Incorporating CGM Into Clinical Decision Making Etie Moghissi, MD, FACE Clinical Associate Professor, David Geffen School of Medicine UCLA 1
Limitations of Current Glucose Monitoring Methods A1c Standard of care, however: The extent to which hypoglycemia and hyperglycemia occur are unknown Unknown glucose variability SMBG Provides glucose information for only points in time, however: Hypoglycemia and hyperglycemia are often missed Overnight data is impractical Logbooks are difficult to interpret Sources: BBC, US T1 Diabetes Exchange 2011, dq&a Q42011, ADC Category Revenue Estimates.
Both patient s A1C = 7.6%. Who is doing better? Frank Bill
Common Sources of Error in A1C Interpretation Directionality of Effect Source of Error Falsely elevated A1C Iron deficiency Anemia Hemoglobinopathies Race: African American, Hispanic, Asian Falsely low A1C Hemolysis Reticulocytosis Hemoglobinopathies Post-hemorrhage or post-transfusion Drugs: Iron, erythropoietin, dapsone Uremia Splenomegaly Rubinow KB, Hirsch IB. Reexamining metrics for glucose control. JAMA. 2011; 305: 1132-1133
Unknown Daily Glucose Fluctuations AGP graphs of four different T1 DM patients (each with an A1c of between 7.6 and 7.7%) 1 1. Dunn, Hayter, Doniger, Wolpert (2014). Journal of Diabetes Science and Technology. 8(4) 720 730. doi: 0.1177/1932296814532200
Glucose mg/dl Glucose variability is not apparent from A1C 400 360 320 280 Hyperglycemia Mean BG ( HbA 1c ) Patient A (A1C = 7.8%) Patient B (A1C = 7.8%) 240 200 160 120 80 40 Hypoglycemia 0 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 Time (hrs) Image adapted from Penckofer et al. Diab Tech Ther 2012;14:303 10 7
PROFESSIONAL SOCIETY CGM GUIDELINES AACE/ACE 2016 Guidelines All patients with type 1 diabetes should use CGM CGM should be offered to all type 2 diabetes patients on multiple insulin injections, basal insulin, or sulfonylureas CGM should also be used in patients at risk for hypoglycemia and/or have hypoglycemia unawareness ADA 2016 Guidelines Adults: Patients with Type 1 diabetes and those with hypoglycemia unawareness or frequent hypoglycemic episodes Adults (ages 65+): Patients who have been successfully using CGM should continue to have access after age 65 ENDOCRINE SOCIETY 2015 CGM Medicare Bill S. 804 Adults: Recommended for type 1 patients with A1C of >7 who are able to wear the devices on a daily basis or who experience hypoglycemia Adults (ages 65+):Recommended for all patients who: o Take multiple daily injections or use an insulin pump o Unable to achieve glycemic control o Had previously been using CGM *For eligible Medicare beneficiaries As of January 2017, therapeutic CGM system is now covered by Medicare*
Professional CGM Type of CGM Primarily owned by Professional CGM Clinician Purpose Facilitate treatment adjustments, patient coaching and education through analysis of patterns and trends of captured data Type of data Retrospective Key insights data can provide Snapshot of progress Need for therapy adjustment Glucose patterns
Rationale for Retrospective CGM Indications for retrospective CGM 1 HbA1c above target with suspected post meal hyperglycemia or under utilization of insulin/oral medication Hypoglycemia, hypoglycemic unawareness Value of retrospective CGM utilization 2 Provision of actionable information on patterns and trends, regardless of underlying therapy
Professional CGM Options Professional CGM G4 Platinum Professional 1 7-day sensor wear Minimum twice daily fingerstick calibrations Patient wears sensor, transmitter and receiver Equipment disinfection after each use ipro 2 2 6-day sensor wear 3 to 4 daily finger-stick calibrations Patient wears sensor and transmitter Equipment disinfection after each use 1. http://hcp.dexcom.com/resources Retrieved November 2016 2. http://www.professional.medtronicdiabetes.com/resources-download-library Retrieved January 2017 Free Style Libre Pro 14 day sensor wear No need for daily fingerstick calibrations Sensor is applied to the back of the upper arm and activated during an office visit. Patient wears the sensor up to 14 days without any interaction with the device. 3-SCAN IN Sensor is scanned at the next visit.
How the FreeStyle Libre Pro System works 1 1 2 3 4 Application Recording Download Interpretation HCP applies a sensor onto patient at clinic. Sensor is worn for up to 14 days and records glucose readings continuously. Patient returns to the clinic. HCP scans the sensor to download the glucose data. Reports generated from the data are interpreted by an HCP and used in patient consultation. <5 min* Up to 14 days <5 min* ~10 min* Reimbursable under CPT 95250 Reimbursable under CPT 95251 1. FreeStyle Libre Pro Operator s Manual *Estimated time
Personal CGM 13
Available Glucose Sensors Type of CGM Abbott Freestyle Libre Medtronic Enlite Guardian Sensor 3 Dexcom 4, 5, 6 Calibration necessary? No Yes Yes Sensor duration 10 days 6 days 7 days Audible alerts for high and low glucose No Yes Yes Trend arrow displayed? Yes Yes Yes Connectivity to insulin pump No Yes Soon Start-up cost of system $360 (3 sensors, 1 reader) $567 (5 sensors) $790 (Receiver, transmitter and 4 sensors)
Basic Principles of CGM (AGP-Ambulatory Glucose Profiling) Interpretation Displays time of day when BG levels are highest or lowest Displays time of day with greatest variability and magnitude of variability A1C estimation is based on average daily BG readings. Note the wide range of mean glucose based on A1C levels Variability BELOW medium is high, suggesting trending towards hypoglycemia 10 % curve drops below 70 mg/dl Always fix hypoglycemia before addressing hyperglycemia
Time in Range As a general rule, patients with > 50 time in range will have an A1C < 7 % Range target is 80-180 mg/dl Below 80 mg/dl should be < 3 % of total values
Real Patient Case Study 2 Darryl H. Darryl H. is a 53 year old male, diagnosed Type 2 DM 9 years ago. When Darryl was seen in Februrary, he had an HbA1c greater than 15%. His BMI was 24.5. Darryl started on Tresiba at 50 units and Trulicity at 1.5 mg/week plus Metformin. 3 months later his HbA1c is 8.8% The case study provided is intended to be used for educational purposes only. Individual symptoms, situations and circumstances may vary.
Real Patient Case Study 2 Darryl H. The case study provided is intended to be used for educational purposes only. Individual symptoms, situations and circumstances may vary.
Contributing Factors to Glycemic Variability 1 Food choices Medications Activity Other factors Stress Sleep (shift workers) Illness or infections Other medications 1 Brownlee & Hirsch Glycemic variability: a hemoglobin A1c-independent risk factor for diabetic complications. JAMA 2006;295:1707 1708 doi:10.1001/jama.295.14.1707
Real Patient Case Study 1 Christopher M. Christopher M. is a 30 year old male, diagnosed Type 1 DM 10 years ago. Christopher was on an insulin pump for three years, not well controlled, decided to go on MDI. On Tresiba 10 units and Humalog with meals I/C: 1/10, CF: 1/60. His HbA1c 7-7.7% and his BMI was 18.6. SMBG < 70 mg/dl before meals. The case study provided is intended to be used for educational purposes only. Individual symptoms, situations and circumstances may vary.
Real Patient Case Study 1 Christopher M. (before) The case study provided is intended to be used for educational purposes only. Individual symptoms, situations and circumstances may vary.
Real Patient Case Study Christopher M) The case study provided is intended to be used for educational purposes only. Individual symptoms, situations and circumstances may vary.
Chris on Personal CGM
42 year old teacher T2DM x 5 years How would you interpret this glucose log? A1C 7.6 % How would you safely and effectively adjust his medical regimen? Meds: Metformin 500 mg BID Basal insulin 20 units
Value of CGM In Patients With T2DM Discover previously unknown hyper and hypoglycemic events Measure glycemic control directly rather than via the surrogate metric of A1C Observe metrics such as glycemic variability, time spent within, below or above targeted glucose range throughout the day Determine the duration and severity of unrecognized hypoglycemia, especially nocturnal Provide actionable information derived from the CGM report Initiate safe and effective management of patients undergoing hemodialysis Analyze glucose effects of targeted pharmacologic interventions (both fasting and postmeal glucose values) Determine the individualized duration of action of glucose lowering therapies Evaluate the effect of exercise on glycemic control Provide behavioral interventions based on real-time glycemic values Vigersky R, et al. Journal of Diabetes and Its Complications, Volume 31, Issue 1, 280-287.
Bob Age 48 Duration of T2DM 9 years Before After A1C 8.7 % 7.4% Meds Metformin 500 mg BID BG Monitoring Finger sticks AGP Symptoms Fatigue, paresthesias, Metformin 500 mg BID + IDeg Lira 30 units daily None
Bob Before CGM After CGM
Robin 67 year old woman with T2DM for 10 years Current meds: Glargine U300 14 units at 9 PM daily Linagliptin 5 mg q d A1C= 9 % Change Glargin to degludec DC Linagliptin Begin Liraglutide 0.6 u q am Download in 2 weeks
Brent Brent S. is a 53 y.o. male who presents with Diabetes out of control Hx. of prediabetes for 6 years has been on Metformin 500 mg/day In December A1c was 8% and recently 8.9%. Wants to change his life style before considering injectable Rx. Empagloflozin was added to metformin and given Libre personal CGM F/ U 2 weeks later 29
William 56 yo man with history of diabetes For 10 years on Metformin 2000 mg/ day. Glipizide 20 mg/day A1C 9% No known complications Has refused to go on injectable RX. Not convinced he needs it! SGL2 inhibitor was added to his regimen and started on Libre
Do you think he changed his mind after seeing his glucose pattern? 31
Summary CGM Technologies allow us to go beyond A1C, detect hypoglycemia, minimize glucose variability and adjust our therapy based on REAL DATA!
Thank You!