Teen drivers diagnosed with attention-deficit hyperactivity disorder (ADHD) are significantly more likely to crash, or engage in risky driving behaviours than their peers, a study has found. Researchers from Children's Hospital of Philadelphia (CHOP) in the US analysed detailed crash and traffic violation records for newly licensed drivers to conduct the first large-scale longitudinal study on this topic.
By highlighting the specific types of crashes and traffic violations, this study identifies risky driving behaviours that those with ADHD may be more likely to engage in, such as driving while intoxicated, not wearing a seat belt, and speeding.
Since these behaviours are amenable to change, the findings suggest that clinicians and families can work with this at-risk group of teens to practice safe driving behaviours and potentially reduce their crash risk.
"What this study suggests is that we have to go beyond current recommendations of medication and delaying the age of getting licensed to decrease crash risk for teens with ADHD," said Allison E Curry, lead author of the study published in the journal Pediatrics.
"Their higher rate of citations suggest that risky driving behaviours may account for why they crash more. More research is needed to objectively measure if and how these behaviours specifically contribute to crash risk," said Curry, from the University of Pennsylvania in the US.
Researchers reviewed the records of 14,936 adolescents who were patients at six CHOP primary care practices and had obtained an intermediate driver's license between January 2004 and December 2014.
The study team linked the adolescents' electronic health data with driver licensing records, traffic violations, and police-reported crash data. Within this group, the researchers identified 1,769 adolescents with childhood-diagnosed ADHD who obtained an intermediate driver's license during the study period, and compared their crash outcomes with those of the drivers without ADHD.
Although crash risk is elevated for all newly licensed drivers, the study team found it is 62 per cent higher for those with ADHD the first month after getting licensed, and 37 per cent higher during the first four years after licensure, regardless of their age when licensed.
Drivers with ADHD also experienced higher rates of specific crash types, including driving with passengers, at-fault-, single vehicle-, injury- and alcohol-related crashes, the last risk being 109 per cent higher than those without ADHD.
The rates of traffic and moving violations were also significantly higher among young drivers with ADHD as compared to those without ADHD. Among these drivers, nearly 37 per cent were issued a traffic violation and nearly 27 per cent a moving violation within their first year of driving, compared to 25 per cent and 18 per cent respectively among their peers without ADHD.
Drivers with ADHD had higher rates of alcohol or drug violations and moving violations -- including speeding, nonuse of seat belts, and electronic equipment use. Their rate was 3.5 times that of young drivers without ADHD in the first year of driving and 1.5 times that of young drivers without ADHD in the first four years of driving.