Takahiko Kawamura, Toshitaka Umemura, Rui Imamine, Hiroyuki Umegaki, Naoko Kawano, Asako Mizoguchi, Mariko Kawai, Makiko Minatoguchi, Minoru Kusama, Yu Kouchi, Atsuko Watarai, Akio Kanai, Eitaro Nakashima and Nigishi Hotta
Background: We investigated what factors were associated with brain atrophy in elderly patients with type 2 diabetes.
Methods: We evaluated hippocampal and whole brain atrophy with automatic voxel-based morphometry of structural magnetic resonance image (MRI), voxel-based specific analysis regional analysis for Alzheimer’s disease (VSRAD), in 70 diabetic subjects and 35 non-diabetic subjects. Cognitive function tests – MMSE, word recall (immediate and delayed), Digit Symbol Substitution test (DSST), and Stroop Color Word (Stroop) test were performed. Cerebral small vessel disease (SVD) was diagnosed as silent brain infarct and white matter lesions (WMLs) according to MRI.
Results: Significantly stronger hippocampal and whole brain atrophy were observed in diabetic patients than non-diabetic subjects. The levels of glycosylated hemoglobin A1c were significantly correlated with indices of hippocampal and whole brain atrophy. In diabetic subjects, hippocampal atrophy was independently associated with age, albuminuria, serum intercellular adhesion molecules -1 levels and lower diastolic blood pressure, while whole brain atrophy was associated with age and subcortical WMLs grade. Regarding an association between albuminuria and brain atrophy, significant hippocampal and whole brain atrophy were found in patients with albuminuria after adjusting for confounders. Hippocampal atrophy was independently associated with word recall and Stroop test after adjustment, while whole brain atrophy was also associated with word recall, DSST, and Stroop test, although the association weakened after adding degree of SVD to the variables.
Conclusions: Albuminuria was an independent risk factor for brain atrophy, especially hippocampal atrophy, which was associated with cognitive impairment, suggesting that the management of albuminuria may prevent progression of brain atrophy resulting in cognitive decline. In addition, the usefulness of VSRAD to support diagnosis of cognitive decline associated with brain atrophy was shown in daily clinical setting.