Author(s)

Shuhao Li, Ding Wang, Yingjie Zhu

Corresponding Author

Shuhao Li

ABSTRACT

Attention-deficit hyperactivity disorder (ADHD) is a major neurodevelopmental health concern characterized by impairing patterns of inattention, impulsivity, and hyperactivity. As the causes of ADHD are multifaceted, this paper explores the etiology of ADHD and its induced factors through assessments of familial aggression and environmental impacts. Family studies and twin studies are involved in explaining the findings. Besides, this paper also aims to evaluate the co-occurrence risk of ADHD with other psychiatric disorders and physical disorders by noticing that comorbidity among this tripartite relationship is significant. Psychiatric comorbidities in ADHD are discussed in terms of mood disorders and substance use disorders; on the other hand, physical diseases mainly cover chronic inflammatory diseases and allergic diseases. Based on the evidence, ADHD is a genetic-related disorder with few shared environmental influences, which means that familial risk increases with a decreasing distance of biological relationships. Also, ADHD has high comorbidities with psychiatric disorders, including bipolar disorder, major depression, anxiety, and substance use disorder. Regarding physical diseases, cystic fibrosis, asthma, allergic rhinitis, and atopic dermatitis are found to coexist with ADHD. From clinical perspectives, our work on familial risk evaluation could facilitate the identification of ADHD in the family units to initiate medical care in the early stage. The co-occurrence feature may provide a detailed overview for exploring more possibilities to establish a more precise and complete diagnostic system.

KEYWORDS

Attention-deficit-hyperactivity disorder, Etiology, Family Study, Twin Study, Comorbid disorder