Estimations of economic burden associated with ADHD in the current literature are focused on a few countries only, and little is known about the global impact. The aim of this review was to summarise the current economic burden of ADHD on the global scale.
A comprehensive search was conducted from inception of databases to 15 December 2020, in EconLit, EMBASE, PubMed, Cochrane Review (DARE), ERIC and PsycINFO.* All identified studies were evaluated based on whether they were an original research article and reported the economic burden of ADHD.† Selection criteria were not limited to any language, therefore minimising language bias. A meta-analysis was not conducted due to substantial methodological and statistical heterogeneity. Identified studies were classified according to direct costs (direct medical and non-direct medical), indirect costs, education system costs and justice system costs. All costs are shown in US dollars.
Out of the initial 17,639 articles that were identified using the search strategy, a total of 44 relevant articles were included in the review. All studies were conducted in high-income countries and were mostly limited to North America and Europe (there were 25 studies in the USA, 15 in Europe, and two each in Asia and Australia). One of the European studies provided data from Canada, Denmark, France, the Netherlands and the UK.
Annual estimates based on total costs
The estimated per-person total annual economic burden in North America ranged from $1028.06–18,158.09 for individuals with ADHD (including children, adolescents and adults) and from $149.01–4249.00 for family members of individuals with ADHD. In Europe, the estimated per-person total annual economic burden ranged from $831.83–20,538.95 for individuals with ADHD (including children, adolescents and adults) and $2670.43–4119.75 for family members of individuals with ADHD. Only children and adolescents with ADHD data were included in studies from Asia and Australia, and only direct costs were measured to estimate the economic burden of ADHD. Per-person direct costs ranged from $596.27–2626.08 for children with ADHD. The estimated annual national total economic burden for individuals with ADHD (including children, adolescents and adults) in North America ranged from $2.27 billion–20.27 billion. The estimated cost as a percentage of gross domestic product (GDP) was 0.1% for the USA and 0.13% for Canada. In Europe, the estimated total annual national costs of ADHD (data only available for adults) ranged from $356.14 million–416.80 million. As a percentage of GDP, estimated costs were 0.1% for Denmark, 0.15% for France, 0.12% for the Netherlands and 0.14% for the UK. Reported estimated costs of ADHD in children and adolescents were $53.16 million for Asia and $27.98 million for Australia.
Annual estimates based on total excess costs
The excess total costs related to ADHD in North America ranged from $244.15–15,828.00 for children, adolescents and adults with ADHD and from $60.59–4005.10 for family members of individuals with ADHD. For Europe, the excess total cost related to ADHD in children, adolescents and adults with ADHD ranged from $550.28–18,751.63, and was $3906.21 for family members of individuals with ADHD, as reported in one study. For children and adolescents in Asia, only data for excess direct costs related to ADHD were available and were reported as $245.52. Additionally, the excess total costs for children, adolescents and adults with ADHD in Australia ranged from $1603.89–8173.00. The estimated annual total national economic burden attributable to ADHD in North America ranged from $966 million–141.33 billion for children, adolescents and adults with ADHD, and the estimated costs as a percentage of GDP were 0.09% for the USA and 0.12% for Canada. For Europe, the excess total costs for individuals with ADHD ranged from $325.14 million–3767.62 million. The estimated cost as a percentage of GDP was 0.09% for Denmark, 0.14% for France, 0.11% for the Netherlands and 0.13% for the UK. In Australia, one study reported excess total costs of $17.09 million for children and adolescents with ADHD, and a second reported excess costs of $6.66 billion for children, adolescents and adults with ADHD. No data for excess total costs related to ADHD were available for Asia.
A limitation to this systematic review was that the search strategy aimed to capture all probable causes of economic burden of ADHD; however, the term ‘productivity’ was omitted from the search due to initial searches providing a substantial number of research articles that limited the feasibility of the process. The authors believed that the inclusion of terms related to ‘burden’ and ‘costs’ was sufficient to extract all targeted articles. Additionally, there could have been overlap between the four domains: direct, indirect, educational and justice system costs. Finally, the heterogeneity of the data across different parameters did not allow for a pooled analysis to be performed.
To conclude, the authors suggested that this systematic review reveals that there is a substantial societal economic burden imposed by ADHD. Also, the authors suggested that to improve the standardisation of cost-of-illness studies, a guideline on the conduct and reporting of economic burden studies could be developed.
Read more about the global economic burden of ADHD here
*Search strategy for relevant literature was: (“cost of illness” OR cost* OR burden OR economic* OR expenditure”) AND (“Attention Deficit Disorder with Hyperactivity” OR “ADHD”)
†Exclusion criteria included: animal studies, case-series, case studies, economic evaluation of specific ADHD treatments, editorials, reviews and studies that combined costs across different cost domains (aggregate costs)
Chhibber A, Watanabe AH, Chaisai C, et al. Global economic burden of attention‑deficit/hyperactivity disorder: a systematic review. Pharmacoeconomics 2021; 39: 399-420.