Continuous Glucose Monitoring vs Self-Monitoring of Blood Glucose for Type 1 Diabetes on Multiple Daily Injections
STEP 1 — Gather Information
Confirm diagnosis of type 1 diabetes, current insulin regimen (multiple daily injections), history of hypoglycemia or hypoglycemia unawareness, patient’s ability to use CGM device, access to supplies, and interest in real-time glucose data.
STEP 2 — Rule In / Rule Out
Rule in: Patient has T1D and is using MDIs. Rule out: Patient is not on MDIs (e.g., using insulin pump) or does not have T1D; if ruled out, consider alternative monitoring strategies per other guidelines.
STEP 3 — Classify or Stratify
Stratify by hypoglycemia risk: higher priority for CGM in patients with hypoglycemia unawareness, frequent nocturnal hypoglycemia, fear of hypoglycemia, or impaired awareness of hypoglycemia (IAH); lower priority but still recommended for all T1D on MDIs.
STEP 4 — Decide
Recommend initiating real-time CGM rather than SMBG by fingerstick; provide comprehensive CGM education and ensure continued access to SMBG for sensor validation, warm‑up periods, and symptom‑glucose mismatches.
Clinical Guardrails / Mimics / Pitfalls
Do not rely solely on CGM without SMBG backup; do not skip patient education on device use and troubleshooting; avoid CGM use if patient cannot afford supplies or has uncontrolled skin irritation from adhesives; remember that SMBG remains necessary for calibration/validation and during sensor warm‑up.
Concrete Clinical Example
A 22‑year‑old college student with T1D on MDI reports twice‑weekly nocturnal hypoglycemia and fear of sleeping; after CGM initiation with structured education, hypoglycemia episodes drop from 8 per month to 2, and SMBG is used twice daily to verify sensor accuracy.
Source: Management of Individuals With Diabetes at High Risk for Hypoglycemia: An Endocrine Society Clinical Practice Guideline, Endocrine Society, 2023, https://doi.org/10.1210/clinem/dgac596