor and with a glucose meter. The Paradigm system consists of an insulin infusion pump, the glucose sensor, and a transmitter.
POLICY
Short-term (intermittent) use of continuous interstitial glucose monitoring as an adjunct to standard care, is considered medically necessary in the management of Type I diabetics (including subtypes Type 1A/autoimmune and Type 1B/idiopathic diabetes) if the medical appropriateness criteria are met. (See Medical Appropriateness below.)
Long-term use of interstitial glucose monitoring, as an adjunct to standard care, is considered medically necessary in the management of Type I diabetics (including subtypes Type 1A/autoimmune and Type 1B/idiopathic diabetes) if the medical appropriateness criteria are met. (See Medical Appropriateness below.)
Any device utilized for this procedure must have FDA approval specific to the indication, otherwise it will be considered investigational.
MEDICAL APPROPRIATENESS
Interstitial glucose monitoring is considered medically appropriate in the management of Type 1 diabetics as an adjunct to standard care if ANY ONE of the following are met:
Short-term use of interstitial glucose monitoring with ALL the following:
Inadequate glycemic control despite compliance with frequent self monitoring (at least four times per day) and including fasting hyperglycemia (greater than 150 mg/dl) or recurring episodes of severe hypoglycemia (less than 50 mg/dl). This poor control is in spite of compliance with multiple alterations in self-monitoring and insulin administration regimens to optimize care
Insulin injections are required three (3) or more times per day or an insulin pump is used for maintenance of blood sugar control
Four (4) or more capillary blood glucose measurements are required per day
Monitoring and interpretation under the supervision of a physician
The device is only used for seventy-two (72) consecutive hours on an appropriate, periodic basis
Note: Short-term continuous interstitial glucose monitoring is used episodically to direct changes in diabetic management. Given the several month timeframe necessary to determine the efficacy of these treatment modifications, it is anticipated that when the above medical appropriateness criteria are met, continuous glucose monitoring devices would be used up to two times in a given year.
Long-term use of interstitial glucose monitoring with ALL of the following:
ANY ONE of the following are met:
Recurrent episodes of severe hypoglycemia with blood glucose less than 50 mg/dl
During the course of pregnancy
When ALL of these criteria are met:
Inadequate glycemic control despite compliance with frequent self-monitoring (at least four times per day) and including fasting hyperglycemia (greater than 150 mg/dl) or recurring episodes of severe hypoglycemia (less than 50 mg/dl). This poor control is in spite of compliance with multiple alterations in self-monitoring and insulin administration regimens to optimize care
Insulin injections are required three (3) or more times per day or an insulin pump is used for maintenance of blood sugar control
Four (4) or more capillary blood glucose measurements are required per day
IMPORTANT REMINDER
We develop Medical Policies to provide guidance to Members and Providers. This Medical Policy relates only to the services or supplies described in it. The existence of a Medical Policy is not an authorization, certification, explanation of benefits or a contract for the service (or supply) that is referenced in the Medical Policy. For a determination of the benefits that a Member is entitled to receive under his or her health plan, the Member's health plan must be reviewed. If there is a conflict between the Medical Policy and a health plan, the express terms of the health plan will govern.
ADDITIONAL INFORMATION
Continuous glucose monitoring devices are intended for prescription use only.
The Minimed® Continuous Glucose Monitoring System readings will be available for review by physicians only after the entire recording interval (suggested as 72-hours).
These devices are only used as a supplement to, and not a replacement for, standard invasive measurement.
SOURCES
American Diabetes Association. (2011). Standards of medical care in diabetes - 2011. Retrieved December 27, 2011 from http://care.diabetesjournals.org/content/34/Supplement_1/S11.full.pdf+html. (395 articles and/or guidelines reviewed)
BlueCross BlueShield Association. Medical Policy Reference Manual. (3:2012). Continuous or intermittent monitoring of glucose in the interstitial fluid (1.01.20). Retrieved April 17, 2012 from BlueWeb. (19 articles and/or guidelines reviewed)
BlueCross BlueShield of Tennessee network endocrinologists. July 2008.
Hayes. Medical Technology Directory. (2010, December). Continuous glucose monitoring systems. Retrieved February 23, 2011 from www.Hayesinc.com/subscribers. (95 articles and/or guidelines reviewed)
Klonoff, David C., Buckinham, Bruce, Christiansen, Jens S., Montori, Victor M., Tamborlane, William V., Vigersky, Robert A., et al. (2011). Continuous glucose monitoring: An Endocrine Society clinical practice guideline. Journal of Clinical Endocrinology & Metabolism, 96 (10), 2968-2979.
U. S. Food and Drug Administration. (2001, March). Center for Devices and Radiological Health. Premarket approval decision for March 2001. Retrieved May 12, 2008 from http://www.fda.gov/cdrh/pdf/P990026a.pdf.
U. S. Food and Drug Administration. (2006, March). Center for Devices and Radiological Health. Premarket approval decision for March 2006. Retrieved May 12, 2008 from http://www.fda.gov/cdrh/pdf5/p050012a.pdf.
U. S. Food and Drug Administration. (2007, March). Center for Devices and Radiological Health. Premarket approval decision for March 2007. Retrieved May 12, 2008 from http://www.fda.gov/cdrh/pdf/p980022s015a.pdf.
U. S. Food and Drug Administration. (2008, March). Center for Devices and Radiological Health. Premarket approval decision for March 2008. Retrieved May 12, 2008 from http://www.fda.gov/cdrh/pdf5/p050020a.pdf.
Vigersky, R., Fonda, S. J., Chellappa, M., Walker, M. S., & Ehrhardt, N. M. (2012). Short- and long-term effects of real-time continuous glucose monitoring in patients with type 2 diabetes. Diabetes Care, 35 (1), 32-38.
ORIGINAL EFFECTIVE DATE: 2/1/2001
MOST RECENT REVIEW DATE: 4/17/2012
ID_BT
Policies included in the Medical Policy Manual are not intended to certify coverage availability. They are medical determinations about a particular technology, service, drug, etc. While a policy or technology may be medically necessary, it could be excluded in a member's benefit plan. Please check with the appropriate claims department to determine if the service in question is a covered service under a particular benefit plan. Use of the Medical Policy Manual is not intended to replace independent medical judgment for treatment of individuals. The content on this Web site is not intended to be a substitute for professional medical advice in any way. Always seek the advice of your physician or other qualified health care provider if you have questions regarding a medical condition or treatment.