Effects of Childhood and Adult Persistent Attention-Deficit/Hyperactivity Disorder on Risk of Motor Vehicle Crashes: Results From the Multimodal Treatment Study of Children With Attention-Deficit/Hyperactivity Disorder.

Objective: To determine motor vehicle crash (MVC) risk in adults with a history of childhood attention-deficit/hyperactivity disorder (ADHD) and persistent ADHD symptoms.

Method: Participants with (n = 441) and without (n = 239; local normative comparison group) childhood ADHD from the Multimodal Treatment of Attention-Deficit/Hyperactivity Disorder (MTA) Study were included. Participants provided self-reports on total number of MVCs they had been involved in and the time of licensure. Driving experience was estimated as the number of months since licensure. Total number of MVCs by adulthood was regressed on baseline ADHD status adjusting for sex, age at follow-up, driving experience, baseline oppositional defiant disorder/conduct disorder comorbidity, baseline household income level, adult oppositional defiant disorder/conduct disorder symptoms, adolescent and adult substance use, and adult antisocial personality disorder symptoms. We repeated the analysis using adult ADHD status (persistent versus desistant versus local normative comparison group) and symptom level as the predictor variables. Results are presented as incidence rate ratio (IRR) and CI.

Results: Childhood ADHD was associated with a higher number of MVCs (IRR = 1.45, CI = 1.15-1.82), and adult ADHD symptom persistence was associated with more MVCs than desistance (IRR = 1.46, CI = 1.14-1.86). ADHD desistance was not associated with a significantly increased risk for MVCs compared with the local normative comparison group (IRR = 1.24, CI = 0.96-1.61). Concurrent symptoms of inattention and hyperactivity/impulsivity predicted MVC risk.

Conclusion: Persistence of ADHD into adulthood is a stronger predictor of MVC risk than childhood-limited ADHD.

Clinical Trial Registration Information: Multimodal Treatment of Attention Deficit Hyperactivity Disorder (MTA) Study; https://clinicaltrials.gov; NCT00000388.