Melissa DelBello, M.D., is Assistant Professor of Psychiatry and Pediatrics at the University of Cincinnati College of Medicine, and Director of the Child and Adolescent Psychiatry Division, Psychotic and Bipolar Disorder Research Program. She also has a clinical practice at the Children’s Hospital Medical Center in Cincinnati, where she co-directs the Mood Disorders Program. She has received over a dozen awards and honors for her work, including two Resident Research awards from her department and the Presidential Scholar Award from the American Academy of Child and Adolescent Psychiatry.

The Balanced Mind Foundation: Dr. DelBello, In your work you’ve studied the brain anatomy of children who are at risk for bipolar disorder. What are the objectives of your neuroimaging research on these children?

Dr. DelBello: One of our overall goals is to understand what differentiates children who are at risk for bipolar disorder from other children. The ultimate goal is to identify neurobiological markers (physical differences in the chemistry and structure of the brain) for bipolar disorder so that we can more effectively treat those who are at risk for developing it.

The Balanced Mind Foundation: How do you define this “at risk” population?

Dr. DelBello: We define at-risk children as those who have at least one parent with bipolar I disorder.

The Balanced Mind Foundation: What have you found with respect to the brain anatomy of these children? Were there differences?

Dr. DelBello: We found enlarged prefrontal lobes and neurochemical differences in the prefrontal lobes and cerebellum of children at risk for bipolar disorder compared with children without a family history of bipolar disorder. Not all of the at-risk children exhibit these differences, though. The prefrontal part of the brain is the control and command center. When the prefrontal lobes exert poor control over other brain centers, such as the amygdala--which is involved in regulating emotion--you may end up with mood instability and attention problems similar to those we see in bipolar disorder. Not all of our at-risk children showed clear symptoms of bipolar disorder, and not all of them will, in fact, develop it, yet these neurobiological differences are already evident.

The Balanced Mind Foundation: Do these structural abnormalities change over time?

Dr. DelBello: We don’t know for sure, and we are currently investigating whether the symptoms and brain differences change over time. However, we did find in another study of adult bipolar patients that a certain part of the cerebellum was smaller in patients who had had multiple manic episodes as compared to patients who had had, at most, only one manic episode in their lives. This evidence suggests that perhaps there is some kind of neurodegeneration, or progressive cell death, in bipolar patients who have had multiple episodes.

The Balanced Mind Foundation: Can brain scans of any sort be used to diagnose bipolar disorder?

Dr. DelBello: No, absolutely not. This is always the first thing parents want to know! Since we find differences between groups of patients with bipolar disorder or at risk for bipolar disorder and healthy volunteers it does not necessarily mean that each individual patient has these changes. Imaging is not a reliable diagnostic tool. Many parents tell me their children have been diagnosed with bipolar disorder using an MRI. Parents should know that at this point neither EEGs nor MRIs nor any other test, for that matter can definitively diagnose bipolar disorder or indicate which types of medication might work best to manage it. We gathered our data using MRI, morphometric (volume, shape and size comparison) analysis and magnetic resonance spectroscopy to examine and measure neurochemistry and brain anatomy. These technologies allow us to assess the total volume and analyze the chemical make-up of brain structures, but at this point, in patients with bipolar disorder they are reliable tools for research purposes only.

The Balanced Mind Foundation: Your work has also looked at the cognitive functioning in children at risk for bipolar disorder. Is there a typical set of neuropsychological deficits in children who are at risk for the disorder?

Dr. DelBello: We administered a thorough battery of tests that examined attention, memory, and executive functioning. Our findings on the neuropsychological studies tie right in with our MRI findings. Kids at risk for bipolar disorder had more anxiety, more mood disorders, and more ADHD. Specifically, these children seem to have abnormalities with executive function. This is a hard concept to define, but is regarded as the ability to plan, problem-solve and reason. It means they have trouble putting complex things together, and in getting organized in everyday life with things like doing homework, getting dressed for school, planning ahead, and following a teacher’s instructions. The prefrontal cortex of the brain, where the MRIs detected structural abnormalities, is believed to be largely responsible for executive function.

Also, the at-risk kids have coordination and balance problems. We asked them to balance on one foot for 30 seconds and to walk a straight line for ten steps, like a drunk driver, with their eyes open and then closed. Children at risk for bipolar disorder can’t do it either way. Children in our control group could do this with their eyes open, but not with their eyes closed. That ability to maintain balance is controlled by the cerebellum, which has been implicated in studies of adults with bipolar disorder. The pathophysiology of bipolar disorder appears to involve the prefrontal-subcortical-cerebellar circuit.

The Balanced Mind Foundation: Does this mean that every child at risk for bipolar disorder should have a neuropsychological evaluation?

Dr. DelBello: No, it doesn’t. If children are not having any functional difficulty, there is no reason to be tested. However, these differences are sometimes subtle. In our data, some kids did not have any symptoms of a mood disorder did have neuropsychological deficits. Certainly, children who show signs of functional impairment such as difficulty in school, should have a full battery of tests: academic achievement, IQ, learning disabilities, attention, memory all these areas of cognition should be assessed to identify any specific deficits. And it is very important to intervene early, because of these functional impairments. If intervention occurs earlier, these children are at reduced risk for school failure and having major social problems. In some cases a child’s cognitive difficulties may not become evident in school until several years after bipolar disorder has been diagnosed, so parents might want to be particularly alert for any signs of neuropsychological issues.

This interview is one in an ongoing series of profiles of scientists working to improve the diagnosis and treatment of children with early-onset bipolar disorder.

The following The Balanced Mind Foundation writers contributed to this interview:
Jessica Solodar, and Martha Hellander.