Metabolomic Insights into Attention Deficit Hyperactivity Disorder: A Scoping Review.

Attention deficit hyperactivity disorder (ADHD) is the most common neurodevelopmental condition, and symptoms persist into adulthood. Its etiology, though recognized as multifactorial, is still under discussion. Metabolomics helps us to identify pathways associated with functional and structural changes that may be related to symptomatology. This study aimed to characterize potentially altered metabolic pathways and associated biochemical reactions in ADHD. A scoping review of experimental research was conducted using PubMed, Web of Science, and Scopus using PRISMA ScR. Fifty-five studies were eligible for data extraction, of which fifteen met the criteria for inclusion in the review. Subsequently, the identified metabolites were analyzed in the context of the literature to recognize possible discordant pathways in the disorder. Two groups of relevant neuromodulators of ADHD were found: precursors of monoamines and polyunsaturated fatty acids. The literature was reviewed to discover potential implicated pathways and new metabolites of interest. The study of ADHD biomarkers should focus on measuring precursor, intermediate, and final metabolites of polyunsaturated fatty acids and monoamines in panels or through untargeted analysis to improve the understanding of the pathology and individualization of treatments.