TOPLINE:

Frequent use of continuous glucose monitoring (CGM) was associated with larger and more durable A1c reductions than CGM nonuse in patients with type 2 diabetes (T2D) on diverse medications, particularly when CGM was used for more than 270 days per year. 

METHODOLOGY:

• Previous research indicates that CGM should be used at least 70% of the time to achieve optimal glycemic control; however, the relationship between CGM frequency and glycemic control with the use of different medications has not been explored.
• Researchers conducted a retrospective, cross-sectional study to investigate whether the frequency of CGM use is associated with changes in A1c levels over 1 year in 9258 patients with T2D (mean age, 55.9 years; 45.4% women; baseline A1c levels, 7%-15%) treated with different therapies.
• CGM users were propensity-score matched to patients not using CGM (n = 4629 in each group); CGM users were classified into four groups according to frequency of use over 12 months: frequency 1 (≥ 1 to ≤ 90 days), frequency 2 (> 90 to ≤ 180 days), frequency 3 (> 180 to ≤ 270 days), and frequency 4 (> 270 days).
• Data were collected from insurance claims and electronic medical records from January 2019 to December 2023, including a 6-month baseline period prior to each patient’s first CGM sensor claim (index date) and a follow-up period of 12 months.
• The primary outcome was the change in A1c levels over the 12-month post-index follow-up period, assessed at baseline and approximately 3, 6, 9, and 12 months; secondary outcomes were the differences in the use of medications (prandial insulin, basal insulin, GLP-1 receptor agonists, and SGLT2 inhibitors) among frequency groups 1 and 4 and the CGM-nonuse group during follow-up.

TAKEAWAY:

• Greater reductions in A1c levels from baseline were observed in the high frequency group (> 270 days) than in the CGM-nonuse group at all time points, with the most pronounced reductions occurring 12 months after CGM initiation (mean difference, -1.52 percentage points; 95% CI, -1.73 to -1.32 vs -0.63 percentage points; 95% CI, -0.80 to -0.45).
• Early glycemic improvements were evident across all CGM frequency groups at 3 months, with those using CGM for more than 270 days a year showing the largest reduction compared with the CGM-nonuse group (mean difference, -0.91 percentage points; 95% CI, -1.12 to -0.70 vs -0.28 percentage points; 95% CI, -0.47 to -0.09).
• Patients with CGM use frequency of > 90 to ≤ 180 days and of > 180 to ≤ 270 days showed no additional glycemic improvement after 6 months.
• Only a frequency of more than 270 days of CGM use vs nonuse was associated with significant reductions in A1c levels at 12 months after the addition of GLP-1 receptor agonists, SGLT2 inhibitors, basal insulin, and prandial insulin therapy (P < .001 for all), with a more pronounced effect observed with GLP-1 receptor agonists.

IN PRACTICE:

“The current study, together with other research, strengthens the emerging evidence that CGM may serve as a valuable nonpharmacologic intervention in the management of type 2 diabetes,” an expert wrote in an invited commentary.

SOURCE:

The study was led by Irl B. Hirsch, MD, University of Washington Medical School of Medicine, Seattle. It was published online in JAMA Network Open.

LIMITATIONS:

The absence of A1c values in the electronic medical records limited the number of patients eligible for analysis. Insurance claims lacked detailed information on the types of prescribed CGMs, patient adherence patterns, and CGM downloads. The random selection of index dates for CGM nonuser patients during the 4-year observation period may have introduced bias. 

DISCLOSURES:

This study was funded by Roche Diagnostics. Three authors disclosed being employees of the funder. Some authors reported receiving personal fees, grants, or consulting fees from various sources unrelated to the submitted work, with one of the authors having a patent.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.