Adults with ADHD at higher risk of many physical conditions, finds study Adults with ADHD are at higher risk of a wide range of physical conditions, including nervous system, respiratory, musculoskeletal, and metabolic diseases, according to a large register-based study from Karolinska Institutet in Sweden published in The Lancet Psychiatry. Identifying co-occurring physical diseases may have important implications for treating adults with ADHD and for benefiting the long-term health and quality of life of patients." Ebba Du Rietz, Study Lead Author and Postdoctoral Researcher, Department of Medical Epidemiology and Biostatistics, Karolinska Institute ADHD is a common neuropsychiatric disorder characterised by inattention, impulsiveness and hyperactivity, and commonly treated with stimulant therapy (methylphenidates or amphetamines).