Brain structural andfunctional differences between Type II Diabetes Mellitus patients and healthy controls

Abstract

Type 2 diabetes mellitus (DM2) is related to cognitive impairments and increased risk for dementia. Neuroimaging studies have demonstrated DM2-related brain structural and functional changes which are partly associated to the cognitive decline. In this study, different image analysis techniques were applied to a cohort of 163 DM2 patients compared to 53 healthy controls. Structural studies were used to evaluate atrophy and loss of grey matter volume in cortical and subcortical areas, while the extraction and comparison of resting state networks (RSNs) was used to study the changes of synchronization of different networks and established as markers of the brain’s functionality assuming the association each networks to certain functions. The results found should be helpful to establish a relationship between the structural and functional effect of DM2, and a connection with atrophy patterns of dementias that have been proved to be somehow related. In addition, a machine learning approach was used to rank all the image analysis techniques applied based on how well they reflect DM2 effect, obtaining a result that could be taken into account by clinicians to establish priorities in their imaging methods. DM2 patients showed a significant loss of grey matter in cortical areas as well as a significant increase of synchronization in 4 RSNs, specifically in areas overlapping grey matter atrophy. Similarities were found between the DM2 atrophy pattern and the frontotemporal dementia (FTD) atrophy pattern, suggesting a greater affectation in executive functions rather than other cognitive areas like memory.