Global Economic Burden of Attention-Deficit/Hyperactivity Disorder: A Systematic Review

Background Attention-deficit/hyperactivity disorder (ADHD) is one of the most common mental disorders affecting children and adults. Previous systematic reviews have provided estimates of ADHD-associated costs but were limited to the USA and Europe. Objectives This study aimed to systematically summarise all global evidence on the economic burden of ADHD. Methods A systematic search for published studies on costs of ADHD was conducted in EconLit, EMBASE, PubMed, ERIC, and PsycINFO. Additional literature was identified by searching the reference lists of eligible studies. The quality of the studies was assessed using the Larg and Moss checklist. Results This review included 44 studies. All studies were conducted in high-income countries and were limited to North America and Europe except for four studies: two in Asia and two in Australia. Most studies were retrospective and undertook a prevalence-based study design. Analysis revealed a substantial economic impact associated with ADHD. Estimates based on total costs ranged from $US831.38 to 20,538 for per person estimates and from $US356 million to 20.27 billion for national estimates. Estimates based on marginal costs ranged from $US244.15 to 18,751.00 for per person estimates and from $US12.18 million to 141.33 billion for national estimates. Studies that calculated economic burden across multiple domains of direct, indirect, and education and justice system costs for both children and adults with ADHD reported higher costs and translated gross domestic product than did studies that captured only a single domain or age group. Conclusions Despite the wide variation in methodologies in studies reviewed, the literature suggests that ADHD imposes a substantial economic burden on society. There is a dire need for cost-of-illness research in low- and middle-income countries to better inform the treatment and management of ADHD in these countries. In addition, guidelines on the conduct and reporting of economic burden studies are needed as they may improve standardisation of cost-of-illness studies.