Childhood ADHD traits and young-adult labor market marginalization: a co-twin control study

Abstract Background Attention-deficit hyperactivity disorder (ADHD) is linked to adverse labor market outcomes, yet most studies lack consideration of potential confounding by familial factors (i.e., genetics and shared early environment). We aimed to examine associations of childhood ADHD traits with long-term unemployment (LTU), long-term sickness absence (LTSA), and disability pension (DP), accounting for familial factors. Methods Prospective cohort study of Swedish twins, born 1992-2002, whose parents were surveyed when twins were aged 9 years (n = 20896, 51% males). Twins were screened for neurodevelopmental traits using the Autism-Tics, ADHD, and other Comorbidities inventory. Registry-based outcomes included LTU (≥180 days), SA (≥60 days), and DP (any) from 2008 to 2021. Cox regression analyses were run to obtain Hazard Ratios (HR) both for the full cohort (n = 1201 with ADHD; n = 19695 with no ADHD) and for twin pairs discordant for ADHD (n = 549 pairs). Analyses were adjusted for sex and autistic traits. Results During follow-up, LTU was experienced by 14.8%, LTSA by 4.7%, and DP by 4.2% of individuals. In the full cohort, ADHD was significantly associated with LTU (HR = 2.14, 95% CI = 1.88-2.44), LTSA (HR = 1.71, 95% CI = 1.32-2.22), and DP (HR = 4.70, 95% CI = 3.82-5.79). Among discordant twin pairs, ADHD remained significantly associated with LTU (HR = 1.65, 95% CI = 1.23-2.22), LTSA (HR = 2.13, 95% CI = 1.16-3.94), and DP (HR = 1.95, 95% CI = 1.28-2.96). Conclusions Childhood ADHD traits were strongly associated with elevated risks of adverse labor market outcomes. While the magnitude of some associations was reduced after control for familial factors, notably for DP, the risk estimate for LTSA was higher. This suggests familial factors may bear relevance to some but not all outcomes; individual-specific environmental factors are also important to consider. Targeted interventions are much needed to support afflicted youths in transitioning to employment and to mitigate labor market marginalization. Key messages • The study calls for a multifaceted approach to address the longitudinal links between early ADHD traits and labor market outcomes to improve transitions into paid work for affected individuals. • Developing early prevention targets that address both the direct effects of ADHD and the influence of familial factors on labor market marginalization seem important from a public health perspective.