Blood Glucose Monitors are eligible for coverage in order to achieve diabetic control by self-monitoring for diabetics who are:

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1 COVERAGE: Blood Glucose Monitors are eligible for coverage in order to achieve diabetic control by self-monitoring for diabetics who are: Insulin treated/dependent (type I or II) (IDDM), Non-insulin treated/dependent (type II) (NIDDM), or Diagnosed as gestational diabetic patients. Monitoring of glucose levels in the interstitial fluid as a technique of diabetic monitoring is considered experimental or investigational. Despite this position, interstitial monitoring may be eligible for coverage due to state specific legislative mandates. (See section below for more information on the Texas state mandate.) LEGISLATIVE MANDATES: For Texas: Legislative mandates for insured (individual or group) business require coverage for diabetic equipment and supplies that are approved by the United States Food and Drug Administration, if such equipment or supplies are determined to be medically necessary and appropriate by a treating physician. DESCRIPTION: A Blood Glucose Monitor (Glucometer, Accu-Chek and Tracer II) is a portable battery-operated meter used to determine the blood glucose level by exposing a reagent strip to a small sample of blood. The patient uses a disposable lancet, draws a drop of blood, places it on a reagent strip, and inserts it into the monitor. The monitor determines glucose concentration in the patient's blood by measuring the intensity of color change on the treated reagent strips and provides the patient with a direct readout of the blood glucose level. Blood glucose monitors are effectively used in the home setting by diabetics. There is also a blood glucose monitoring system designed specifically for use by patients who are visually impaired. These monitors differ from the standard blood glucose monitor, as they have voice synthesizers, timers, and specific placement of supplies to enable the patient to use the equipment without assistance. Home self-monitoring of blood glucose enables certain diabetic patients to better control their blood glucose levels by frequently checking and appropriately contacting their physician for advice and

2 treatment. The following devices have received U.S. FDA approval for monitoring of glucose levels in the interstitial fluid: the Continuous Glucose Monitoring System (CGMS) (MiniMed), which uses an implanted temporary sensor in the subcutaneous tissues, and The GlucoWatch, an external device worn like a wristwatch that measures glucose in interstitial fluid extracted through the skin with an electric current (referred to as reverse iontophoresis). While the time intervals at which interstitial glucose is measured range from every 5 minutes (CGMS) to every 20 minutes (GlucoWatch), both types of monitoring have been referred to as continuous glucose monitoring. Both devices potentially eliminate or decrease the number of required daily fingersticks. However, it should be noted that (according to the FDA labeling) neither is intended to be an alternative to traditional self-monitoring of blood glucose levels. The devices serve as an adjunct supplying additional information on glucose trends that are not available from self-monitoring. It is anticipated that this information on glucose trends will lead to improved anti-diabetic regimens and ultimately normalization of hemoglobin A1C levels with a decreased risk of hypoglycemia. Both devices rely on the same chemistry, (i.e., the oxidation of glucose by glucose oxidase to produce hydrogen peroxide). Within the sensor, the hydrogen peroxide is further oxidized ultimately producing electrons and generating a measurable electric current which can be calibrated to the glucose concentration. The following discussion details other aspects of the two devices. 1. The GlucoWatch is similar in appearance to a wristwatch. A single use disposable component, called the AutoSensor, consists of a gel collection disk and a series of electrodes. The device automatically measures glucose every 20 minutes for a 12 hour period. After 12 hours the AutoSensor should be replaced. The device displays the most recent glucose level and can store the last 4,000 glucose readings along with their date and time. An audible alarm will sound if any reading is above a preset high or low level or if the reading is 35% or more below the previous reading. Each day, prior to use, the device must be calibrated with a fingerstick glucose test to allow for variability in skin permeability among individuals and at different skin sites. Although the noninvasiveness is an attractive quality of the device, it should be noted that the GlucoWatch is not intended to be used as an alternative to traditional fingerstick measures,

3 but rather as an adjunct. Specifically, it is recommended that changes in medication should not be prompted solely by a GlucoWatch measurement, but confirmed by a fingerstick blood glucose measurement. The FDA approved labeling for the GlucoWatch states in part: The GlucoWatch Biographer is a glucose monitoring device intended for detecting trends and tracking patterns in glucose levels in adults age 18 and older with diabetes. This device is intended for use by patients at home and in health care facilities. The GlucoWatch Biographer is intended for use as an adjunctive device to supplement, not replace, information obtained from standard home glucose monitoring devices. 2. The Continuous Glucose Monitoring System (CGMS) (MiniMed) consists of a subcutaneously implanted sensor that is attached to a small plastic disk the size of a dime and is taped to the skin to hold the sensor in place. A thin wire connects the sensor to a pager-sized glucose monitor which records and stores glucose values in memory. An electrical signal is continuously relayed to the glucose sensor, which records glucose levels every 5 minutes (some 288 values per day). For calibration purposes, the manufacturer recommends that the patient enter the results of four fingerstick blood glucose measurements per day into the monitor. The sensor is capable of transmitting values for up to three days, after which time it is removed and replaced with another if additional monitoring is needed. Unlike the GlucoWatch, the glucose values are not displayed, and thus cannot be used by the patient for self-monitoring. The data captured can be downloaded to a personal computer for review and use by a physician. The FDA approved labeling for the Continuous Glucose Monitoring System (CGMS) states in part: The CGMS is currently intended for occasional rather than everyday use is to be used only as a supplement to, and not a replacement for, standard invasive measurement. The CGMS is not intended to change patient management based on the numbers generated, but to guide future management of the patient based on response to trends noticed. That is, these trends or patterns may be used to suggest when to take the fingerstick glucose measurements to better manage the patient. Other techniques for continuous glucose monitoring include the use of both near and far infrared light spectroscopy to measure glucose levels transcutaneously. However, no such device has yet received FDA approval.

4 RATIONALE: Monitoring of glycemic status, as performed by patients and health care providers, is considered a cornerstone of diabetes care. Results of monitoring are used to assess the efficacy of therapy and to guide adjustments in medical nutrition therapy, exercise, and medications to achieve the best possible blood glucose control. Sustained improvement in blood glucose control is the only treatment outcome that will reduce or eliminate the long-term complications of diabetes mellitus. Although formal outcomes studies of home blood glucometer in diabetics not receiving insulin have NOT been formally evaluated, their use in ALL diabetics NOT achieving glycemic controls has been recommended by the 1998 American Diabetes Association clinical practice guidelines. The use of home glucometers may be a component of many diabetes disease management programs. The experimental or investigational status of devices to measure interstitial glucose levels is based on the lack of clinical data demonstrative that the use of these devices is associated with an improvement in final health outcomes, i.e., improved diabetic control, based either on decreasing hemoglobin A1C values and/or decreasing incidence of hypoglycemia. Data presented to the FDA advisory committee meeting consisted of studies validating the correlation between the measurements of glucose in interstitial fluid with the blood glucose measurements made with home monitoring devices. While the individual values between the two may vary, in general, the panel found that the overall trends in glucose levels detected by frequent measurements produced potentially clinically important information. However, there were no clinical data presented regarding improvements in hemoglobin A1C measurements or a decreasing incidence of hypoglycemic episodes in those whose antidiabetic medications were managed based on more frequent readings of interstitial fluid glucose. However, members of the advisory panel felt that more frequent measurements should extrapolate to improved diabetic management. For example, prior studies have shown that hemoglobin A1C levels are lowest among patients who have the highest frequency of daily blood glucose measurements. Nevertheless, the use of trends of daily glucose levels implies a different type of diabetic management compared to traditional methods of serial fingerstick glucose methods. The FDA advisory panels suggested the following clinical applications: Hypoglycemic episodes can be identified more readily by the use of an alarm in the GlucoWatch device. This may be particularly helpful in patients with hypoglycemic unawareness or overnight hypoglycemia.

5 In addition, patients with adequate glucose control, as measured by hemoglobin A1C, may undergo monitoring to ensure that this control does not come at the expense of unrecognized hypoglycemia. Unsuspected postprandial hyperglycemia may be detected, which contributes to elevated hemoglobin A1C concentrations in patients whose HbA1c levels are considered adequate. Postprandial hyperglycemia has been related to increased cardiovascular risks. Both fast-acting insulin (insulin lispro) and fast-acting oral hypoglycemics (i.e., repaglinide) may be particularly effective in treating postprandial hyperglycemia. The devices may be used periodically to confirm the status of current antidiabetic therapy. Currently, some patients may perform 7-9 finger sticks a day on a periodic basis to confirm the success of the diabetic management. Patients may use the devices in specific circumstances when the normal routine is upset, i.e. changes in work shifts or while traveling. The devices may be used to monitor changes in insulin therapy, i.e. the initiation of an insulin pump. The device may be used as an educational tool to more easily illustrate how glucose levels vary with activities and meal choices. Quality of life may be improved by decreasing the number of finger sticks. One pilot study focusing on glycemic control has been published. Bode and colleagues used a CGMS to assist in the diabetic management of 9 patients with type 1 diabetes and an HbA1C concentration greater than 8.5%. The participants used the CGMS for two one-week periods during the study. After each sensor use, changes to diet and insulin dosage were made. HbA1c values improved significantly over the 5-week period, while daily insulin requirement remained constant. The most common changes in diabetic management were alterations in diet and changes in the insulin schedule. PRICING: None

6 REFERENCES: Langer, O. and R. Mazze. "The relationship between large-forgestation-age infants and glycemic control in women with gestational diabetes." American Journal of Obstetrics and Gynecology (1988 December) 159(6): Texas Insurance Code Edition. Coverage for Supplies and Services Associated with Treatment of Diabetes. Article 21.53G Texas Insurance Code Edition. Texas Diabetes Care Pilot Program. Article 1. Vijan, S., et al. "Estimated benefits of glycemic control in microvascular complications in type 2 diabetes." Annals of Internal Medicine (1997 November 1) 127(9): American Diabetes Association. "Tests of glycemia in diabetes." Diabetes Care (1998) 21(Supplement 1): S69-S71. Halimi, S. "Benefits of blood glucose self-monitoring in the management of insulin-dependent (IDDM) and non-insulin-dependent diabetes (NIDDM). Analysis of the literature: mixed results." Diabetes and Metabolism (1998 November) 24 Supplement 3: Klein, R. and B.E. Klein. "Relation of glycemic control to diabetic complications and health outcomes." Diabetes Care (1998 December) 21(Supplement3): C39-C43. American Diabetes Association, Inc. "Implications of the diabetes control and complications trial. Position Statement. January 1999." Diabetes Care 22(s1): Harris, M.I., et al. "Racial and ethnic differences in glycemic control of adults with type 2 diabetes." Diabetes Care (1999 March) 22(3): "Blood Glucose Monitors (Glucometers)." BCBSA Consortium Health Plan Medical Policy Reference Manual (2002 April 15) Durable Medical Equipment: Continuous Monitoring of Glucose in the Interstitial Fluid. BCBSA Consortium Health Plan Medical Policy Reference Manual (2002 April 15) Durable Medical Equipment: Bode, B., et al. Continuous Glucose Monitoring used to adjust diabetes therapy improves glycosalated hemoglobin: a pilot study. Diabetes Research and Clinical Practice 46 (1999) 46: Tierney, M. J., et al. Clinical evaluation of the GlucoWatch biographer: a continual, non-invasive glucose monitor for patients with diabetes. Biosensors and Bioelectronics (2001 December) 16: Gross, T.M., et al. Performance Evaluation of the MiniMed continuous glucose monitoring system during patient home use. Diabetes Technology Therapy (2000 Spring) 2:

7 DISCLAIMER: State and federal law, as well as contract language, including definitions and specific inclusions/exclusions, takes precedence over Medical Policy and must be considered first in determining coverage. The member s contract benefits in effect on the date that services are rendered must be used. Any benefits are subject to the payment of premiums for the date on which services are rendered. Medical technology is constantly evolving, and we reserve the right to review and update Medical Policy periodically. HMO Blue Texas physicians who are contracted/affiliated with a capitated IPA/medical group must contact the IPA/medical group for information regarding HMO claims/reimbursement information and other general polices and procedures.