Intermittent CGM monitoring tied to higher HbA1c reduction compared to finger stick testing in T1 diabetes: NEJM

U.K. : According to study results published in The New England Journal of Medicine, intermittently scanned continuous glucose monitoring use is linked to larger reductions in HbA1c in type 1 diabetes at 24 weeks relative to finger-stick testing.

The implications of intermittently scanned continuous glucose monitoring with elective high and low blood glucose level alarms remain unclear in those with type 1 diabetes and high glycated hemoglobin levels.

"The findings of our study have broad ramifications for type 1 diabetes glucose monitoring," the researchers said.

"These advancements are predicted to lower the possibility of long-term diabetes problems and result in financial savings over time. We are doing a focused health-economic analysis that will support the recommendation of this therapy by international professional groups and policymakers," they added.

In the trial, the authors randomly assigned 156 adults (16 years and older) with type 1 diabetes in 1:1 ratio who had had the disease for at least a year and had a HbA1c between 7.5% and 11% to use the FreeStyle Libre 2 (Abbott) intermittently scanned CGM or to self-monitor their blood glucose levels using finger-stick testing for 24 weeks (mean age, 44 years; 97% white; 44% women). Seven diabetic clinics and one general care clinic in the UK were used to source participants. The primary analysis had 72 participants in the CGM group and 69 in the finger-stick group. Prior to randomization, all participants utilized CGM to collect baseline data for 10 to 14 days. At the screening, at 12- and 24-week intervals, HbA1c was assessed. The primary outcome at 24 weeks was a change in HbA1c. A blinded CGM was utilized from days 22 to 24 in the finger-stick group to measure individuals' time in range, duration of hypoglycemia and hyperglycemia, mean glucose, and glucose variability. The Type 1 Diabetes Distress Scale, Diabetes Fear of Injecting and Self-Testing Questionnaire, Fear of Self-Injection component, Diabetes Eating Problem Survey-Revised, Diabetes Treatment Satisfaction Questionnaire (DTSQ), Patient Health Questionnaire (9-item version), and Glucose Monitoring Satisfaction Survey were all completed by all participants (GMSS).

Key results of the trial:

• In comparison to the finger stick group, the CGM group exhibited a higher mean HbA1c at baseline (8.7% vs. 8.5%).
• At 24 weeks, the HbA1c in the CGM group fell to 7.9%, while the HbA1c in the finger-stick group fell to 8.3% (P<.001).
• Additionally, at 12 weeks, the CGM group's HbA1c was around 0.3 percen points lower than the group utilizing finger sticks.
• subjects using CGM were more likely to have a HbA1c of less than 7.5% at 24 weeks (adjusted OR = 2.47; 95% CI, 1.08-5.68) and to see an improvement in HbA1c of at least 0.5 percentage points (aOR = 4.74; 95% CI, 2.1-10.71) or 1 percentage point (aOR = 4.3; 95% CI, 1.67-11.09).]
• Comparing the CGM group to the finger-stick group, the CGM group spent 9% more time in range, 3% less time in hypoglycemia, and 6% less time in hyperglycemia.
• Additionally, compared to the finger-stick group, those using CGM scored higher on the DTSQ and the GMSS.
• For the remaining questionnaires, there were no additional differences found.

Future studies should concentrate on minimizing the burden of glucose alarms, the effect of socioeconomic deprivation on glycemic outcomes, reducing variation in access to technology, cost-effectiveness, and qualitative studies on the impact of glucose monitoring, concluded the investigators.

REFERENCE

Lalantha Leelarathna et.al., Intermittently Scanned Continuous Glucose Monitoring for Type 1 Diabetes; New England Journal of Medicine, 10.1056/NEJMoa2205650 [doi];https://www.nejm.org/doi/full/10.1056/NEJMoa2205650