A new study has revealed that type 2 diabetes is linked to thinning of the brain’s cortex in older adults, with the most pronounced effects seen in Hispanic individuals. Researchers from the Keck School of Medicine at USC and collaborators used advanced neuroimaging to examine cortical thickness and hippocampal volume in a diverse group of older adults. Their findings point to a troubling intersection of chronic disease and racial health disparities.
The study found that individuals with type 2 diabetes had significantly thinner cortices, especially in the temporal and parietal regions—areas critical for memory and cognition. Poor blood sugar control, measured by elevated hemoglobin A1c levels, appeared to drive these changes. “Since blood sugar levels can be managed with proper treatment and lifestyle interventions, our findings highlight the potential for protecting brain health through better diabetes management,” said Amaryllis A. Tsiknia, the study’s lead author.
Hispanic participants showed the strongest associations between diabetes and cortical thinning, even after accounting for socioeconomic status and other health conditions. In contrast, no significant effects were observed among non-Hispanic Black adults. “The disparities we observed by ethnic and racial group suggest that more work is needed to understand how exposures to various risk factors can work together in distinct ways across different people,” said Meredith N. Braskie, PhD.
As diabetes rates continue to rise, especially in minority populations, these findings underscore the urgent need for culturally tailored interventions to protect brain health.
See “Type 2 Diabetes Linked to Brain Thinning” (May 18, 2025)