Association Between Self-Monitored Blood Glucose and Continuous Glucose Monitoring in Youth with Type 1 Diabetes and Medicaid Insurance

Objective: Youth with type 1 diabetes (T1D) and Medicaid must demonstrate selfmonitored blood glucose (SMBG) at least four times daily to receive continuous glucose monitors (CGMs). New California Medicaid policies eliminated this requirement which have increased CGM access. This study examines whether infrequent baseline SMBG results in suboptimal outcomes or non-adherence with CGM use. Research Design and Methods: This retrospective study included youth with T1D and Medicaid who started CGM after January 2019, when newer models no longer needed calibration, at two large healthcare systems. Patients were stratified by baseline SMBG frequency (< 4 vs ≥ 4) collected at the clinic visit prior to starting CGM. Differences between SMBG groups in CGM adherence and HbA1c over time were assessed by a mixed effects linear regression model and fixed effect interaction term. Patients were surveyed to explore individual impact of CGM on diabetes management. Results: 78 youth were followed for 6 months. CGM adherence was similar between SMBG frequency groups at 3-months (68.7 vs. 68.4%, p=0.97) and sustained at 6months. HbA1c improved in both groups at 3-months, with a larger improvement in those with SMBG < 4 (1.3% vs 0.4%), and sustained at 6-months. Patient surveys (n=35) reported high engagement with CGM and increased insulin boluses after initiation. Conclusions: Patients on CGM demonstrated improvement in HbA1c regardless of prior SMBG. Increased engagement with CGM likely promoted increased insulin boluses. Therefore, restriction of CGM to those with SMBG ≥ 4 is an unnecessary barrier, excluding those who could potentially benefit the most.