Genetic inheritance is not everything, according to J. Craig Venter, pioneering genetic scientist responsible for sequencing the human genome in 2001:
“Human biology is actually far more complicated than we imagine. Everybody talks about the genes that they received from their mother and father, for this trait or the other. But in reality, those genes have very little impact on life outcomes. Our biology is far too complicated for that and deals with hundreds of thousands of independent factors. Genes are absolutely not our fate. They can give us useful information about the increased risk of a disease, but in most cases they will not determine the actual cause of the disease, or the actual incidence of somebody getting it. Most biology will come from the complex interaction of all the proteins and cells working with the environmental factors, not driven directly by the genetic code.”
George Koob, Director of the National Institute on Alcohol Abuse and Alcoholism, discussed the neuroscience of chronic drug use at the 2015 meeting of the Society of Biological Psychiatry. His basic message was that chronic drug use is associated with A) loss of the reward value of the drug and B) a progressive increase in dysphoria and stress when off the drug. Both factors drive craving and drug seeking.
Access to high as opposed to moderate doses of a drug lead to an escalation in drug intake, and associated persistent increases in withdrawal dysphoria, which Koob called “the dark side.”
Koob explained that a month of detoxification is not sufficient, and that people quitting a drug need more time to let dopamine increase and to let levels of corticotropin releasing factor (CRF), which drives the anxiety and dysphoria of withdrawal, normalize. He stressed that for people addicted to opiates, it is important to taper levels of the drug to minimize withdrawal symptoms.
In addition to CRF, dynorphin also plays a role in chronic drug abuse. This opiate peptide acts at kappa opiate receptors and is associated with anxiety, dysphoria, and psychosis as opposed to morphine, which acts at mu opiate receptors and is associated with euphoria and decreased pain. Koob found that administration of the kappa opiate antagonist norbinaltorphimine (nor-BNI) blocks dose escalation of methamphetamine and brings abstinence-related compulsive drug seeking back to baseline.
In a longitudinal study of 1,037 people born in Dunedin, New Zealand in 1972 and 1973, most participants with attention deficit hyperactivity disorder (ADHD) in adulthood did not have the disorder as children. The study by Terrie E. Moffitt and colleagues in the American Journal of Psychiatry is the first prospective longitudinal study to describe the childhood of adults with ADHD.
When the study participants were children, about 6% were diagnosed with ADHD (mostly males). These children also had comorbid disorders, neurocognitive deficits, multiple genes associated with risk for ADHD, and some life impairment when they reached adulthood.
In adulthood, about 3% of the participants had ADHD (roughly equal between men and women), and 90% of these participants had no history of ADHD in childhood. The participants with ADHD in adulthood also had substance dependence and life impairment, and had sought treatment for the disorder. The researchers were surprised to find that these participants with adult ADHD did not show neuropsychological deficits in childhood, nor did they have the genetic risk factors associated with childhood ADHD.
If the findings of this study are replicated, researchers will have to rethink the current classification of ADHD as a neurodevelopment disorder that begins in childhood, and begin to determine how adult ADHD develops.
Editor’s Note: Before the publication of this article, most investigators (including this editor Robert M. Post) thought that virtually all ADHD in adulthood evolved from the childhood disorder, and if it did not begin in childhood, the diagnosis was suspect. I still believe the ADHD that appears in adulthood in patients with bipolar disorder is likely attributable to residual depression and anxiety or hypomania and that more concerted treatment of the patient to full remission will often result in much better attention, concentration, and ability to follow through and stay on task.
Verbal Abuse in Childhood, Like Physical and Sexual Abuse, Linked to Earlier Onset and More Difficult Course of Bipolar Disorder
Earlier research has shown that childhood adversity is linked to earlier age of onset of bipolar disorder and more difficult course of illness. Physical and sexual abuse are associated with both earlier age of onset and more difficulties such as anxiety disorders and substance abuse. Now, new research by this editor (Robert M. Post) and colleagues links verbal abuse (even in the absence of physical and sexual abuse) to earlier onset of bipolar disorder and to more severe and complicated course of illness.
The study, published in the journal Bipolar Disorders, was based on the self-reports of 634 adult outpatients with bipolar disorder at four sites in the US. These participants were interviewed about their history of illness and the frequency of adverse events they experienced in childhood, adolescence, and adulthood, including physical, sexual, and verbal abuse. Twenty-four percent of these participants reported having experienced verbal abuse occasionally or frequently in childhood, but not other forms of abuse, while another 35% had a history of verbal abuse as well as physical or sexual abuse, for a total of 59% with a history of verbal abuse.
The greater the frequency of verbal abuse in childhood, the earlier the average age of onset of bipolar disorder. Participants with no history of abuse had a mean age of onset of 20.6 years, but verbal abuse by itself reduced the mean age of onset to 16.5 years, and verbal abuse plus sexual abuse reduced the mean age of onset to 15.3 years. (The mean age of onset for participants who experienced sexual abuse alone was 17.5 years.) It was impossible to determine the combined effect of verbal and physical abuse because verbal abuse was almost always present when physical abuse occurred. For the 14% of the participants who had experienced verbal, physical, and sexual abuse in childhood, the mean age of onset of bipolar disorder was 13.1 years.
Those who were verbally (but not physically or sexually) abused in childhood had more anxiety disorders, drug abuse, and rapid cycling than those who were not abused, but not more alcohol abuse. Those who were verbally abused also showed increasing severity of illness, including increased frequency of cycling.
Genetics can also play a role. Having a parent with a mood disorder also contributed to an earlier age of onset of bipolar disorder.
Editor’s Note: Researcher David J. Miklowitz and colleagues have shown that family focused therapy (FFT), which emphasizes illness education and communication enhancement within the family, is more effective than treatment as usual for children with a family history of bipolar disorder and a diagnosis of depression, cyclothymia, or bipolar not otherwise specified (BP NOS).
FFT was particularly effective in reducing symptoms in children from families with high expressed emotion, suggesting that this kind of family-based intervention could reduce levels of verbal abuse.
The timeframe during which recovery and recurrence occur in people with a first episode of mania are somewhat variable. A meta-analysis by Andréanne Gignac and colleagues published in the Journal of Clinical Psychiatry in 2015 offers some new information. The meta-analysis included eight studies with a total of 734 participants in a first episode of mania. Syndromal recovery rates (when patients no longer met diagnostic criteria for bipolar disorder) were 77.4% at six months after first episode of mania and 84.2% at one year after. However, some symptoms lingered, and only 62.1% of patients reached a period of symptomatic recovery within one year.
Recurrence rates were 25.7% within six months, 41.0% within one year, and 59.7% by four years. Those who were younger at the time of the first episode were at higher risk for relapse within one year.
Editor’s Note: On the positive side, most recovered, but on the negative side, at one year, 60% remained symptomatic and 40% had a recurrence. What is not clear is how intensively patients were treated and monitored. The main message of this study is that a first episode of mania is not trivial and deservces concerted acute and long-term treatment. When expert multimodal treatment is given results are vastly more superior than treatment as usual (Kessing et al. British Journal of Psychiatry 2013).
Research on early-onset bipolar disorder sometimes lumps childhood-onset in with adolescent onset. Researcher Terence Ketter et al. explored differences in illness among 502 patients at the Stanford Bipolar Disorder Clinic. The 107 patients with childhood onsets (before age 13) had a more difficult course of illness in almost all domains compared to the 238 patients with adolescent onsets (age 13–18) or the 157 patients with illness onset in adulthood (after age 18).
Considered separately, both patients with childhood-onset illness and patients with adolescent-onset illness had more comorbid anxiety disorders, alcohol use disorders, eating disorders, prior suicide attempts, rapid cycling in the prior year, and at least five mood episodes over the course of their lifetimes than those patients whose illness began in adulthood. Patients whose illness began in childhood had higher rates of each of these unfavorable illness characteristics and were more likely to have a first-degree relative with a mood disorder.
These data mirror those from the Bipolar Collaborative Network in which this editor (Robert Post) is an investigator, and the larger STEP-BD network led by Perlis et al. All three suggest that in the US, two-thirds of the bipolar disorder seen in adults begins in childhood and adolescence, with about a quarter beginning before age 13.
Ketter suggests that research should not combine childhood and adolescent onset illnesses, which come with different rates of anxiety, alcohol, and eating disorder comorbidity, rapid cycling, and prior episodes. The statistical relevance of some findings can be diluted when the two groups are combined.
Editor’s Note: However, the primary message is that childhood onset bipolar disorder is a more severe version of the illness that deserves greater attention, treatment, and research so that its course can be made more benign. It is a problem that there are no Federal Drug Administration–approved treatments for children under 10 years of age with bipolar disorder.
At the 2014 meeting of the International Society for Bipolar Disorder, researcher Kiki Chang discussed Pediatric Acute Onset Neuropsychiatric Syndromes (PANS), a newly identified phenomenon in which children suddenly develop obsessive compulsive disorder (OCD) and/or a restrictive eating disorder following an infection or other process that stimulates an immune/inflammatory reaction in the brain. A similar phenomenon, Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS), was initially identified by Susan Swedo of the National Institute of Mental Health (NIMH) and refers to children (usually under 6–10 years old) who develop OCD and/or tics following a case of strep throat or scarlet fever.
PANS may have an autoimmune component. In addition to acute onset of OCD and eating restriction, other symptoms include mood episodes (depression, mania), high aggression/irritability, anxiety (particularly separation anxiety), cognitive problems (ADHD, handwriting regression), regressive behaviors, and somatic signs such as sleep difficulties and urinary urgency. Biological abnormalities may include: abnormalities in red blood cell sedimentation rate, elevated C-reactive protein (CRP), high Anti DNase B and/or Antistreptolysin O (ASO) titers (anti-Streptococcus antibodies), mycoplasma IgG or IgM antibodies (signs of some types of pneumonia), ANA (antinuclear antibodies, sign of an autoimmune disease), ferritin (a protein that stores iron), copper, and a panel of tests (the Cunningham Panel) by the company Moleculera Labs that measures antibodies for four neural antibodies (dopamine D1 receptors, dopamine D2 receptors, lysoganglioside (LysoGM-1), and tubulin) and calcium/calmodulin-dependent protein kinase activity (CaMKII).
PANS is three times more likely to affect males than females, and in the Stanford PANS Clinic sample of 50 youth, PANS was associated with strep infections (65%), mycoplasma bacteria (13%), viral or urinary tract infection (58%), and ear and other infections in 16%.
Symptoms included OCD (86%), anxiety (92%), mood disturbance (88%), and aggression (82%).
Treatments include steroids, the immunosuppressant mycophenolate, intravenous immunoglobulin (IVIG), plasma exchange, the tumor necrosis factor blocker infliximab, and sometimes the antibiotic amoxicillin.
Chang also described a case in which a 15-year-old developed minocycline-induced OCD and acute onset of severe mania that included urinary incontinence and was unresponsive to medication. The patient had elevated ANA, anti-thyroid antibodies, and reduced complement C4 proteins, along with elevated antibodies to dopamine D1 and D2 receptors, LysoGM-1, and tubulin.
While the reasons why one person develops bipolar disorder and another does not remain mysterious, the current thinking is that genes contribute some risk while immunological abnormalities contribute other risks. Researchers have identified certain antibodies whose levels spike during an episode of mania, as if the patient is having an immune reaction. These are referred to as biomarkers or inflammatory markers.
While various biomarkers for mania have been identified, until recently their effects had only been examined independently. A 2013 article by Dickerson et al. published in the journal PLOS ONE examined four biomarkers in combination. Each was a type of antibody: to the NR peptide of the NMDA receptor, to gliadin (a protein derived from gluten), to Toxoplasma gondii (a parasitic protozoan), and to Mason-Pfizer Monkey Virus. Measures of these four types of antibodies made up a combined inflammation score for participants in the study.
The study compared 57 patients presenting with a manic episode with 207 non-psychiatric controls and 330 patients who had had recent onset of psychosis, schizophrenia, or bipolar depression. The combined inflammation score of the mania group was significantly higher than the other groups at the time of hospital admission and at the time of evaluation several days later. It had returned to normal (i.e. not different from the other groups) at followup six months later, although those with the highest combined inflammation scores were at risk for re-hospitalization during that period.
The findings of this study suggest that hospitalization for mania is associated with immune activation, and the level of this activation predicts subsequent re-hospitalization. Treatments for mania that target this inflammatory response should be investigated.
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.
Many children with bipolar disorder also present with other comorbid Axis I psychiatric illnesses. Now it seems that the worsening of these comorbidities, such as attention-deficit hyperactivity disorder (ADHD) or an anxiety disorder, can signal a more difficult course of bipolar illness itself. 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), Shirley Yen from Brown University discussed findings on comorbidities of childhood onset bipolar disorder from COBY, the Collaborative Child Bipolar Network. Upon study entry, 60% of children with bipolar disorder also had ADHD, 40% had oppositional defiant disorder (ODD), 39% had an anxiety disorder, 12.5% had both oppositional defiant disorder and a conduct disorder, and 9% had a substance abuse disorder.
The prevalence of most of these comorbid illnesses increased over time (e.g. anxiety disorder rates increased from 39% to 62%). The illnesses were also related to the time it took participants to achieve recovery (eight consecutive weeks well), and the time until a recurrence of a depressive or manic episode.
Increases in anxiety were linked to longer time to achieve recovery and a shorter time to a recurrence. Increases in ADHD were linked to a more rapid onset of a depressive recurrence. Increases in oppositional defiant disorder and conduct disorder had no relationship with either remission or recurrence. Increases in substance abuse disorders were linked to a longer time to recover from a manic episode. Thus, worsening of the comorbid conditions had definite consequences for both recovery and recurrence.