Conditions like oppositional defiant disorder and conduct disorder often occur with ADHD

Attention-deficit/hyperactivity disorder (ADHD) occurs in about 3 to 5 percent of children and teenagers, and many researchers now believe that ADHD occurs in combination with other psychiatric conditions in a majority of affected youth.

A 2011 study of over 5,000 children and teenagers with ADHD aged six to 17 years revealed that about two-thirds of them had at least one comorbid (co-occurring) condition, and 18 percent of them had three or more comorbid conditions.

Some of the other conditions that children and teens with ADHD often have include depression, oppositional defiant disorder, conduct disorder, bipolar disorder, anxiety and substance abuse disorder. Teenagers with more severe symptoms of ADHD are likely to develop comorbid conditions.

Researchers aren't certain what causes ADHD or the conditions that are often associated with it. Some experts believe that a combination of genetic factors and brain irregularities may contribute to the connection.

ADHD and Comorbid Conditions: One Thing Follows Another

A 2010 study found that people with depression or bipolar disorder and ADHD showed symptoms of their depression or bipolar disorder earlier than people without ADHD. The study also reported that people with those comorbidities had higher rates of other conditions (like agoraphobia and anti-social personality disorder), and their comorbidities were likely to have a serious impact on their quality of life and employment status.

Comorbid conditions have their own sets of symptoms, which may or may not overlap the symptoms of ADHD.

If you're concerned about a teenager with ADHD who may have a comorbid condition, it's important to work with a qualified physician or ADHD specialist to make an accurate diagnosis. Diagnosing comorbid conditions usually involves a combination of physical examination, behavioral observation and standardized tests.

Treatment, too, must be carefully considered, when comorbid conditions are involved. Treatments may involve behavioral modification, medication, and/or psychological counseling.


American Academy of Child & Adolescent Psychiatry

Centers for Disease Control and Prevention

"Attention-Deficit/Hyperactivity Disorder in Adults With Bipolar Disorder or Major Depressive Disorder: Results From the International Mood Disorders Collaborative Project." Roger S. McIntyre, et al. Primary Care Companion Journal of Clinical Psychiatry. 2010; 12(3): PCC.09m00861.

National Institute of Mental Health

"Patterns of Comorbidity, Functioning, and Service Use for US Children With ADHD, 2007." Kandyce Larson, et al. Pediatrics. Published online February 7, 2011.

Publication Review By: the Editorial Staff at

Published: 10 Feb 2011

Last Modified: 27 Aug 2015