1. The Internist’s Approach to Leveraging Continuous
Glucose Monitoring in Diabetes
This program is supported by an educational grant from Abbott Diabetes Care Inc.
Provided by Clinical Care Options, LLC
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About These Slides
Slide credit: clinicaloptions.com
3. Faculty
Martin J. Abrahamson, MD, FACP
Associate Professor of Medicine
Harvard Medical School
Director, Division of CME
Beth Israel Deaconess Medical Center
Boston, Massachusetts
Leslie Eiland, MD
Assistant Professor
Division of Diabetes, Endocrinology, and Metabolism
University of Nebraska Medical Center
Omaha, Nebraska
4. Disclosures
The faculty reported the following relevant financial relationships or
relationships to products or devices they have with ineligible companies
related to the content of this educational activity.
Martin J. Abrahamson, MD, FACP, has disclosed that he has received
consulting fees from Novo Nordisk, and WebMD Health Services.
Leslie Eiland, MD, has disclosed that she has received consulting fees for
Cecelia Health, Provention Bio, Roche, and Sanofi.
5. Program Agenda
CGM Technology
CGM Utilization
Patient Case Examples
Ensuring Success With CGM
Question and Answer Session
7. Primary Care Providers Take
Care of MOST People With Diabetes!
US Counties With ≥1
Pediatric or Adult Endocrinologist/Diabetologist
US Counties With ≥1
Primary Care Provider
Oser. Clinical Diabetes. 2020;38:188. Slide credit: clinicaloptions.com
8. SMBG vs CGM
SMBG
‒ Measures capillary blood glucose
‒ Provides sporadic data
‒ Provides a snapshot of blood glucose at a
single point in time
‒ Can be burdensome for PWD
CGM
‒ Measures interstitial glucose
‒ Provides real-time or retrospective blood
glucose data
‒ Provides insights into glucose trends so
PWD can act preemptively to avoid
hyperglycemia or hypoglycemia
‒ Increased ease of use
‒ Increased awareness of blood glucose levels
ADA. Diabetes Care. 2022;45:S1. Ajjan. Diabetes Technology & Therapeutics. 2017;19:S-27.
Longo. Diabetes Spectr. 2019;32:183. Slide credit: clinicaloptions.com
9. SMBG vs CGM
Slide credit: clinicaloptions.com
Transmitter
Glucose sensor measures
glucose in the interstitial fluid
BG meter measures
glucose in the blood
10. There Is a “Lag” Between Fingerstick and
Continuous Glucose Monitoring Levels
freestyle.com.au Slide credit: clinicaloptions.com
Blood glucose
CGM glucose
Glucose levels
6.8
mmol/L
6.9
mmol/L
7.2
mmol/L
9.4
mmol/L
9.4
mmol/L
7.8
mmol/L
When glucose levels
remain stable, CGM and
fingerstick levels are
similar
With rapidly rising
glucose levels,
CGM may be lower
than fingerstick levels
For rapidly falling
glucose,
CGM may be higher
than fingerstick levels
11. Real-Time vs Intermittently Scanned (Flash)
CGM Systems
rtCGM isCGM
Data transmission
Continuously transmits BG data
to a receiver/device
Measures BG continuously, but
transmitter must be manually
scanned to a reader or a phone to
access data
SMBG calibration Not all No
Remote data sharing Yes Yes
Option to use with insulin pump Yes No
Alarms Yes Yes
Treatment decisions without
confirmatory SMBG
Yes, most Yes
ADA. Diabetes Care. 2022;45:S1. Longo. Diabetes Spectr. 2019;32:183. Edelman. Diabetes Care. 2018;41:2265.
Hirsch. Role of Continuous Glucose Monitoring in Diabetes Treatment. 2018. Engler. Clinical Diabetes. 2018;36:50. Slide credit: clinicaloptions.com
12. Professional and Personal CGM Systems
▪ Belong to the HCP
▪ Provides data for the HCP and PWD
to review
▪ Educational tool
▪ Can help HCPs identify patterns for
insulin dose adjustments
▪ Can be blinded or unblinded
▪ Belong to the PWD
▪ Provide real-time continuous data
▪ Unblinded
Professional Personal
ADA. Diabetes Care. 2022;45:S1. Slide credit: clinicaloptions.com
13. Available Professional CGM Systems
CGM System Blinded
Sensor
Placement
Length of
Sensor Wear
SMBG
Reusable
Sensor
MARD, %
Medtronic iPro 2 Yes SC
Seven 24-hr
periods
Every 12 hr
for system
uploading
Yes 13.6
Dexcom G6 Pro Yes or no SC 10 days
None
required
No 9
FreeStyle Libre Pro Yes SC 14 days
None
required
No 12.3
Adapted from Longo. Diabetes Spectr. 2019;32:183. Chamberlain. Role of Continuous Glucose Monitoring in Diabetes
Treatment. 2018. Hirsch. Clin Diabetes. 2019;37:150. provider.dexcom.com/products/dexcom-g6-pro#key-features Slide credit: clinicaloptions.com
14. Available Personal CGM Systems
CGM System
Sensor
Placement
Length of
Sensor Wear
SMBG
Calibration
Approved for
Insulin Dosing
Insulin Pump
Integration
MARD, % Alarm
rtCGM
Dexcom G6 SC 10 days
None
required
Yes Yes 9 Yes
Medtronic Guardian
Sensor 3
SC 7 days ≥2x/day No Yes 9.6-10.5 Yes
Eversense Implantable 180 days ≥2x/day No No 8.8 Yes
isCGM
FreeStyle Libre SC 14 days
None
required
Yes No
10 days: 9.7
14 days: 9.4
No
FreeStyle Libre 2 SC 14 days
None
required
Yes No
Adults: 9.2
Children: 9.7
Yes
Longo. Diabetes Spectr. 2019;32:183. ascensiadiabetes.com/eversense/. FreeStyle Libre 2 User Manual. Slide credit: clinicaloptions.com
15. CGM Device Parts
Sensor + transmitter + receiver/monitor/reader device*
*Most CGM devices can use cell phone apps to receive glucose data.
Slide credit: clinicaloptions.com
17. Time in Range
TIR (70-180 mg/dL) correlates with diabetes complications
Lu. Diabetes Care. 2018;41:2370. Beck. Diabetes Care. 2019;42:400. Slide credit: clinicaloptions.com
Figure not available
18. Glucose Variability
GV: How much glucose levels vary from the mean glucose1
‒ <36% = stable glucose profile
‒ ≥36% = unstable glucose profile
Targeting GV can help guide safer treatment decisions vs focusing on A1C2
Increased GV is associated with:
‒ Greater risk of hypoglycemia (severity, duration, and frequency)3
‒ Long-term increases in microvascular and macrovascular complications3-5
‒ Decreased quality of life and mood6,7
1. Bergenstal. Role of Continuous Glucose Monitoring in Diabetes Treatment. ADA; 2018. 2. Umpierrez. Am J Med Sci.
2018;356:518. 3. Chehregosha. Diabetes Therapy. 2019;10:853. 4. Jung. Endocrinol Metab. 2015;30:167. 5. Hirakawa.
Diabetes Care. 2014;37:2359. 6. Penckofer. Diabetes Tech Therap. 2012;14:303. 7. Cox. Diabetes Care. 2007;30:2001. Slide credit: clinicaloptions.com
19. Glucose Variability Tells Us More Than A1C
These 3 people have an A1C of 7.0% and an average BG of 154 mg/dL…
Low Variability
180 mg/dL
70 mg/dL
12:00 AM 12:00 AM
12:00 PM
Moderate Variability
12:00 AM 12:00 AM
12:00 PM
180 mg/dL
70 mg/dL
High Variability
12:00 AM 12:00 AM
12:00 PM
180 mg/dL
70 mg/dL
…but very different glucose variability
100%
20%
40%
40%
Low
In range
High
70%
25%
5%
Slide credit: clinicaloptions.com
21. CGM Is Here to Stay
Provides so much more data than SMBG
There are different CGM “systems”
They all provide valuable information that is helpful for patients
and HCPs
The challenge is which ones to use and when and how to incorporate
them into your daily practice
5
/
2
9
/
2
0
2
3
2
1
23. Evidence for Intensive Insulin
Studies have shown clinical efficacy
of CGM in T1D regardless of insulin
delivery method
Significant reductions in
hospitalizations for acute diabetes-
related events and absenteeism
T2D has most data on isCGM;
A1C improvement is less consistent
than T1D, but reduction in
hypoglycemia is clear
CGM benefits for this group
‒ Improved glucose control
‒ Increased engagement with
diabetes care
‒ Relief from cumbersome and
intrusive fingersticks
‒ More information, better
control, less work
Grunberger. Endocrine Pract. 2021;27:505. Slide credit: clinicaloptions.com
24. MOBILE: CGM in Persons With
T2D Receiving Basal Insulin
Randomized, multicenter trial of CGM
vs BGM in adults with T2D receiving
basal insulin without prandial insulin
in primary care setting (N = 175)
‒ Primary outcome: A1C at 8 mo
‒ Secondary outcomes: TIR
(70-180 mg/dL), time >250 mg/dL,
mean glucose at 8 mo
Results: CGM demonstrated
significant improvement vs BGM
across all primary and secondary
outcomes
Martens. JAMA. 2021;325:2262. Slide credit: clinicaloptions.com
Cumulative
Distribution
A1C Level at 8 Mo (%)
100
80
60
40
20
0
≤5 ≤6 ≤7 ≤8 ≤9 ≤10 ≤11 ≤12 ≤13
Cumulative Distribution of 8-Mo A1C Values
CGM (n = 105)
BGM (n = 51)
25. MOBILE Follow-up: Discontinuing CGM
Reverses Benefit in T2D With Basal Insulin
6-mo extension study rerandomized MOBILE participants in CGM group
to continue or discontinue CGM and switch to BGM
Mean TIR Mean A1C
In adults with T2D on basal insulin using real-time CGM for 8 mo, discontinuing
CGM resulted in a loss of ~50% of initial TIR gain
Aleppo. Diabetes Care. 2021;44:2729. Slide credit: clinicaloptions.com
Baseline Mo 8 Mo 14
25%
50%
75% 9.5%
9.0%
8.5%
8.0%
7.5%
7.0%
Baseline Mo 8 Mo 14
Discontinue CGM Continue CGM BGM
B
A
26. ADA/AACE Recommendations for Personal CGM
Guideline Recommendations
Strongly
recommended
All adults on multiple daily insulin injections or pump1,2
Recommended
Adults on basal insulin1
Problematic hypoglycemia2
Children/adolescents with T1D2
Pregnant women (T1D and T2D) on intensive insulin2
GDM on insulin2
May be
recommended
GDM not on insulin2
T2D on less-intensive insulin2
1. ADA. Diabetes Care. 2022;45:S97. 2. Grunberger. Endocrine Pract. 2021:27:505. Slide credit: clinicaloptions.com
27. AACE Recommendations for
Real-Time and Intermittently Scanned CGM
Guideline Recommendations
Real-time Problematic hypoglycemia requiring predictive alarms/alerts
Intermittently
scanned
Newly diagnosed with T2D
Treated with nonhypoglycemic therapies
Motivated to scan device several times per day
Low risk for hypoglycemia, but desire more data than SMBG
1. Grunberger. Endocrine Pract. 2021:27:505. Slide credit: clinicaloptions.com
28. Selecting Candidates for Professional CGM
Are suspected of having undetected
hypoglycemic episodes
Are uncertain/concerned about
initiating CGM
Are undergoing a temporary
vulnerable period (eg, post
hospitalization)
Require adequate preoperative
glycemic control for elective surgeries
Have or are suspected of having A1C
inaccuracies (eg, renal disease or
hemoglobinopathy)
Require proof that there is no
prohibitive hypoglycemia
when seeking a driver’s or
professional license
Do not wish to pursue personal CGM
Do not qualify for/cannot afford a
personal CGM system
Professional CGM Can Benefit Patients Who:
Longo. Diabetes Spectr. 2019;32:183. Slide credit: clinicaloptions.com
32. Patient Challenges
Challenge Solution
Cost and coverage
Variable but improving
Payers are relaxing criteria to improve;
manufacturers offering start-up programs,
assistance programs
Psychosocial resistance
Trial period with samples (Hello Dexcom,
My FreeStyle)
Professional sensor trial (blinded vs unblinded)
Concerns about sensor
longevity, adhesion
Device-specific adhesion guides available
Slide credit: clinicaloptions.com
33. Let’s Discuss: Provider Challenges
Lack of EHR integration + additional web platform
Coverage inconsistent among payers and changing
Questions regarding reimbursement
Increased work for staff, need to train patients
Unclear who in the multidisciplinary team “owns” the process
Increased visit time to obtain and review data
Slide credit: clinicaloptions.com
34. Coverage
Varies among payers
DME vs pharmacy benefits
Preferred products and approved suppliers vary
Medicare A/B: recently relaxed restrictions to 1+ insulin injection/day
(from 3+), no longer need documentation about checking 4x/day
Medicare Advantage: still requires 3+ injections, proof of
4x/day checks x 30 days
Create a quick reference guide of most common insurers in the area
Slide credit: clinicaloptions.com
35. provider.dexcom.com/coding Slide credit: clinicaloptions.com
2022 CGM CPT Coding
CGM Services Codes and Descriptions Medicare
Physician Office
Fee Schedule
Medicare
Outpatient
Diabetes Center
Private Payer
(2021
Averages)
RVU,
Nonfacility
95249 Personal CGM—Start-up/Training
Ambulatory continuous glucose monitoring of interstitial tissue fluid via a subcutaneous
sensor for a minimum of 72 hours; patient-provided equipment, sensor placement,
hook-up, calibration of monitor, patient training, and printout of recording.
Bill only once during the time period that the patient owns the device.
$59.87
$56.85
APC 5733
$128 1.73
95250 Professional CGM
Ambulatory continuous glucose monitoring of interstitial tissue fluid via a subcutaneous
sensor for a minimum of 72 hours; physician or other qualified healthcare professional
(office) provided equipment, sensor placement, hook-up, calibration of monitor, patient
training, removal of sensor, and printout of recording.
Do not bill more than 1x/month.
$151.57
$121.35
APC 5012
$309 4.38
95251 CGM Interpretation
Ambulatory continuous glucose monitoring of interstitial tissue fluid via a subcutaneous
sensor for a minimum of 72 hours; analysis, interpretation, and report.
Do not bill more than 1x/month.
$35.30
Paid under
physician fee
schedule
$97 1.02
36. Clinic Logistics
Barrier Solution
Increased work for staff,
need to train patients
Quick-start guides may negate training
Online videos are a great resource
Unclear who in the multidisciplinary
team “owns” the process
Roles for registered nurses, pharmacy
Increased visit time to obtain/review
data, unfamiliar how to interpret data
AGP provides structured approach
Workflows can be implemented to get
data prior to visit
Slide credit: clinicaloptions.com
37. Implicit Bias
Racial disparities seen in diabetes tech use
Healthcare racism and implicit bias exist, even in well-meaning,
engaged HCPs
What are suggested changes to current systems that can improve access
and create equal opportunities?
‒ Equal access to technology education could empower patients to approach
HCPs and initiate technology
‒ Developing tailored, culturally sensitive approaches when discussing new
technology
‒ Introducing every patient to diabetes technology in a standardized, trackable
manner
‒ Designing prescription pathways for technology that lie outside the HCP
Agarwal. Diabetes Technol Ther. 2021;23:306. Slide credit: clinicaloptions.com
38. Conclusions
CGM is becoming a recommended tool for larger subsets of people
with diabetes
Payer coverage is improving
Creating new workflows for CGM takes some time but is rewarding in
terms of patient outcomes and clinic revenue
‒ Structured pathways, along with patient-centered approaches, are
needed to provide equitable access
39. Resources
ADCES guides—extensive,
separate personal and
professional guides
Consumerguide.diabetes.org
Providers.DiabetesWise.org
Putting CGM Into Practice
diabeteseducator.org