Guidelines

Clinical Guidelines and the Use of Continuous Glucose Monitoring (CGM) in the Management of Persons With Type 2 Diabetes.

Established clinical targets should be used to individualize glycemic targets and adjust therapy based upon each individual’s overall health status, concomitant medical condition (eg, pregnancy, frailty), and risk for hypoglycemia.

[AACE Recommendation 1.1.1; Grade C; Low-Intermediate Strength of Evidence1]

All Persons With Diabetes

  • Number of days of active CGM use: 14 days preferred
  • Percentage of data available from active CGM use: > 70% of data from 14 days
  • Mean glucose: Individualized to targets
  • Glucose Management Indicator (GMI): Individualized to targets
  • Glycemic variability, %CV: ≤ 36%

T1D/T2D

  • %Time in Range (TIR) 70 to 180 mg/dL:>70%
  • %Time Below Range (TBR)<70 mg/dL:<4%
  • %TBR<54 mg/dL:
  • %Time Above Range (TAR)>180 mg/dL:< 25%
  • %TAR>250 mg/dL:< 5%

Older/High Risk T1D/T2D

  • %TIR 70 to 180 mg/dL: > 50%
  • %TBR < 70 mg/dL: < 1%
  • %TBR < 54 mg/dL: ~0%
  • %TAR > 250 mg/dL: < 10%

Two metrics, %TIR and %TBR, should be used as a starting point for the assessment of quality of glycemic control and as the basis for therapy adjustment, with emphasis on reducing %TBR when the percentages of CGM values falling below 54 or 70 mg/dL are close to or exceed targets.

[AACE Recommendation 1.1.2; Grade B; Low-Intermediate Strength of Evidence1]

Older/High Risk T1D/T2D

  • CGM is strongly recommended for all persons with diabetes treated with intensive insulin therapy, defined as 3 or more injections of insulin per day or the use of an insulin pump.
    [AACE Recommendation 2.1.1; Grade A; High Strength of Evidence1]
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  • Structured self-monitoring of blood glucose (SMBG) is recommended for individuals on insulin therapy who have limited success with or are unable or unwilling to use CGM.
    [AACE Recommendation 2.1.2; Grade A; High Strength of Evidence1]

     

  • CGM is recommended for all individuals with problematic hypoglycemia (frequent/severe hypoglycemia, nocturnal hypoglycemia, hypoglycemia unawareness).
    [AACE Recommendation 2.1.3, Grade A; Intermediate-High Strength of Evidence1]
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  • CGM is recommended for pregnant women with T1D and T2D treated with intensive insulin therapy.
    [AACE Recommendation 2.1.5, Grade A; Intermediate-High Strength of Evidence1]

     

  • CGM may be recommended for individuals with T2D who are treated with less intensive insulin therapy.
    [AACE Recommendation 2.1.8, Grade B; Intermediate Strength of Evidence1]

[Note: Have not included recommendations related to children/adolescents with T1D or women with GDM since this project is focused on T2D; please advise if you wish to have these added]

Education and Training

  • When prescribing CGM devices, robust diabetes education, training, and support are required for optimal CGM device implementation and ongoing use. People using CGM devices need to have the ability to perform self-monitoring of blood glucose in order to calibrate their monitor and/or verify readings if discordant from their symptoms.
    [ADA Recommendation 7.8; Level of Evidence B2]
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  • Training of persons with diabetes should utilize a structured, comprehensive training program that covers all aspects of safe and effective use of diabetes technologies.
    [AACE Recommendation 4.2.1; Grade C; Low Strength of Evidence/Expert Opinion of Task Force1]
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Real-time CGM (rtCGM) and Intermittently Scanned CGM (isCGM)

  • When used properly, rtCGM in conjunction with multiple daily injections and continuous subcutaneous insulin infusion and other forms of insulin therapy are a useful tool to lower and/or maintain A1C levels and/or reduce hypoglycemia in adults and youth with diabetes.
    [ADA Recommendation 7.9; Level of Evidence A/C2]
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  • rtCGM should be recommended over isCGM to persons with diabetes with problematic hypoglycemia (frequent/severe hypoglycemia, nocturnal hypoglycemia, hypoglycemia unawareness) who require predictive alarms/alerts. However, the lifestyle of persons with diabetes and other factors should also be considered.
    [AACE Recommendation 2.3.1; Grade B; Intermediate Strength of Evidence1]
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  • When used properly, isCGM in conjunction with multiple daily injections and continuous subcutaneous insulin infusion and other forms of insulin therapy can be useful and may lower A1C levels and/or reduce hypoglycemia in adults and youth with diabetes to replace self-monitoring of blood glucose.
    [ADA Recommendation 7.10; Level of Evidence B/C2]
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  • isCGM should be considered for persons with diabetes who meet 1 or more of the following criteria:
    • Newly diagnosed with T2D
    • Treated with nonhypoglycemic therapies
    • Motivated to scan device several times per day
    • At low risk for hypoglycemia, although desire more data than SMBG provides
      [AACE Recommendation 2.3.2; Grade D; Low Strength of Evidence/Expert Opinion of Task Force1]
    • In patients on multiple daily injections and continuous subcutaneous insulin infusion, rtCGM devices should be used as close to daily as possible for maximal benefit. IsCGM devices should be scanned frequently, at a minimum once every 8 h.
      [ADA Recommendation 7.11; Level of Evidence A2]

     

    When to Consider Diagnostic/Professional CGM or Intermittent CGM Use

    • Diagnostic/professional CGM should be used in the management of persons with diabetes who meet 1 or more of the following criteria:
      • Newly diagnosed with diabetes mellitus
      • Not using CGM
      • May have problematic hypoglycemia, but no access to personal CGM
      • Persons with T2D treated with non-insulin therapies who would benefit from an episodic use of CGM as an educational tool
      • Persons who would like to learn more about CGM before committing to daily use
    • Importantly, in those using “masked” or “blinded” diagnostic/professional CGM, they must have and continue using adjunctive SMBG to assist in daily diabetes self-care.
      [AACE Recommendation 2.4.1; Grade B; Intermediate Strength of Evidence1]
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    • Use of professional CGM and/or intermittent rt-or isCGM can be helpful in identifying and correcting patterns of hyper- and hypoglycemia and improving A1C levels in people with diabetes on noninsulin as well as basal insulin regimens.
      [ADA Recommendation 7.13; Level of Evidence C2]
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    • Intermittent/occasional CGM may be recommended for the management of persons with diabetes who are reluctant or unable to commit to routine CGM use.
      [AACE Recommendation 2.5.1; Grade C; Intermediate Strength of Evidence1]
  • Ambulatory Glucose Profile (AGP) may be utilized to assess glycemic status in persons with diabetes.
    [AACE Recommendation 2.2.1; Grade B; Low Strength of Evidence1]
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  • When using AGP, a systematic approach to interpret CGM data is recommended:
    • Review overall glycemic status (e.g., GMI, average glucose)
    • Check TBR, TIR, and TAR statistics, focusing on hypoglycemia (TBR) first. If the TBR statistics are above the cut-point for the clinical scenario (ie, for most with T1D > 4% 1% Review the 24-hour glucose profile to identify the time(s) and magnitude(s) of the problem identified
    • Review treatment regimen and adjust as needed
      [AACE Recommendation 2.2.2; Grade B; Low Strength of Evidence1]
  • Skin reactions, either due to irritation or allergy, should be assessed and addressed to aid in successful use of devices.
    [ADA Recommendation 7.14; Level of Evidence E2]
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  • With the use of CGM, clinicians should make a reasonable effort to ascertain that a person with diabetes is not inadvertently ingesting a substance or medication that will cause the CGM to deliver false or misleading information. Furthermore, clinicians should make a reasonable effort to make persons with diabetes aware of the theoretical risk of radiation exposure to diabetes technologies.
    [AACE Recommendation 3.1.1; Grade C; Low Strength of Evidence/Expert Opinion of Task Force1]
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  • Persons with diabetes who have a care provider, such as a spouse, adult child of a geriatric person with diabetes, or parent of a child with diabetes, who remotely monitors glucose data, should be cautioned that remote glucose monitoring is dependent upon server functionality and that data interruption can result. Back-up plans of having persons with diabetes revert to SMBG or methods to communicate CGM data to those who remotely follow will be needed until functionality can be restored.
    [AACE Recommendation 3.1.2; Grade D; Low Strength of Evidence/Expert Opinion of Task Force1]

Consider including the following AACE guidelines:

  • The continuation of CGM and/or CSII (insulin pump, SAP, LGS/PLGS) should be considered in hospitalized persons with diabetes without cognitive impairment and ideally with the presence of a family member who is knowledgeable and educated in the use of these devices or with a specialized inpatient diabetes team available for advice and support.
    [AACE Recommendation 2.10.1; Grade A; Intermediate Strength of Evidence1]
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  • rtCGM is recommended for persons ≥ 65 years old with insulin-requiring diabetes to achieve improved glycemic control, reduce episodes of severe hypoglycemia, and improve QoL. However, glycemic goals should be individualized due to increased comorbidities and reduced capacity to detect and counter-regulate against severe hypoglycemia in this population.
    [AACE Recommendation 2.10.2; Grade A; Intermediate-High Strength of Evidence1]
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  • Telemedicine, including periodic phone calls, smartphone-web interactions, and periodic supervision by health care professional interactions, is strongly recommended to treat persons with diabetes, provide diabetes education, remotely monitor glucose and/or insulin data to indicate the need for therapy adjustments, and improve diabetes-related outcomes/control with better engagement.
    [AACE Recommendation 2.11.1; Grade A; Intermediate-High Strength of Evidence1]
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  • Initiation and use of diabetes technology should be implemented by health care professionals who are trained, committed, and experienced to prescribe and direct the use of these tools. Clinicians should have the infrastructure to support the needs of persons with diabetes using the technology.
    [AACE Recommendation 4.1.1; Grade B; Intermediate Strength of Evidence/Expert Opinion of Task Force1]

There are many places within the guidelines content that would be amenable to linking to other components of the Toolkit if desired, such as glossary terms, table of devices, step-by-step instructions for professional or personal CGM, and interactive AGP report/video, etc.

Guidelines

Grunberger G, et al. American Association of Clinical Endocrinology Clinical Practice Guideline: The Use of Advanced Technology in the Management of Persons with Diabetes Mellitus. Endocrine Practice. 2021;27:505-537. https://pubmed.ncbi.nlm.nih.gov/34116789/

American Diabetes Association. 7. Diabetes technology: standards of medical care in diabetes – 2021. Diabetes Care. 2021;44(S1):S85-S99. https://pubmed.ncbi.nlm.nih.gov/33298418/