WASHINGTON (CBS DC) — A new study finds there has been a 70 percent increase in the number of ADHD diagnoses among African-American children in recent years.

In a recent study conducted by Getahun and published in JAMA Pediatrics, African-American children have been diagnosed with the hyperactivity disorder at much greater rates than that of other ethnic and racial groups. The Getahun study was conducted using medical records from almost 850,000 children ranging in age from 5 to 11 years old.

ADHD is defined by the Mayo Clinic as, “a chronic condition that affects millions of children and often persists into adulthood. ADHD includes some combination of problems, such as difficulty sustaining attention, hyperactivity and impulsive behavior. Children with ADHD also may struggle with low self-esteem, troubled relationships and poor performance in school.”

In the same study, Hispanic youth showed a diagnosis increase of 60 percent, and a 30 percent increase among white children.

There was also a gender gap: African-American girls saw the largest increase, recording a 90 percent rise in ADHD diagnoses. ADHD has traditionally been more prevalent among boys in comparison to girls, 11 percent compared to 5 percent. However, the Getahun study shows that this gender gap is closing for African-American children.

Dr. Richard Gallagher of the Institute for Attention Deficit Hyperactivity and Behavior Disorders at NYU Child Study Center cautioned parents not to be alarmed that there has been a huge jump in the use of the diagnosis of ADHD due to previous studies that have shown minorities have long been under-diagnosed for the hyperactivity disorder.

The study states that, “Children with untreated ADHD are more likely to have problems in school because they are easily distracted and have difficulty learning. Untreated ADHD also impacts social relationships because children with ADHD often don’t get along well with others. An additional consequence of untreated ADHD is an increase in physical injuries due to hyperactivity and disruptive outbursts.”

The study warns that many youth with untreated ADHD continue to have symptoms as adults and are less likely to manage the responsibility required of maintaining jobs and relationships.