ESPE Abstracts

Background: The Korean National Health Insurance Service has started reimbursing the cost of continuous glucose monitoring (CGM) in type 1 diabetes (T1D) in 2019. We investigated the effect of CGM use on glycemic control among Korean children, adolescents, and young adults with T1D in a real-world setting.

Method: We retrospectively reviewed the medical records of childhood-onset T1D patients aged < 30 years (n = 448) at the last follow-up at Seoul National University Children's Hospital between January 2020 and June 2021. Among 297 patients who had received CGM prescription, 187 patients used CGM for more than 3 months. After excluding 21 patients with missing glycosylated hemoglobin (HbA1c) values, 166 patients (56 males and 110 females) were included in the final analysis. Glycemic control was assessed by HbA1c and CGM metrics, including the time CGM is active (tCGM).

Results: Greater than 70% use of CGM over 3 months (≥70% tCGM group) was more frequently achieved in patients with a diabetes duration < 1 year than those with a duration ≥ 1 year (100% vs. 65.9%, P=0.001). When we analyzed 129 patients with a diabetes duration ≥ 1 year (17.4 ± 5.9 years of age; 8.4 ± 5.7 years of diabetes duration; 82 real-time CGM and 47 intermittently scanned CGM users), ≥70% tCGM group (n = 85) showed significantly higher time in range (54.8% vs 44.7%, P=0.003), and lower HbA1c (7.5% vs 8.2%, P=0.004) and time above 250mg/dL (15.1% vs 24.8%, P=0.003) compared to <70% tCGM group (n = 44) at 3 months after CGM initiation. When we further investigated ≥70% tCGM group, HbA1c was significantly decreased from 8.1% to 7.5% at 12 months (P=0.006). HbA1c lowering effect was evident at the first 3 months of CGM use and maintained throughout 1 year (P<0.001). Time in range (from 52% to 59.6%, P=0.002), time below 54mg/dL (2.2% to 1.3%, P=0.028), time above 250mg/dL (17.3% to 12.4%, P=0.021) significantly changed from baseline to 12 months of CGM use.

Conclusion: Appropriate and continuous CGM use resulted in significant improvement in glycemic control in youth with T1D. Educating patients to keep the recommended “time CGM is active (≥70% use of CGM)” is important for better glycemic outcomes.