Frontal gray matter atrophy in middle aged adults with type 1 diabetes is independent of cardiovascular risk factors and diabetes complications

AimsTo determine if regional gray matter volume (GMV) differences in middle-aged adults with and without type-1 diabetes (T1D) are localized in areas most vulnerable to aging, e.g. fronto-subcortical networks; and if these differences are explained by cardiovascular risk factors and diabetes complications.MethodsRegional GMV was computed using 3 T MRI of 104 adults with a childhood onset of T1D (mean age: 49 ± 7 and duration: 41 ± 6 years) and 151 adults without diabetes (mean age: 40 ± 6). A Bonferroni threshold (n = 45, p ≤ 0.001) was applied to account for multiple between-group comparisons and analyses were repeated in an age- and gender-matched subset of participants with T1D and controls (n = 44 in each group, mean age [SD] and range: 44.0, [4.3], 17.4 and 44.6 [4.3], 17.0, respectively).ResultsCompared to controls, T1D patients had smaller GMV in the frontal lobe (6% to 19% smaller) and adjacent supramarginal and postcentral gyri (8% to 13% smaller). Between-group differences were independent of age, waist circumference, systolic blood pressure, fasting total cholesterol and smoking status and were similar in sensitivity analyses restricted to age- and gender-matched participants. Associations between GMV and diabetes complications were not significant.ConclusionsThese findings extend the notion of accelerated brain aging in T1D to middle-aged adults. The pathophysiology of frontal gray matter atrophy and its impact on future development of disability and dementia need further study, especially as middle-aged T1D patients progress to older age.