Identify Peripheral Biomarkers of Symptomatology, Neurocognitive Functions, and Medication Response in ADHD

Attention deficit hyperactivity disorder (ADHD), characterized by inattention, hyperactivity and impulsivity, is an early onset, highly heritable, clinically heterogeneous, long-term impairing disorder with tremendous impact on individuals, families, and societies. It affects 5-10% of school-aged children worldwide (7.5% in Taiwan) and 2-4% of adults. Although the efficacy of medications for ADHD is well demonstrated in clinical trials, substantial numbers of patients fail to remain on therapy, and there is tremendous variability in tolerability and treatment acceptance. It is of great interest to identify biomarkers relating to medication response in ADHD. However, the procedure for obtaining central markers such as PET scan is invasive and expensive. Previous studies have found that mRNA expression of neurochemical markers in circulating blood can reflect the neurochemical levels in the brain. Further studies to identify peripheral biomarkers related to medication response in ADHD are warranted.