Adults with attention deficit hyperactivity disorder (ADHD) have a significant risk of being involved in serious transport accidents, such as car or motorcycle accidents, compared to individuals without ADHD.
A new Swedish study discovered that up to half of the transport accidents involving men with ADHD could be avoided if the men were taking medication for their condition.
The study is published in the journal JAMA Psychiatry.
Investigators studied 17,000 individuals with ADHD over a period of four years (2006-2009) using various population health’ registers.
They then analyzed the risk of transport accidents for individuals diagnosed with ADHD and how ADHD medication influence this risk.
In line with previous research in this area, the results from the current study demonstrates that individuals with ADHD have a 45 percent increased risk of being involved in a serious transport accident, as compared to individuals without ADHD.
“Even though many people with ADHD are doing well, our results indicate that the disorder may have very serious consequences,” said Henrik Larsson, Ph.D., associate professor at the Department of Medical Epidemiology and Biostatistics.
The study also demonstrates in several different ways that the risk of transport accidents in adult men with ADHD significantly reduces if their condition is treated with medication.
In the study, researchers discovered the incidence of transport accidents was lower among men with ADHD who received medication than among men with ADHD who did not.
When the men were compared to themselves, i.e. during periods with and without ADHD medication, the researchers were able to establish that pharmaceutical treatment involved a significantly lower risk of transport accidents; during the periods of ADHD medication the risk was 58 percent lower.
Comparing the individuals to themselves is one of the study’s strengths as it demonstrates that the connection between medication and decreased accident risk is probably not due to differences between individuals.
Further statistical calculations showed that 41 percent of the transport accidents involving men with ADHD could have been avoided if they had received medication for the entire follow-up period.
The study, however, does not explain the specific mechanisms behind the effect of ADHD medication on accident risk.
Nevertheless, researchers believe the results may be explained by ADHD medications having an effect on the core symptoms of ADHD such as impulsiveness and distractibility, which in turn reduces the risk of getting into trouble on the road.
“Despite having shown that medication for ADHD very likely reduces men’s risk of transport accidents, we could not establish a similar reduction in women’s accident risk,” Larsson said. “We need further data to be able to comment about the effect on women with statistical certainty. It is also important to point out that most pharmaceutical treatments carry a risk of side effects.”
“The risks must be weighed against the benefits for every individual prescription, taking into account the individual patient’s situation.”
About five percent of all school children and half as many adults suffer from ADHD, which is characterized by lack of attention, concentration difficulties and impulsiveness.
Research has shown that ADHD is a relatively stable disorder and many of those who have been diagnosed with ADHD as children also meet the diagnostic criteria as adults.
People with ADHD can be treated with medications such as central nervous system stimulants that affects the brain and thereby improve attention and impulse control.
Source: Karolinska Institutet