Abstract
Attention deficit hyperactivity disorder (ADHD) is associated with mental health comorbidities, including anxiety. The purpose of this review is to describe evidence regarding the relationship between timing of ADHD medication initiation and long-term anxiety outcomes. Anxiety has a unique relationship to ADHD, as it tends to present earlier in individuals with ADHD compared to those without ADHD and can precede or co-occur with other disorders such as depression. Despite evidence that psychostimulant treatment can reduce short-term anxiety symptoms, the effects of ADHD medication on anxiety long-term are less clear, and the influence of age at medication initiation is unknown. This scoping review included a search of the databases MEDLINE (PubMed), Embase (Elsevier), and Web of Science (Clarivate). The search was conducted by a professional medical librarian in consultation with the author team and included keywords and subject headings representing ADHD, children, medication, and anxiety. Searches yielded a total of 3516 citations after removal of duplicates. Titles and abstracts were screened independently by two reviewers, and conflicts were resolved via discussion. Full-text articles were screened independently by a team of reviewers. Data extraction was completed independently by two reviewers. All screening and data extraction activities were piloted prior to completion. Two articles were selected for inclusion, and neither article found a relationship between age at ADHD medication initiation and long-term anxiety outcomes. Literature examining the relationship between age at ADHD medication initiation and long-term anxiety outcomes is scarce. Neither of the two articles included in this review revealed a significant relationship, however these results must be considered in light of major limitations. Future research is needed to discover the effects of age at ADHD medication initiation on long-term anxiety. This topic is of importance in development of clinical and policy interventions increasing access to early diagnosis and treatment of ADHD.