Abnormalities in Brain Linked to Comorbid ADHD in Bipolar Disorder

Abnormalities in brain structure which are detected through MRI or magnetic resonance imaging in patients who have Bipolar Disorder may have been erroneously associated to the disorder. The similarities of the symptoms of ADHD and Bipolar Disorder and their frequent coexistence make it difficult to distinguish one from the other. Obtaining an accurate diagnosis remains to be a challenge.

According to new research, abnormalities may actually be attributed to the Bipolar Disorder patient who also has symptoms of ADHD. ADHD and Bipolar Disorder has a comorbidity prevalence of 5 to 20 percent. These two frequently co-exist but often overlooked when looking at MRI scans. For the new study, the University of California at Los Angeles researchers set out to find out how Bipolar Disorder and ADHD separately contributed to abnormalities in the brain found during MRI.

The study recruited 85 participants 17 of which had Bipolar Disorder and 19 had ADHD only. 18 participants had both ADHD and Bipolar Disorder and 31 showed no indication of any mental disorder. The Bipolar Disorder participants were not taking lithium and were not in depressive state.

MRI was used by the researchers to measure the participants cortical thickness. Through an analysis of the frontal part of the cingulate cortex and the anterior part of the brain’s frontal lobes, results showed the participants who have Bipolar Disorder lessened cortical thickness with and without co-existing ADHD. On the other hand, the effect of Bipolar Disorder on the cortical thickness was not the same in patients with ADHD and without ADHD in the right orbitofrontal cortex and left subgenual cingulated.

Through the MRI researchers observed that cortical thinning in the right orbitofrontal cortex was linked with Bipolar Disorder, only if the patient has no ADHD diagnosis. The presence of ADHD, in the left subgenual cingulated removed the thinning of the brain’s cortex linked with Bipolar Disorder.