Teenage male drivers with ADHD are more likely to be involved in a car crash

15/11/2010

Teenage male drivers are twice as likely as the average population to be involved in a serious crash. But new research conducted at the Institute for Clinical Evaluative Sciences (ICES) has found a further one-third increase in crash risk among teenage boys diagnosed with attention deficit hyperactivity disorder (ADHD) and other disruptive behaviour disorders.

“Our study found the magnitude of ADHD is similar to the increased risk with epilepsy. The findings call attention to a widespread, preventable, and costly cause of death and disability. Perhaps ADHD should be considered in assessments of fitness to drive,” says principal investigator and ICES senior scientist Dr. Donald Redelmeier.

The study looked at 3,421 males between the ages of 16 and 19 who were involved in serious road trauma between April 1, 2002 and March 31, 2009.

The highlights include:

Most crashes are caused by driver error and can be prevented
Distractions contribute to at least one-third of all serious road crashes
Many sources of distraction are recognized (e.g. mobile phones)
ADHD is associated with about a 37 per cent relative increase in risk
The increased risk also extends to teenagers involved as pedestrians
The increased risk was evident years before the crash occurred

“Many drivers overestimate their skills and underestimate their risks. These findings show that the increased risk might be mitigated with better awareness and treatment of ADHD. Recommendations include avoiding excess speed, restricting alcohol, and minimizing other distractions. Other good advice includes using seat belts, keeping distance from other vehicles and obeying medical advice,” says Dr. Redelmeier.

Author affiliations: ICES (D. A. Redelmeier, W. K. Chan, H. Lu); Dept. of Medicine, U of T (D. A. Redelmeier, W. K. Chan); Clinical Epidemiology Program, Sunnybrook Health Sciences Centre (D. A. Redelmeier); Patient Safety Service, Sunnybrook Research Institute (D. A. Redelmeier).

The study “Road trauma in teenage male youth with childhood disruptive behavior disorders: a population based analysis” is in the November 16, 2010 issue of PLoS Medicine.

ICES is an independent, non-profit organization that uses population-based health information to produce knowledge on a broad range of healthcare issues. Our unbiased evidence provides measures of health system performance, a clearer understanding of the shifting healthcare needs of Ontarians, and a stimulus for discussion of practical solutions to optimize scarce resources. ICES knowledge is highly regarded in Canada and abroad, and is widely used by government, hospitals, planners, and practitioners to make decisions about care delivery and to develop policy.