Attention-deficit/hyperactivity disorder persistence from childhood into young adult age: a 10-year longitudinal study

Introduction The aim of this study was to estimate ADHD persistence in a European clinical sample of children diagnosed with ADHD and followed prospectively for 10 years into young adulthood. Methods We assessed 85 children with ADHD at baseline (M-age = 11.6, SD = 2.1, 54% male) and re-assessed 59 at 10-year follow-up (M-age = 21.4, SD = 2.3, 54% male). ADHD symptoms at baseline were assessed with a semi-structured clinical interview (Kiddie-Schedule for Affective Disorders and Schizophrenia/Present and lifetime version) and parent rating scales (ADHD Rating Scale IV, Child Behavior Checklist). ADHD symptoms at 10-year follow-up were assessed with a semi-structured clinical interview (MINI-Plus) and self-report scales (ADHD Self-Report Scale version 1.1 screener, Adult Self Report). Functional impairment at 10-year follow-up was assessed with the Global Assessment of Functioning scale. Results At 10-year follow-up, 39% met ADHD symptom thresholds based on clinical evaluation using MINI-Plus or the ADHD Self-Report Scale version 1.1 screener or the Adult Self Report together with clinicians' rating of functional impairment. Conclusion ADHD persistence rates in this European clinical sample match previous estimates and indicate that a significant proportion of those diagnosed with ADHD as children still exhibit clinical levels of ADHD symptoms in adulthood.