Effect of CGM Access Expansion on Uptake Among Patients on Medicaid With Diabetes

Abstract

Objective: Current studies on continuous glucose monitor (CGM) uptake are revealing for significant barriers and inequities for CGM use among patients from socially underprivileged communities. This study explores the effect of full subsidies regardless of diabetes type on CGM uptake and HbA1c outcomes in a U.S. adult patient population on Medicaid.

Research design and methods: This retrospective cohort study examined 3,036 adults with diabetes enrolled in a U.S. Medicaid program that fully subsidized CGM. CGM uptake and adherence were assessed by CGM prescription and dispense data, including more than one fill and adherence by medication possession ratio (MPR). Multivariate logistic regression evaluated predictors of CGM uptake. Pre- and post-CGM use HbA1c were compared.

Results: CGM were very well received by both individuals with type 1 diabetes and individuals with type 2 diabetes with similar high fill adherence levels (mean MPR 0.78 vs. 0.72; P = 0.06). No significant difference in CGM uptake outcomes were noted among major racial/ethnic groups. CGM use was associated with improved HbA1c among those with type 2 diabetes (-1.2% [13.1 mmol/mol]; P < 0.001) that was comparable between major racial/ethnic groups and those with higher fill adherence achieved greater HbA1c reduction (-1.4% [15.3 mmol/mol]; P < 0.001) compared with those with lower adherence (-1.0% [10.9 mmol/mol]; P < 0.001).

Conclusions: CGM uptake disparities can largely be overcome by eliminating CGM cost barriers. CGM use was associated with improved HbA1c across all major racial/ethnic groups, highlighting broad CGM appeal, utilization, and effectiveness across an underprivileged patient population.

Graphical abstract

Figure 1

CGM adherence by diabetes and race/ethnicity. CGM fill adherence was assessed by MPR. Violin plot of MPR by diabetes type (A) and major race/ethnicity groups for those with type 2 diabetes (B). P values by t test and ANOVA depicted, respectively. Hispanic-Eng, Hispanic English-speaking; Hispanic-Span, Hispanic Spanish-speaking.

Figure 2

HbA_1c change by diabetes and race/ethnicity. Bar plots and continuous distribution plots of post-CGM vs. pre-CGM HbA_1c difference by diabetes type (A) and race/ethnicity for those with type 2 diabetes (B). Error bars represent 95% CI. P values of pairwise t tests depicted. Sample size for patients with available pre-CGM and post-CGM HbA_1c (type 2 diabetes, n = 221; type 1 diabetes, n = 87). Hispanic-Eng, Hispanic English-speaking; Hispanic-Span, Hispanic Spanish-speaking.