The socioeconomic burden of adult attention-deficit/hyperactivity disorder in Spain

Introduction: The symptoms of attention-deficit/hyperactivity disorder (ADHD) in adults highly interfere with function in multiple dimensions, increasing the economic burden associated with ADHD. The aim of this study was to explore the impact of ADHD in Spanish adults and estimate the associated economic burden within the healthcare, social, economic, and legal domains. Methods: An economic model was developed from a social perspective using a bottom-up approach, based on the scientific literature and a multidisciplinary expert group. Results: The cost incurred per diagnosed adult patient with ADHD included an annual cost of €15,652 and a one-time cost of €7,893 (3,035 M€ and 1,531 M€ for Spain, respectively). Regarding the annual cost, 50% was attributed to costs within the economic domain, of which 53% were work-absenteeism-related. Moreover, 28% was attributed to costs within the social domain, of which 74% were substance-abuse-related. Regarding the one-time cost, 52% was attributed to costs within the healthcare domain, of which approximately 50% were hospitalization-related costs. Moreover, 42% was attributed to costs within the legal domain, of which 62% were imprisonment-related costs. Conclusions: This is the first report on the socioeconomic burden of ADHD in Spanish adults, shedding light on the large burden that adult ADHD poses on the healthcare system and society at large, as symptoms have been shown to impact almost every aspect of life. This is particularly important for undiagnosed/untreated patients with ADHD in Spain, as appropriate treatments have shown positive results in these areas and may reduce its associated socioeconomic burden.