Alterations in Regional Brain Structures Observed in Diabetes, Excluding Prediabetes
Overview
This study analyzed brain structural changes across diabetes (DM), prediabetes (PreDM), and normal controls, revealing significant gray matter volume (GMV) reductions and increased white matter hyperintensity (WMH) in DM but not in PreDM. These brain alterations in DM correlated with declines in cognitive function, gait speed, and grip strength, highlighting the impact of diabetes on cerebral architecture.
Background
Diabetes mellitus is increasingly recognized as a risk factor for cognitive dysfunction and dementia, potentially due to microvascular brain damage caused by hyperglycemia. While brain atrophy and white matter changes have been documented in DM, the extent to which these changes occur in the prediabetic stage remains unclear. Previous studies have shown mixed results regarding GMV reductions in PreDM, and the progression of tract-specific WMH in PreDM is not well understood. This study aims to clarify these relationships using advanced neuroimaging and clinical assessments across glycemic states.
Data Highlights
Group
Participants (n)
GMV Changes
WMH Index
Cognitive Scores (MoCA)
Gait Speed
Grip Strength (Right Hand)
Diabetes (DM)
122
Significant reductions in bilateral cerebellum, right precentral gyrus, left postcentral gyrus (P < .001)
Significantly higher across 20 tracts (P < .05, FDR-corrected)
Decreased (P = .04)
Decreased (P < .05)
Decreased (P < .05)
Prediabetes (PreDM)
109
No significant GMV changes detected
No significant WMH progression detected
No significant cognitive decline
No significant gait speed change
No significant grip strength change
Normal Controls (NC)
281
Baseline
Baseline
Baseline
Baseline
Baseline
Key Findings
Significant GMV reductions were observed in DM patients, particularly in regions related to movement and coordination such as the bilateral cerebellum, right precentral gyrus, and left postcentral gyrus.
DM patients exhibited significantly higher WMH indices across 20 white matter tracts, correlating positively with glycemic levels.
These brain structural changes in DM were associated with decreased cognitive performance (MoCA scores), slower gait speed, and reduced right-hand grip strength.
No significant GMV or WMH changes were detected in the PreDM group compared to controls, suggesting brain structural integrity is relatively preserved in prediabetes.
The findings challenge the assumption that brain structural decline begins gradually in PreDM, highlighting diabetes as a critical factor in cerebral alterations.
Clinical Implications
Clinicians should recognize that significant brain structural changes and associated functional impairments are primarily evident in established diabetes rather than in prediabetes. This underscores the importance of early diabetes prevention and management to protect cerebral integrity and cognitive and motor functions. Routine neuroimaging and cognitive assessments may be considered in diabetic patients to monitor brain health.
Conclusion
Diabetes is associated with marked alterations in regional brain structures and white matter integrity, correlating with cognitive and motor declines, whereas prediabetes does not show these changes. These results emphasize diabetes as a pivotal factor in cerebral deterioration rather than a gradual decline starting in prediabetes.
References
Changfeng Study Group/2024 -- Alterations in Regional Brain Structures Observed in Diabetes, Excluding Prediabetes
