The Impact of CGM on Type 1 Diabetes

Feb 8, 2025

Continuous Glucose Monitoring Systems for Type 1 Diabetes Mellitus

Overview

  • Study Title: Continuous glucose monitoring systems for type 1 diabetes mellitus
  • Authors: Miranda Langendam, Yoeri M. Luijfa, Lotty Hooft, J. Hans DeVries, Aart H. Mudde, Rob JPM Scholten
  • Version Published: January 18, 2012
  • Source: Cochrane Database of Systematic Reviews

Background

  • Type 1 Diabetes Management: Involves self-monitoring of blood glucose to optimize glycemic control.
  • Continuous Glucose Monitoring (CGM): Measures interstitial fluid glucose levels, offering semi-continuous glucose data and recognizing fluctuations not easily detected by conventional fingerprick self-monitoring.
  • Types of CGM Systems:
    • Retrospective systems
    • Realtime systems (provide current glucose concentration on display)

Objectives

  • To assess the effects of CGM systems compared to conventional self-monitoring of blood glucose (SMBG) in type 1 diabetes patients.

Research Methods

  • Databases Searched: Cochrane Library, MEDLINE, EMBASE, CINAHL
  • Selection Criteria: Randomized controlled trials comparing CGM with SMBG in type 1 diabetes patients.
  • Primary Outcomes: Glycemic control (HbA1c levels) and health-related quality of life.
  • Secondary Outcomes: Adverse events, complications, costs.

Main Results

  • Included Studies: 22 RCTs with 2883 patients.
  • Main Findings:
    • Significant decline in HbA1c for CGM users starting insulin pump therapy compared to MDI and SMBG users.
    • Mean difference in HbA1c: 0.7% reduction for CGM with pump, 0.2% for CGM alone.
    • Increased risk of hypoglycemia for CGM users; however, confidence intervals include a range of outcomes.
    • No significant difference in health-related quality of life between CGM and SMBG users.
  • Adverse Events: Severe hypoglycemia and ketoacidosis occurred infrequently.
  • Other Outcomes: Diabetes complications, death, and costs not measured.

Authors' Conclusions

  • Limited evidence supporting CGM effectiveness in children, adults, and poorly controlled diabetes patients.
  • Largest improvements observed in sensor-augmented insulin pump users.
  • Compliance with CGM use is critical for improving glycemic control.

Plain Language Summary

  • Type 1 Diabetes: Condition causing loss of insulin production, leading to elevated glucose levels and potential complications.
  • CGM Systems: Offer a more comfortable alternative to fingerpricks, providing continuous glucose data and trends.
  • Study Results: Decrease in HbA1c with CGM; low occurrence of adverse events like severe hypoglycemia and ketoacidosis.
  • Note: No data on pregnant women or those unaware of hypoglycemia.

Additional Information

  • Study Limitations: No measurement of certain outcomes such as diabetes complications, death, and costs.
  • Population Gaps: No studies focused on pregnant women or those with hypoglycemia unawareness.

References