As many as twenty percent of children in the United States are living with mental health disorders and the number of diagnoses has been steadily rising for more than a decade, according to a new report from the Centers for Disease Control and Prevention (CDC)

The study titled "Children's Mental Health Surveillance" paints a bleak picture of millions of American adolescents struggling with mental disorders and found that less than half of those children are receiving the treatment they need. In the agency's first-ever study of mental disorders among children aged 3 to 17, researchers found childhood mental illnesses affect between 13 percent and 20 percent, or about 1 in 5 children and cost $247 billion per year in medical bills, special education and juvenile justice.

According to the report, some examples of childhood mental disorders are:

  •  Attention-deficit/hyperactivity disorder (ADHD)
  •  Behavior disorders
  •  Mood and anxiety disorders
  •  Autism spectrum disorders
  •  Substance use disorders
  •  Tourette Syndrome

"This is a deliberate effort by CDC to show mental health is a health issue. As with any health concern, the more attention we give to it, the better. It's parents becoming aware of the facts and talking to a healthcare provider about how their child is learning, behaving, and playing with other kids," Dr. Ruth Perou, the lead author of the study, told Reuters in an interview.

"What's concerning is the number of families affected by these issues. But we can do something about this. Mental health problems are diagnosable, treatable and people can recover and lead full healthy lives," Perou added.

Perou says her team of researchers also found that attention deficit or hyperactivity disorder (ADHD), autism spectrum disorders, and bipolar disorders in American children and adolescents have increased over the last two decades, along with drug use. Substance-abuse disorders, however, have not increased among children, teenagers, and adolescents.

ADHD is the most prevalent current diagnosis in American children ages 3 to 17.

The report highlights just how much work must be done in diagnosing and managing widespread mental disorders in children and adolescents that often remain untreated into adulthood.

The study used data collected between 1994 and 2011 that showed the number of kids with mental disorders is growing. The study stopped short of concluding why, but suggested improvements in diagnoses as one possible explanation.

"This report is a reflection of what's happening in the nation as a whole," Perou said. "We're finally opening a dialogue on mental health."