Background: Attention deficit hyperactivity disorder (ADHD), characterized by inattention, hyperactivity and impulsivity, is an early onset, common (5-10% worldwide; 7.5% in Taiwan), clinically heterogeneous, impairing disorder. Despite the abundance of research on ADHD, the vast majority of samples have been limited to Caucasians; there is limited information about the expressions, patterns, correlates, and outcomes for ADHD in the Taiwanese population.
- to investigate the neuropsychological functioning, and psychiatric, academic, and social outcomes of ADHD at adolescence;
- to examine the psychopathology and neuropsychological functioning among parents and siblings of ADHD probands;
- to determine the components of ADHD and neuropsychological functioning with the greatest familial recurrence risks; and
- to validate the classification of ADHD and comorbid subtypes of ADHD using psychosocial, familial, neuropsychological and longitudinal data.
Subjects and Methods: This 5-year proposal consists of two parts: (1) a 3 year-retrospective cohort study and family study design; and (2) a 2 year-prospective cohort study design. Several Chinese version of rating scales will be prepared in the first 6 months. The sample will consist of probands with (n=180) and without (n=90) ADHD, ages 11-16, recruited from the Children's Mental Health Center, NTUH and an epidemiological study. The ADHD diagnosis has been made 3-6 years ago prior to recruitment. Probands and their parents will be assessed using the following measures (n=810) in the first 3 years. Only probands will be reassessed in the last 2 years. The measures will include a psychiatric interview using K-SADS-E and self-reports covering the individual and familial/environmental domains; and neuropsychological tests (WISC-III, CPT, WCST, CANTAB). The informants include probands and their parents and teachers.
Long-term Objectives: The long-term objectives are to identify the endophenotypes that are close to the biological expression of genes underlying ADHD, to determine the familial aggregation and its specificity regarding the components of ADHD, and neuropsychological deficit, and to identify the impact of ADHD on academic, psychiatric, family, and social outcomes; and to identify a cohort of families with ADHD for future neuroimaging, neurophysiological, and molecular genetic studies.