ADHD Common in People with Mood Disorders
In a meta-analysis published in the journal Acta Psychiatrica Scandinavica in 2021, researcher Andrea Sandstrom and colleagues reported that people with mood disorders had a three times higher incidence of attention-deficit hyperactivity disorder (ADHD) than people without mood disorders. ADHD was also more likely to occur in people with bipolar disorder than in people with major depression. The comorbidity is most common in childhood, less so in adolescence, and lowest in adulthood.
Based on 92 studies including a total of 17,089 individuals, the prevalence of ADHD in people with bipolar disorder is 73% in childhood, 43% in adolescence, and 17% in adulthood. Data from 52 studies with 16,897 individuals indicated that prevalence of ADHD in major depressive disorder is 28% in childhood, 17% in adolescence, and 7% in adulthood.
Editor’s Note: A key implication of this research is that there is a huge overlap of bipolar disorder and ADHD in childhood, and that physicians need to specifically look for bipolar symptoms that are not common in ADHD to make a correct diagnosis. These include: brief or extended periods of mood elevation and decreased need for sleep in the youngest children; suicidal or homicidal thoughts and threats in slightly older children; hyper-sexual interests and actions; and hallucinations and delusions. When these are present, even when there are also clear-cut ADHD symptoms, a clinician must consider a diagnosis of bipolar disorder and treat the child with mood stabilizers prior to using stimulants or other traditional ADHD medications.
Conversely, physicians should be aware of the much lower incidence of ADHD in adolescents and adults with bipolar disorder. Here one should first make sure that the apparent ADHD symptoms of hyperactivity, inattention, poor concentration, etc. do not result from inadequately treated mania and depression, and if they do, treat these symptoms to remission prior to using traditional ADHD medications.
Exercise in Childhood Decreases Depression Symptoms Two Years Later
A 2017 study in the journal Pediatrics found that higher rates of moderate to vigorous physical activity at ages six and eight was linked to fewer symptoms of depression at age 10.
The study included 795 six-year-olds who were tracked for four years. Their physical activity was measured by accelerometry, the same type of technology found in smartphones and other consumer products that can track a person’s daily steps. Depression symptoms were assessed via interviews with the children and their parents.
While exercise seemed to reduce depression symptoms, sedentary behavior did not predict later depression.
Traumatic Events in Childhood Linked to Shorter Telomeres
Telomeres are bits of DNA at the end of chromosomes that protect the DNA as it replicates. Shorter telomeres have been linked to aging and increases in multiple types of medical and psychiatric disorders. A 2016 article in PNAS, the Proceedings of the National Academy of Sciences of the United States of America, reported that cumulative life adversity and particularly stressful or traumatic events in childhood, predict shorter telomere length.
The study by Eli Puterman and colleagues included 4,590 individuals from the US Health and Retirement Study who reported stressful events that had experienced. A single experience of adversity was not linked to short telomeres, but lifetime cumulative adversity predicted 6% greater odds of having shorter telomeres. This result was mainly explained by adversity that occurred in childhood. Each stressful or traumatic event in childhood increased the odds of short telomeres by 11%. These were mostly social or traumatic experiences rather than financial stresses.
Early Life Stress Affects Volume of the Hippocampus
New research shows that there are crucial periods of early life in which a stressful event can reduce hippocampal volume in adolescence. In a study presented at the 2016 meeting of the Society of Biological Psychiatry, Kathryn L. Humphreys and colleagues found that children who experienced a significant stressor before age 8 had smaller hippocampi in early adolescence than children who did not have a significant stressor early in life.
The severity of the stressors that occurred when children were between the ages of 0 and 2 predicted the volume of the hippocampus later in life. This was true to a lesser extent for stressful events that occurred between the ages of 3 and 5. No effect was seen for stressful events that took place between the ages of 6 and 8.
The period of sensitivity to stressful events between ages 0 and 2 and its effects on hippocampal volume could influence a variety of psychiatric outcomes in conditions such as depression and post-traumatic stress disorder (PTSD).
Emotional Abuse Increases Inflammation
Trauma in childhood is a risk factor for depression, and both childhood trauma and depression have been linked to increased inflammation. In a study presented at the 2016 meeting of the Society of Biological Psychiatry, Sarah R. Horn and colleagues found that emotional abuse in childhood predicted high levels of inflammation measured in the blood in adulthood.
Horn and colleagues took blood samples from 35 people with treatment-resistant depression and 28 healthy control subjects. The researchers measured inflammatory markers in the blood and also interviewed the participants about any physical, sexual, or emotional abuse they experienced in childhood. Among all the participants, emotional abuse was linked to elevated levels of several inflammatory markers, including interleukin-6, interleukin-10, interleukin-1a, interleukin-15, and fractalkine.
The researchers suggest that more research is needed to clarify the link between early trauma, depression, and inflammation. How elevated inflammation in people with a history of abuse may influence the effectiveness of different psychotherapies and medications for depression remains to be determined.
Psychiatric Symptoms in Childhood Linked to Struggles in Adulthood
Psychiatric illness is one of the most common health problems among children. A study by William E. Copeland and colleagues in the journal JAMA Psychiatry indicates that psychiatric symptoms and diagnoses in childhood can lead to struggles with health, the legal system, personal finances, and social functioning in early adulthood, even if the psychiatric symptoms themselves do not last.
The study included 1420 participants from 11 mostly rural counties in North Carolina, who participated in structured interviews up to six times between the ages of 9 and 16 to determine the existence of psychiatric symptoms and diagnoses. Of these, 1273 were assessed three times during young adulthood, at the ages of 19, 21, and 24–26, for any evidence of social, legal, financial, or health problems.
Participants who had had a childhood psychiatric disorder were six times more likely to have at least one adverse outcome in adulthood compared to participants with no history of psychiatric problems, and nine times more likely to have two or more adverse outcomes in adulthood. Those participants who had psychiatric symptoms that were not sufficient for a particular diagnosis were still three times more likely to have at least one adverse outcome in adulthood, and five times more likely to have at least 2 adverse outcomes. The cumulative number of psychiatric disorders to which a participant was exposed was the best predictor of adverse outcomes in adulthood.
Even moderate psychiatric problems in childhood can disrupt a person’s transition to adulthood. However, early treatment and prevention can help reduce the long-term impact of psychiatric illness. Parents of children (aged 2–12) with mood and behavioral symptoms are welcome to join the Child Network, a system for collecting weekly ratings of their children’s symptoms and displaying them longitudinally for the child’s doctor.
Childhood Maltreatment Associated with Suicide Attempts
A history of childhood maltreatment increases the risk that a person will attempt suicide. Different types of maltreatment, such as physical abuse, emotional abuse, sexual abuse, and neglect, often overlap. In a 2015 study in the Journal of Clinical Psychiatry, researcher Nicolas Hoertel and colleagues used data from an epidemiological survey of 34,653 Americans to clarify the mechanism by which maltreatment is linked to suicide risk.
Hoertel and colleagues found that childhood maltreatment in general was associated with an increased risk of attempting suicide and an earlier age at first suicide attempt. The analysis controlled for demographic characteristics and psychiatric diagnoses. Most of the risk came from effects that were shared across all the types of maltreatment. However, sexual abuse directly conferred an additional risk of suicide attempt.
In an earlier study of 648 outpatients with bipolar disorder by this editor Robert Post and colleagues (led by Gabriele Leverich), 34% had a history of suicide attempts, and these participants had a higher incidence of traumatic stressors in childhood and more stresses at illness onset than those without a history of suicide attempts. A history of sexual abuse in childhood was also linked to an increased risk of a serious suicide attempt in the earlier study, which appeared in the Journal of Clinical Psychiatry in 2003.
Link Between Childhood Trauma and Difficult Course of Bipolar Disorder Clarified
A collaboration between Norwegian and French researchers led by Bruno Etain has clarified the pathway by which childhood trauma is linked to worse outcomes among people with bipolar disorder. The researchers, who presented their work in a poster at the 2015 meeting of the Society of Biological Psychiatry, replicated earlier findings by this editor (Robert Post) that patients who experienced trauma as a child had a more adverse course of bipolar disorder. Etain and colleagues found a link between childhood trauma and an earlier age of onset of bipolar disorder, rapid cycling, suicide attempts, and cannabis misuse.
The researchers identified more than 550 patients with bipolar disorder, who answered questionnaires about their history of bipolar disorder and childhood trauma. Their DNA was also analyzed, and the researchers found that the effect of childhood trauma on age of onset was mediated by the presence of common genetic variants in proteins related to stress (the serotonin transporter) and immune function (Toll-like receptors). They also found that the traits of mood lability (or moodiness) and impulsivity mediated the effects of trauma on clinical outcomes.
The lasting epigenetic effects of child maltreatment and adversity noted in the above abstract are consistent with a large literature showing more epigenetic effects in these individuals than in controls. While genetics are important, the impact of the environment is also substantial.
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.
