Attention deficit hyperactivity disorder is not only affecting children but also adults and their work, according to new research led by Dr. Ron de Graaf of the Netherlands Institute of Mental Health and Addiction.

ADHD is one of the most well-recognized childhood developmental problems. The condition is characterized by inattention, hyperactivity and impulsiveness. It is now known that these symptoms continue into adulthood for about 60 percent of children with ADHD.

Adults with ADHD may have difficulty following directions, remembering information, concentrating, organizing tasks or completing work within time limits. If these difficulties are not managed appropriately, they can cause associated behavioral, emotional, social, vocational and academic problems.

Now, the new study found that the lack of ability to concentrate, which characterizes ADHD, costs the average adult sufferer 22.1 days of “role performance,” per year, including 8.7 extra days of absence.

Knowing how much work is lost, the researchers recommend employers consider screening staff for ADHD and provide treatment for those affected. This variant would be more cost-effective for their businesses. A similar approach with depressed employees reportedly helped prevent $4,000 in lost productivity for each $1,000 spent.

The study involved more than 7,000 employed and self-employed workers aged 18-44 years in 10 countries who were screened for ADHD as part of the World health Organization’s World Mental Health Survey Initiative. The researchers found that 3.5 percent of workers had ADHD, the condition being more prevalent in men than in women. This translates in losing about 28.3 days of performance.

According to findings of another study published last month in the American Journal of Psychiatry by a team of researchers led by Dr. Ronald C. Kessler of Harvard University, also a co-author of the new report, major mental disorders cost the U.S. at least $193 billion annually in lost earnings alone.

The findings of the study were published in Tuesday’s online edition of the journal Occupational and Environmental Medicine.