Key Takeaway


In patients with T2D and poor glycemic control receiving BI without prandial insulin, CGM vs BGM monitoring showed:

Significantly greater improvement in -8month HbA 1c level

Increased time in target glucose range of 70–180mg/dL

Reduction in both time spent at >250 mg/dL and mean glucose level

Why This Matters

Glucose monitoring is critical for safe and effective management of individuals with T2D using insulin
As the role of CGM in T2D using less-intensive insulin regimens is not well defined; present study compared CGM vs BGM monitoring in this study population.

Study Design


This Multicenter, Randomized (N = 175 [CGM Or BGM Group: 2:1]), Open - Label, Parallel - Group Trial Was Conducted At 15 Centers In The United States*

KEY INCLUSION CRITERIA

  • Age ≥30 years
  • T2D treated with 1 or 2 daily injections of long- or intermediate-acting basal insulin for ≤6 months
  • HbA 1c: 7.8%–11.5%
  • Self-reported BGM testing: ≥3 times per week
  • Smart phone compatible with CGM device†

STUDY OUTCOMES

  • Primary outcome: HbA1c level at 8 months (adjusted for BL value)
  • Key secondary outcomes:
    • Time in target glucose range of 70-180 mg/dL
    • Time at glucose level >250 mg/dL
    • Mean glucose level at 8 months (adjusted for BL value)

Key Results

A total of 175 participants were randomized (2:1) into CGM vs BGM group
(n = 116 vs 59; mean age = 57 years; mean BL HbA1c = 9.1%)

PRIMARY OUTCOME (CGM vs BGM GROUP):

  • HbA1c level at 8 months‡ 8.0% vs 8.4% (adjusted difference in mean change in HbA1c level from baseline:
    • -0.4% [%95 CI: %0.8− to %0.1−; P = 0.02])

KEY SECONDARY OUTCOMES (CGM vs BGM GROUP):

  • Time in target glucose range of 70-180 mg/dL (mean%): 59% vs 43% (adjusted mean difference: 15% [%95 CI: %8 to %23; P <0.001§])
  • Time at glucose level >250 mg/dL (mean%):11% vs 27% (adjusted mean difference: −16% [%95 CI: %21− to %11−; P <0.001¶])
  • Mean glucose levels at 8 months: 179 vs 206 mg/dL (adjusted difference: 26− mg/dL [%95 CI: 41− to 12−; P <0.001])
  • ADVERSE EVENTS: Severe hypoglycemic event (one in both, CGM and BGM group) and diabetic ketoacidosis (one in CGM group)
  • CGM satisfaction scale: Mean score (CGM group) = 4.1/5

Limitations

  • Follow-up duration was only 8 months
  • Due to virtual visits -8month HbA 1c or CGM data was not available for some participants
  • Limited generalizability of study findings to most routine clinical practice settings
  • In one-third of the CGM group HbA1c level still remained >%8 after 8 months highlighting the need for more aggressive pharmacological management

* Included participants not visiting an endocrinologist for diabetes and recruited participants from primary care practices.
† For data uploading.
‡ Adjusted for BL values (mean BL HbA1c level [CGM vs BGM group] = %9.1 vs %9.0).
§ Equivalent to 3.6 hours more per day.
Equivalent to 3.8 hours less per day.
# The study participants had greater contact with the clinic staff vs typical usual care scenario

ABBREVIATIONS:


BL, baseline; BI, basal insulin; BGM, blood glucose meter; CGM, continuous glucose monitoring; CI, confidence interval; HbA1c, hemoglobin A1c; T2D, type 2 diabetes.

    Martens T, Beck RW, Bailey R, Ruedy KJ, Calhoun P, Peters AL, et al. Effect of continuous glucose monitoring on glycemic control in patients with type 2 diabetes treated with basal insulin: A randomized clinical trial. JAMA. 2272–2262:(22)325;2021. doi: 10.1001/jama.2021.7444. PMID: 34077499.

MAT-BH-2300652/v1/October 2023