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.
Differences in Depressive Episodes Across Bipolar I, II, and Major Depression
In a recent retrospective study, people with bipolar disorder I, bipolar disorder II, and major depressive disorder were interviewed about a 14-year period of their illness, and several differences emerged.
People with bipolar disorder I described their illnesses as including more psychomotor retardation (slowing of movements) and more psychotic features. People with bipolar disorder II had more mixed states than both people with major depression and people with bipolar I disorder. They also had less psychomotor slowing than people with bipolar I disorder.
Another purpose of this study by Andrew Frankland and colleagues in the Journal of Clinical Psychiatry, was to determine the effectiveness of the Probabalistic Approach to Bipolar Disorder, a statistical method for differentiating diagnoses. The approach was successful in differentiating both bipolar subtypes from major depression, but not in differentiating between the bipolar subtypes.
