P-346: Age at type 1 diabetes diagnosis independently predicts glycemic response to continuous glucose monitoring in a low-income population
S d S F Lemos, G L Torres, L P S Lima, J P A Freitas, N C Monteiro, M d L P Machado, L M Martins, B F d O Santos, T Trevisan, N O d SantanaAbstract
Introduction
Continuous glucose monitoring (CGM) access in Brazil remains limited and fragmented, with isolated initiatives that often prioritize specific subgroups. Identifying predictors of glycemic response may support more equitable prioritization strategies.
Objectives
To identify clinical and sociodemographic predictors of glycemic response to CGM use in individuals with type 1 diabetes (T1D).
Methods
A 6-month longitudinal study enrolled 53 individuals with T1D from a public endocrinology clinic in Northeastern Brazil. Patients were classified as responders if they achieved HbA1c equal to or below 7% and/or time in range equal to or above 70% at the end of follow-up. Participants without final HbA1c were classified based on time in range alone. Univariable analyses were performed for clinical, sociodemographic, and CGM engagement variables. Independent predictors were identified using Firth penalized logistic regression.
Results
A total of 32 (60.4%) of participants were under 25 years of age. The cohort was predominantly female (64.2%), with mean diabetes duration of 11±8.72 years. Of 53 participants, 21 were responders and 32 non-responders. Responders had lower baseline HbA1c [7.6% (6.6-8.4) vs. 9.8% (9.0-11.2); p<0.001] and older age at diagnosis [18.0 (9.0-24.0) vs. 11.0 years (6.8-15.0); p=0.006]. On multivariable analysis, only baseline HbA1c (OR 0.18, 95% CI 0.06-0.57; p=0.003) and age at diagnosis (OR 2.96, 95% CI 1.19-7.38; p=0.020) remained independent predictors. No associations were found with sex, BMI, depressive symptoms, or private health insurance.
Conclusions
Older age at T1D diagnosis and lower baseline HbA1c independently predicted glycemic response to CGM, suggesting that prioritization policies should consider adults with later-onset T1D, a group often overlooked in favor of pediatric populations. The predictive value of baseline HbA1c should be interpreted with caution, as it also served as part of the response criterion.