Metabolic syndrome severity score associates with structural brain features and functional connectivity of Default Mode Network subsystems in the HABS‐HD study

• DOI: 10.1002/alz.091808
• Publication Date: 2025-01-09T11:48:11Z
• Authors: Zachary D. Green; Sid E. O'Bryant; Leigh A. Johnson; Jeffrey M Burns; Jill K Morris
• Keywords: Alzheimer's Imaging Consortium; Biomarkers

Abstract Background States of altered metabolic health such as syndrome (MetS), obesity, and insulin resistance increase Alzheimer’s Disease (AD) risk. Individuals with these conditions, like those AD, have demonstrated changes in the structural functional features Default Mode Network (DMN). Here, we characterize associations between systemic dysfunction, brain structure (Cortical Thickness Hippocampal Volume) connectivity DMN subnetworks. Method We leveraged data from Health Aging Brain Study: Disparities (HABS‐HD) dataset, an ongoing longitudinal study that characterizes AD biomarkers across diverse populations. Specifically, used initial visits Hispanic Non‐Hispanic White (NHW) cohorts. were categorized cognitively healthy (n=1192; age=66.1 years, 65% female) or impaired (n=307; age=67.4 50% female). a continuous measure risk (Mets‐Z) is more sensitive ethnicity‐specific than categorical definitions MetS. Mets‐Z weighted composite systolic blood pressure, triglycerides, HDL cholesterol, glucose, waist circumference. Structural measures acquired using FreeSurfer. Functional was measured via resting‐state fMRI, pre‐processed FSL. utilized both summary metrics (ROI‐based estimations) voxel‐wise approaches (FSL’s randomise). Result MetS‐Z differed diagnostic groups (t=‐2.387, p=.017) Hispanics NHWs (t=‐11.864, p<.001). Meta‐ROI cortical thickness negatively associated cognitive status (β = ‐.152, p < .001) ‐.085, .001). volume found to negative relationship (left, β ‐.073, .001; right, ‐.072, connectivity, specifically posterior DMN, significantly MetS‐Z. There high degree overlap clusters voxels which pDMN associated, demonstrating decreased due age status. Conclusion present evidence higher load ethnoracially cohort older adults, without impairment. Future studies should leverage HABS‐HD dataset examine if dysfunction predicts differences trajectory connectivity.