Investigating Brain and Biological Development in Children and Their Relationship with Physical, Mental, and Academic Outcomes
Brain age and biological age, estimated using machine learning models with brain imaging and biological features, have emerged as promising biomarkers for predicting a broad range of health outcomes in adults. However, very few studies have examined the counterpart of brain age and biological age in children, that is Brain Development Index (BRDI) and Biological Development Index (BIDI). Existing studies on BRDI and BIDI are largely cross-sectional and do not provide adequate information on their temporal trajectory and predictive power for future health outcomes in children. Additionally, the interconnectedness of BRDI and BIDI across multiple health domains, especially child-specific developmental outcomes, remains underexplored. Our study utilized brain imaging features and blood-based biomarkers from the Adolescent Brain and Child Development (ABCD) study to assess the trajectory of BRDI and BIDI over multiple time points. We examined their relationships with physical, mental, and academic health outcomes. Lastly, we utilize Bayesian network analysis to examine the relationship between the two indexes and their subcomponents. We found that delayed BRDI and BIDI were significantly associated with adverse future health outcomes across several domains. In addition, Bayesian network analysis revealed BRDI and BIDI subcomponents influence one another across different organ systems. Additionally, males exhibited more advanced BRDI, while females showed more advanced BIDI, revealing important sex differences in adolescent development. This research provides the first comprehensive analysis of BRDI and BIDI trajectories, revealing their predictive power for future health outcomes and offering new insights into the interconnected development of brain and biological systems in children.