A Stepwise Approach to CGM Data Interpretation

Use of continuous glucose monitoring (CGM) in people living with type 1 and type 2 diabetes, particularly those with type 2 diabetes treated by primary care physicians, has expanded rapidly.

With limited time during primary care visits, the need for tools to interpret CGM data quickly and efficiently and use those data to adjust diabetes therapies is great.

To provide a simple, systematic method for CGM data interpretation, Emily D. Szmuilowicz, MD, and Grazia Aleppo, MD, created a stepwise approach published in the journal Postgraduate Medicine.¹

This approach has three key steps. Before diving into the steps and the tools to complete them, first ensure there is enough data to provide a reliable interpretation. The International Consensus on Time in Range recommends at least 70% of data is captured from two or more weeks of sensor wear.²

After sufficient data are confirmed, the following steps can be performed:

Step 1: What is the problem?

• Use CGM metrics: time in range (TIR)
• Identify hypoglycemia, hyperglycemia, or both

Step 2: Where is the problem?

• Use Ambulatory Glucose Profile (AGP)
• Locate if patterns exist and times of day

Step 3: How to adjust therapy?

• Use daily glucose data
• Determine the impact of food, medication, physical activity, etc.
• Recommend therapeutic modification for repeated patterns

Prioritize assessing and addressing hypoglycemia first, followed by fasting and/or postprandial hyperglycemia. A flowchart is provided in the publication for guidance on therapeutic modifications based on hypo- and hyperglycemia patterns.

To enable a clear assessment of the impact of a therapeutic change and empower the patient to make the change, the authors recommend addressing only one CGM pattern per visit.

Watch the video presentation by Dr. Aleppo to learn more about this approach to AGP interpretation.