Abstract: Described herein are methods and composition for diagnosing and evaluating the treatment of depression using one or more biomarker metabolites for the diagnosis and monitoring treatment efficacy. In one aspect, the biomarker metabolites can be used to screen subjects for the likelihood of developing depression, the diagnosis thereof, monitoring the efficacy of treatment, and evaluating a subject's propensity for responding to treatment.

Abstract: Embodiments of the present disclosure relate generally to the analysis of broad metabolic changes associated with neurological disorders. In particular, the present disclosure provides materials and methods relating to the use of metabolomics as a biochemical approach to identify peripheral metabolic changes and corresponding metabolic biomarkers of neurological disorders. Embodiments of the present disclosure include the use of bile acids and their derivatives as metabolic biomarkers to aid in the determination of whether a subject suffers from, or is at risk of developing, a neurological disorder, such as Alzheimer's Disease (AD).