The brain sometimes ages faster than the body, with various diseases exerting a distinct influence on this process. A large-scale study by researchers at Nanjing University of Aeronautics and Astronautics has made it possible to track exactly how this occurs.
The Chinese scientific team compared structural MRI data from approximately 48,600 individuals. Of these, 45,900 formed a control group, while 2,698 were patients diagnosed with a range of conditions. These included Alzheimer’s disease, bipolar disorder, ADHD, alcohol and tobacco dependence, as well as several other neurological, psychiatric, and psychological disorders.
To assess the rate of aging, the team used a metric known as predictive age difference (PAD)—the gap between chronological age and the “brain age” estimated from scans. A positive PAD value indicates that the brain is prone to premature aging.
The most pronounced effect was observed in neurodegenerative conditions, such as Alzheimer’s disease and mild cognitive impairment. Addictions and certain mental disorders were linked to a moderate increase in PAD. However, individuals with ADHD and autism spectrum disorders showed no noticeable differences from the control group.
Across all the diseases studied, accelerated aging was typically detected in the prefrontal cortex, which is responsible for cognitive control. A more detailed analysis revealed that psychiatric conditions primarily left their mark on activity in the frontal and temporal lobes, dementia was correlated with changes in the frontal and occipital cortex, and addictions were reflected in alterations within the default mode network, the putamen, and the thalamus.
The authors hope that these findings will serve as a foundation for identifying biomarkers and gaining a deeper understanding of the mechanisms that drive accelerated brain aging in various pathologies.
About the Author
