Glycemic Control and Longitudinal Brain MRI in Children Diagnosed with Diabetes before 3 Years of Age (CLARiFY Study)

Though early childhood onset of type 1 diabetes (T1D) is associated with brain development alterations, the affected brain regions and role of glycemic control are unknown. We aimed to examine associations between of HbA1c mean and variability and brain structure in a cohort of children diagnosed with T1D before 3 years of age. We recruited children presenting to a tertiary hospital in Australia from 1990-1992 in the Cognition and Longitudinal Assessment of Risk Factors over 30 Years (CLARiFY) Study. HbA1c was serially measured over 30 years after T1D diagnosis. Brain MRI was performed at ~12- and 30-years post diagnosis. We used linear mixed effects modelling to examine associations between mean HbA1c and HbA1c coefficient of variation and brain MRI structural measures. Data were available for 10 subjects (6 female). The mean age of diabetes diagnosis was 1.9 years. The mean HbA1c at 12- and 30-years post diagnosis was 8.5%. We did not find an association between mean HbA1c and any of the brain structures. Greater HbA1c coefficient of variation was associated with less sub-cortical gray matter volume (β=-41537, p=0.006) and greater cortical thickness (β=0.47, p=0.02) but not other brain structure measures (Table 1). In these preliminary analyses, we found HbA1c variability associated with measures of gray matter. Work is ongoing to confirm and understand the implications of these results. Disclosure C.Moran: None. O.Gbadeyan: None. A.Brown: None. S.A.Sakowski: None. V.Srikanth: None. F.Cameron: None. E.A.Northam: None. E.L.Feldman: None. R.Beare: None. Funding National Institutes of Health (R01DK129320)