Pediatric Bipolar Disorder: A Brain Illness
PEDIATRIC BIPOLAR DISORDER: A BRAIN ILLNESS
When teachers and school administrators witness students exhibiting conduct such as tantrums, defiance, refusals to do work, and school avoidance, they typically address the conduct as a behavioral problem that can be eliminated with traditional behavioral modification practices. However, in a child with bipolar disorder, the normal rules do not always apply.
Many of the objectionable behaviors are actually due to neurological instability in the brain, rather than willful conduct. Often the behavior is a secondary response to some stressor, which leads to overwhelming frustration, anxiety, sadness or anger that the child cannot control. With an understanding of the biological underpinnings of bipolar disorder, it is possible to appreciate the degree to which behavior is influenced by the physiology of the brain. These behaviors can then be viewed as possible clues to a child’s current level of functioning, wellness, and stress. In your role as parent advocate, you will likely need to make this point more than once.“
The more I learn about bipolar disorder, the more I can help my daughter. Whether I am at the psychiatrist’s office, the pediatrician, or an IEP meeting, a strong understanding of bipolar disorder has served me well. I don’t try to be know it all, but I do try to learn whatever I can when the opportunity presents itself. –Karen, mother to Paige, age 5
Children At-Risk: Children with bipolar disorder are at risk for school failure, substance abuse, and suicide. The lifetime mortality rate of bipolar disorder from suicide is higher than that for some childhood cancers.
Depression: According to the National Institute of Mental Health (NIMH), more than 1.5 million children under the age of 15 are severely depressed. Bipolar disorder in children often begins with major depression, marked by not wanting to play, chronic irritability and sadness. Preschoolers may talk of wanting to “make myself dead.”
Early Onset: Fifty-nine percent of adults with bipolar disorder surveyed by the National Depressive and Manic-Depressive Association in 1993 reported that symptoms of their illness appeared during or before adolescence. The time between onset of symptoms and proper treatment is often 8-10 years, longer for pediatric-onset cases.
Pediatric Bipolar Disorder and ADHD: The symptoms for bipolar disorder often resemble symptoms of ADHD, with some important distinctions. About 15% of children diagnosed with ADHD may also have bipolar disorder. Bipolar disorder may first emerge with an episode of depression. Treatment with stimulants or antidepressants may trigger mania or mixed states in children with bipolar disorder or a family history of the illness.
MAJOR SYMPTOMS OF PEDIATRIC BIPOLAR DISORDER
Informed parents are simply more effective in advocating for their children. –Tasha, school psychologist and mother to Nafisa, age 8
Until recently, doctors rarely diagnosed bipolar disorder in childhood. They were unaware that the presentation of mood disorder symptoms in children usually differs from the more widely recognized adult presentation. Symptoms may present during infancy or early childhood, or may suddenly emerge in adolescence or adulthood.
Bipolar disorder influences mood, energy, thinking and behavior. Unlike adults, who experience episodes of distinct “highs” and lows,” many children with the disorder have an ongoing, continuous mood disturbance that is a mix of mania and depression. This produces chronic irritability and a few periods of wellness or clearly discernible episodes.
Mothers often report that children later diagnosed with the disorder seemed extraordinarily clingy, and from a very young age often had uncontrollable, seizure-like tantrums or rages out of proportion to any event. The word “no” often triggered these rages. Many children with this disorder exhaust their self-control during the school day. Therefore, they may exhibit this much more aggressive behavior in the relative safety and privacy of the home.
In adult bipolar disorder, a person’s mood cycles in well-defined phases that can last for hours, days, or months. In most children, the mood cycles may be less defined. It is not uncommon for children to cycle many times a day. Researchers believe that bipolar disorder is a spectrum disorder and have identified our subtypes of the disorder. These subtypes differ in the intensity and duration of mood episodes.
For some children, a loss or other traumatic event may trigger a first episode of depression or mania. Later episodes may occur independently of any obvious stresses, or may worsen with stress. Puberty is a time of higher risk for the onset or worsening of symptoms. In girls, the onset of menses may trigger the illness, and symptoms often vary in severity with the monthly cycle.
It is theorized that once the illness starts, episodes tend to recur and worsen without treatment. The theory is is called the “kindling effect”. Graham Gooddard, MD, first discovered the kindling effect in 1969 as he was studying seizure disorders. Robert Post, MD, of the National Institute of Mental Health is credited as first applying this theory to bipolar disorder. Researchers have discovered that children who are identified early and treated prior to multiple periods of cycling are less treatment resistant and appear to stabilize. The more mood episodes a person experiences, the more difficult it is to treat the disorder.
There is a high heredity rate for bipolar disorder. Some researchers estimate an 80% genetic linkage, meaning heritability is mostly due to genetic causes. Having the genetic predisposition for the illness does not automatically mean that the illness will manifest itself in the child. Kiki Chang, MD, of Stanford University, has completed a number of studies of offspring of parents with bipolar disorder. He has found some benefit to early intervention in offspring with early symptoms of bipolar disorder using mood stabilizers.
Symptoms of mania include:
- Elevated, expansive or irritable mood
- Decreased need for sleep
- Racing speech and pressure to keep talking
- Grandiose delusions
- Excessive involvement in pleasurable, but risky, activities
- Increased physical and mental activity
- Poor judgment
- In severe cases, hallucinations; and
Symptoms of hypomania include:
- Milder symptoms of mania with less impact on functioning
- Unlike mania, no psychosis (hallucinations or delusions indicative of loss of touch with reality)
Symptoms of major depression include:
- Pervasive sadness and crying spells
- Sleeping too much or inability to sleep
- Agitation and irritability
- Withdrawal from activities formerly enjoyed
- Drop in grades and inability to concentrate
- Thoughts of death and suicide
- Low energy
- Significant change in appetite
- Poor concentration, diminished ability to think, indecisiveness; and
- Feelings of worthlessness or exaggerated feelings of guilt
The symptoms of bipolar disorder overlap with some of the symptoms of other psychiatric disorders. This is particularly true of Attention Deficit/Hyperactivity Disorder (ADHD). Dr. Geller and colleagues in 2002 identified the presence of grandiosity, elated mood, flight of ideas, hypersexuality and decreased need for sleep as symptoms specific to bipolar disorder and not ADHD. In 1997, Dr. Wozniak and colleagues found that the symptoms of irritability, mood lability and aggression often seen in Pervasive Developmental Disorder (PDD) might be easily mistaken for bipolar mania. Comorbid behaviors are common in children diagnosed with pediatric bipolar disorder. This adds to the challenge of identifying and treating the disorder.
BRAIN CHEMISTRY AND BIPOLAR DISORDER
After Joshua was diagnosed with bipolar disorder, I kept hearing words that I didn’t understand… neuro this and neuro that. I finally decided it was time to learn the basics. Now, I can explain the prefrontal cortex to anyone who will listen. –Renee, mother to Joshua
To properly transmit information from one neuron (nerve cell) to another within the central nervous system, neurotransmitters—molecules carrying the chemical messages—must be generated, dispatched, and delivered to the right destination cells. A complex balance of brain chemicals allows the efficient passage of these messages within the system to produce organized thought, movement, emotion, and behavior.
Scientists have pinpointed six primary brain chemicals that are implicated in bipolar disorder. When the levels of these six substances are out of balance, the normal flow of information between neurons is disturbed, and a person’s normal activity, feelings, and thoughts cannot be processed in the usual way. In the brain of a person with bipolar disorder, several substances can be affected. Read more about brain chemicals in the drop down menu.
Serotonin: A neurotransmitter found in portions of the brain related to mood, anxiety, and cognition. A decrease in serotonin interferes with message delivery, causing constant, repeated, and exaggerated worry or tension. A decrease in serotonin is often seen as depression, which has such physical symptoms as fatigue, trembling, muscle tension, headaches, and nausea. A lack of adequate serotonin may be the cause when a child is tired, or complains of frequent stomach aches and headaches.
Dopamine: A neurotransmitter responsible for movement, attention, emotional response, and the ability to experience pleasure and pain. One area of the brain that uses dopamine is the basal ganglia, specifically the substantia nigra, which plays a major role in controlling body movements. An excess of dopamine is found to bring about disturbances in thought, mood, sense of self and feelings about one’s relationship with the external world. Delusions, disorganized thinking, and hallucinations can occur when dopamine is low. A child with irregular dopamine levels might behave in a very grandiose, belligerent manner, combative with the teacher, or may be fearful of activities for no apparent reason.
Noradrenaline (also called norepinephrine): A neurotransmitter that controls alertness and the sleep cycle, and regulates drive and motivation. When noradrenaline decreases, depressive symptoms increase, and drive and motivation fall. A child with inadequate noradrenaline may have difficulty starting and finishing assignments in class and at home, appearing disinterested in work, and seeming to be unwilling to put effort in or event trying to begin work. Some children, particularly during winter months, may even lack the ability to wake up and get dressed to attend school until pharmacological intervention can re-establish a balance of noradrenaline in the brain.
Monoamine oxidase: An enzyme that breaks down the brain chemicals noradrenaline, dopamine and serotonin. The action of this enzyme affects the availability of these other chemicals to perform their respective functions. In general, a shortage of monoamines results in depression; an excess can cause mania.
Gamma-aminobutyric acid (GABA): A neurotransmitter that acts as an inhibitor within the synapses of the brain. One GABA system is in the hippocampus and is involved in memory formation. GABA is believed to be involved in the movement of memories from short-term to long-term memory. This is believed to occur during a person’s sleep cycles. The child who has inadequate levels of GABA may have difficulty with memory consolidation and moving learned material from their working and short-term memory to long-term or permanent memory. In general, low GABA levels in the brain might lead to overactivity, such as mania.
Glutamate: Glutamate is an amino acid neurotransmitter that acts to excite neurons within the brain. Glutamate stimulates N-methyl-D-asperate (NMDA) receptors that are actively involved in learning and memory activities. Reduced levels of glutamate are found in major depression often associated with bipolar disorder. The over-stimulation of NMDA receptors can cause nerve cell damage or death. It is believed that during bipolar mania that the high levels of glutamate are responsible for some of the structural changes that occur in the prefrontal cortex. This further demonstrates the importance of early intervention and pharmacological stabilization.
AFFECTED PARTS OF THE BRAIN
Using increasingly sophisticated neuroimaging technologies, including Functional Magnetic Resonance Imaging (FMRI) and Positron Emission Tomography (PET) scans, scientists are now able to identify physical differences in the brain that are associated with bipolar disorder. While it has been known for some time that the disorder results from a “chemical imbalance”, researchers can now also identify specific areas of the brain that show changes in person with bipolar disorder.
Prefrontal cortex: The prefrontal cortex is located in the frontal lobe of the brain. It is one of the three sections that specialize in conscious voluntary behavior. The prefrontal cortex is the portion of the brain in which a person’s executive functions are regulated, including the ability to plan for the future, solve complex problems, and express and control emotions. It is in the portion of the brain that the skills needed to be successful in school are located.
Limbic system: The limbic system is a collective term referring to several parts of the brain, including the amygdale and the hippocampus. The limbic structures, which underlie the corpus callosum, are essential in the regulation of visceral (instinctive) motor activity and emotional expression.
Amygdala: The amygdale is an almond-shaped mass of gray matter that controls automatic, emotional and sexual behavior. It lies in the front part of the temporal lobe, in front of the hippocampus. In children with bipolar disorder, it appears that the amygdale is smaller than in children without the disorder. This further supports that positive and negative emotions are activated in this region of the brain.
Hippocampus: The hippocampus is a neural structure located in the limbic system, which is involved in motivation and emotion. As the “filing cabinet” of the brain, it performs the central role in the formation of memories. It consists of gray matter and is shaped like a sea horse.
Thalamus: The thalamus is a component of the forebrain that sends sensory information to the cerebral cortex. This structure helps make complex thought processes, emotions, and problem solving occur.
Basal nuclei (also known as basal ganglia): The basal nuclei is a group of cell bodies located in the white matter of the cerebral hemisphere, functioning primarily or organize motor behaviors.
Occipital lobe: The occipital lobe is located in the back of the brain. It is responsible for sending and receiving visual messages and information. Deficits in the occipital lobe appear to be involved in the visual-perceptual deficits that are often seen in children with bipolar disorder. Children with visual-perceptual deficits complain of eyestrain. They have difficulty with reading, letter formation and writing, and tracking between a horizontal and/or vertical plane. They also have difficulty completing fine motor tasks such as gluing, cutting, and writing.