In a symposium at the 2014 meeting of the International College of Neuropsychopharmacology, four researchers shared insights on children who are at high risk for bipolar disorder because they have a parent with the disorder.
Researcher John Nurnberger has been studying 350 children of parents with bipolar disorder in the US and 141 control children of parents with no major psychiatric disorder, following the participants into adolescence. He found a major affective disorder in 23.4% of the children with parents who have bipolar disorder and 4.4% of the controls. Of the at-risk children, 8.5% had a bipolar diagnosis versus 0% of the controls.
Nurnberger found that disruptive behavior disorders preceded the onset of mood disorders, as did anxiety disorders. These diagnoses predicted the later onset of bipolar disorder in the at-risk children, but not in the controls. A mood disorder in early adolescence predicted a substance abuse disorder later in adolescence among those at risk.
In genome-wide association studies, the genes CACNA1C and ODZ4 are consistently associated with risk of bipolar disorder, but with a very small effect size. Therefore, Nurnberger used 33 different gene variants to generate a total risk score and found that this measure was modestly effective in identifying relative risk of developing bipolar disorder. He hopes that using this improved risk calculation along with family history and clinical variables will allow better prediction of the risk of bipolar onset in the near future.
Researcher Ann Duffy reported on her Canadian studies of children who have a parent with bipolar disorder and thus are at high risk for developing the disorder. In contrast to the studies of Nurnberger et al. and many others in American patients, she found almost no childhood onset of bipolar disorder before late adolescence or early adulthood. She found that anxiety disorders emerge first, followed by depression, and then only much later bipolar disorder. Bipolar disorder occurred with comorbid substance abuse disorders in only about 10-20% of cases in 1975, but substance abuse increased to 50% of bipolar cases in 2005. The incidence of comorbid substance disorder and the year at observation correlated strongly, indicating a trend toward increased substance abuse over the 30-year period.
Duffy found that having parents who were ill as opposed to recovered was associated with a more rapid onset of mood disorder in the offspring, usually in early adulthood. Duffy emphasized the need to intervene earlier in children of parents with bipolar disorder, but this is rarely done in clinical practice. Read more
Korea, like the US, has a moderate incidence of childhood-onset bipolar disorder among children who are at high risk because they have a parent with bipolar disorder. In a recent study by Young-Sun Cho et al. presented at the 2014 meeting of the International College of Neuropsychopharmacology (CINP), 59 out of 100 children with a parent who had been diagnosed with bipolar disorder met the criteria for a mental disorder themselves.
Mood disorders were most common. Of the 59 children with mental disorders, 22 were diagnosed with bipolar disorder, and 16 were diagnosed with a depressive disorder. Others included four with attention deficit hyperactivity disorder (ADHD), four with an anxiety disorder, two with disruptive behavior disorders, one with a tic disorder, one with an autistic disorder, and one with schizophrenia and an anxiety disorder.
Editor’s Note: In contrast to studies in Germany, Switzerland, the Netherlands, and Canada, where few children are diagnosed with bipolar disorders (even among those who are at high risk because of a family history of bipolar disorder), 22% of high-risk children in Korea were diagnosed with bipolar disorder. This is comparable to or higher than rates at which high-risk children in the US are diagnosed with bipolar disorder. Studies from both the Bipolar Collaborative Network (in which this editor Robert Post is an investigator) and researcher Boris Birmaher et al. found that parents with bipolar disorder often had a variety of other disorders, such as anxiety, alcohol abuse, or substance abuse. These other illnesses also increase the risk of early-onset bipolar disorder in offspring, and this may account for the higher incidence of early-onset bipolar disorder among high-risk children in the US.
Muffy Walker gave an inspirational talk at the 2014 meeting of the International Society for Bipolar Disorders about the International Bipolar Foundation (IBPF, formerly known as the California Bipolar Foundation) she started with three other mothers of children with bipolar disorder. The organization advocates for better understanding and treatment of the illness in children. Treatment is too often delayed and insufficient, as was the case with Walker’s son, who started having trouble at age four and was diagnosed with post-traumatic stress disorder (PTSD), oppositional defiant disorder (ODD), attention-deficit hyperactivity disorder (ADHD), and conduct disorder (CD) before he became severely manic while taking the antidepressant fluoxetine (Prozac). The foundation has a monthly e-newsletter. Their website is http://ibpf.org.
At the 2014 meeting of the International Society for Bipolar Disorders, researcher B.N. Kim discussed symptoms that could distinguish between bipolar disorder and attention deficit hyperactivity disorder (ADHD) in childhood. Both disorders are characterized by decreased attention, concentration, and frustration tolerance, and increased activity, impulsiveness, and irritability.
Kim shared several differential symptoms that are more indicative of a bipolar diagnosis and that are inconsistent with a simple ADHD diagnosis (and this editor Robert Post has added several more). Signs and symptoms that suggest bipolar disorder and not ADHD include: decreased need for sleep, brief and extended periods of euphoria, hypersexuality, delusions, hallucinations, suicidal or homicidal impulses and/or actions, extreme aggression, and multiple areas of extreme behavioral dyscontrol. ADHD, on the other hand, is characterized by more difficulty focusing attention, and by less extreme symptoms in general.
The Pittsburgh Bipolar Offspring study, led by Boris Birmaher of the University of Pittsburgh, investigated risk of illness in the offspring of parents with bipolar disorder. The study included 233 parents with bipolar disorder and 143 controls. In addition to bipolar disorder, parents in the study had many other disorders, including anxiety (70%), panic (40%), a disruptive behavior disorder (35%), attention-deficit hyperactivity disorder or ADHD (25%), and substance use disorder (35%).
The offspring averaged age 12 at entry in the study. Offspring of parents with bipolar disorder had more illness than those of control parents, including bipolar spectrum disorders (10.6% versus 0.8%), depression (10.6% versus 3.6%), anxiety disorder (25.8% versus 10.8%), oppositional defiant disorder or conduct disorder (19.1% versus 8.0%), and ADHD (24.5% versus 6.7%). Of these differences, only bipolar spectrum disorders and anxiety were statistically significant after correcting for differences in the parents’ other diagnoses.
Two factors predicted bipolar spectrum disorders in the offspring: younger age of a parent at birth of child and bipolar disorder in both parents. Older children and those with diagnoses of anxiety or oppositional defiant disorder were more likely to be diagnosed with bipolar disorder.
On long-term follow-up that continued on average until the offspring reached age 20, 23% of those participants who had a parent with bipolar disorder developed any type of bipolar disorder, versus only 1.2% of the children of controls. Of these 23%, about two-thirds had a depressive episode prior to the onset of their bipolar disorder.
Of the offspring of parents with bipolar disorder who developed a bipolar spectrum illness, 12.3% developed bipolar I or II disorders, while 10.7% were diagnosed with bipolar not otherwise specified (NOS). Of those with bipolar NOS, which some consider to be sub-threshold bipolar disorder, about 45% converted to a bipolar I or II diagnosis after several years of prospective follow-up. These data, along with the finding that children with bipolar NOS are highly impaired and take more than a year on average to remit, stress the importance of vigorously treating this subtype, even if it does not meet the full threshold for bipolar I or bipolar II.
Birmaher indicated that although about 50% of the offspring of a bipolar patient had no diagnosis, the high incidence of multiple psychiatric difficulties developing over childhood and adolescence spoke to the importance of attempts at early intervention and prevention. Studies of effective treatment and prevention strategies are desperately needed. So far only family focused therapy (FFT), an intervention developed by researcher David Miklowitz, has shown significant benefits over standard treatment in children with a positive family history of bipolar disorder who already have a diagnosis of anxiety, depression, or bipolar not otherwise specified.
Omega-3 fatty acids (especially the type known as DHA) are essential for brain development and functioning, but most people eating a modern western diet consume low amounts of these compared to omega-6 fatty acids. Omega-3s are anti-inflammatory while omega-6s are pro-inflammatory. A large UK study published in the journal PLOS One in 2013 reported that healthy 7- to 9-year-olds with lower levels of omega-3 long-chain polyunsaturated fatty acids in their blood (including DHA, DPA, and EPA) had lower reading ability and working memory, and also had more behavior problems.
The oils in fish are the best source of omega-3 fatty acids, and most of the children with poor reading ability in the study fell short of the UK nutritional guideline that recommends eating two portions of fish per week.
Girls in the study had more dramatic deficits in omega-3 levels than boys. In adults, women tend to metabolize long chain polyunsaturated fatty acids more easily than men, but this difference is driven by hormones, and because the girls in the study had not yet reached child-bearing age, they did not reflect this benefit.
Omega-3 deficits in children have been connected with attention deficit hyperactivity disorder (ADHD), and supplementation with extra omega-3 fatty acids in the diet has led to improvements in ADHD.
Iron deficiency is the most prevalent nutritional deficiency in industrialized countries and can cause problems with cognitive and intellectual development. New research published in the journal BMC Psychiatry shows that it has psychiatric ramifications as well. Children and adolescents with iron deficiency anemia are at greater risk for psychiatric disorders, including depression, bipolar disorder, anxiety, and autism.
Iron supplementation should be implemented in children with iron deficiency anemia in order to prevent any possible psychiatric repercussions, and similarly, psychiatrists should check iron levels in young patients with psychiatric disorders.
Iron provides myelin for white matter in the brain and plays a role in the function of neurotransmitters.
Most children recover from an episode of bipolar disorder after a considerable period of time, but the majority eventually relapse. At the 2013 meeting of the American Academy of Child and Adolescent Psychiatry (AACAP), Boris Birmaher of the University of Pittsburgh presented new data on the long-term prospective course of bipolar disorder in 255 children with bipolar I, 30 children with bipolar II, and 153 children with bipolar NOS (not otherwise specified), who together had an average age of onset of 9.3 +/- 3.9 years. The children participated in the study for an average of 8 years. Most of the children (81.5%) recovered from their episode, but only after an average of 2.5 years of follow up treatment. Yet 62.5% of those who recovered experience a recurrence after an average of 1.5 years.
Editor’s Note: It takes a long, long time to achieve recovery, and longer for bipolar NOS (more than 2 years on average) than for either Bipolar I or II (about 1.8 years). However, the high rate of relapse within 1 to 2 years is equally disturbing. These data are similar to those in many other prospective follow up studies of children, and suggest that it is important for parents to be aware that this illness is difficult to treat, and good results within weeks are not likely to be the norm. At the same time, 43% of the children with a bipolar diagnosis eventually achieved euthymia (wellness) in the longer term, so there is cause for some optimism.
Four Trajectories in Children with Bipolar Illness
Birmaher described four different long-term,trajectories observed over an average of 8 years of follow up with 438 children with bipolar disorder.
- Predominately euthymic (24%)
- Ill early then much improved (19%)
- Mild to moderately ill—euthymic only 47% of the time (34.6%)
- Predominantly ill—euthymic 11.5% of the time (20.3%)
The predominantly well group (1) was associated in a univariate analysis with a later onset of illness, higher socio-economic status, less conflict, fewer stressors, less sexual abuse, fewer anxiety and ADHD comorbidities, and less medication (including stimulant use). In a multivariate analysis, this group was independently associated with less severe depression/mania, less suicidal ideation, less substance use, less sexual abuse, and less family history of mania and substance abuse.
This group had the best functioning, almost to 80 on the Children’s Global Assessment Scale (C-GAS). In comparison, despite considerable time euthymic for groups 2 and 3, these children still had considerable functional impairment, in the realm of 65 on the C-GAS scale. Even in Group 1, about half of the children had low C-GAS scores.
Birmaher suggested the importance of trying to find ways to delay the onset of the illness (to graduate more children into the good prognosis group) and allowing them time to develop socially and educationally and graduate from high school. Potential preventive strategies could include omega-3 fatty acids, more time spent exercising, good sleep hygiene, family focused therapy (FFT), dialectic behavior therapy, treating subsyndromal depression, and even treating parents with mood disorders to complete remission (which has been shown to improve behavioral health in offspring).
Editor’s Note: As this editor Post, Chang, and Frye wrote in the Journal of Clinical Psychiatry in 2013, beginning to study the effectiveness of these kinds of early primary and secondary prevention strategies in children who can now be readily identified clinically as at risk for a mood disorder, should be given the highest priority.
Children who have at least one parent with a bipolar or unipolar disorder, some further environmental risk factors (such as adversity in early childhood), and early symptoms of depression, anxiety, or prodromal bipolar disorder are at very high risk for bipolar disorder, and there is an urgent need for randomized studies (even open ones) of safe potential preventive strategies for these children.
Omega-3 fatty acids in particular have a strong record of safety, compelling rationale for use in bipolar disorder, and have already been shown to have significant preventive effects in decreasing the transition from early prodromal psychosis to full-blown schizophrenia.
Research on early-onset bipolar disorder has often hinged on identifying the key characteristics of the disorder. At a symposium on the course of bipolar disorder in children at the 2013 meeting of the American Academy of Child and Adolescent Psychiatry (AACAP), Jeff Hunt of Brown University discussed findings from COBY, the Collaborative Child Bipolar Network. He described the course of illness in 446 children with bipolar disorder, including 10% who had irritability at baseline, 15% who had elated mood at baseline, and a majority (75%) who had both irritability and elation at baseline.
Most factors such as positive family history of bipolar illness and comorbidities including attention deficit hyperactivity disorder (ADHD) did not differ across the three groups. The three subtypes (irritable, elated, or mixed) did not remain stable, and most of the children eventually converted to the combined irritable and elated subtype. These data contrast with those of Ellen Liebenluft et al., who found that those with severe mood dysregulation or chronic irritability (but not other key characteristics of bipolar disorder) did not go on go on to receive a bipolar diagnosis and tended not to have a family history of bipolar disorder.
Among the hundreds of posters, workshops, clinical perspectives, and symposia presented over five days at the 2013 meeting of the American Academy of Child and Adolescent Psychiatry (AACAP), there were almost no posters or presentations on new approaches to treatment (either with drugs or therapy) for children with bipolar disorder.
As we have repeatedly emphasized in the BNN and in research publications, this deficiency has adverse consequences for the many hundreds of thousands of children and adolescents in the US with unequivocal diagnoses of bipolar disorder. Suicide is now the second leading cause of death in adolescents 13 to 17 years of age in the US. Most of these young people have a mood disorder. Bipolar disorder carries with it not only a substantial risk of suicide, but also the potential for a lifetime of dysfunction, disability, and medical comorbidity if it is inadequately treated.
Please advocate for more treatment research for childhood onset bipolar disorder. A whole generation of children, their parents, and their physicians desperately need more treatment information.