Patients with bipolar disorder often show increases in signs of inflammation, including levels of the proteins IL-2, IL-4, Il-6, IL-10 and tumor necrosis factor in their blood. Lithium is the most effective treatment for bipolar disorder, but it is not yet clear how it works. A recent study by researcher Joao de Quevado and colleagues determined that lithium can reduce the same inflammatory markers in rats.
Rats were treated with amphetamine to induce mania-like behavior, which was accompanied by increases in some of the same inflammatory markers in the blood and brain that are increased in people with bipolar disorder. Lithium treatment reduced both the manic behavior and levels of these inflammatory proteins in the rats.
The researchers concluded that lithium may treat mania by reducing inflammation.
Researchers are looking for better ways of predicting whether children at risk for bipolar disorder will go on to develop the illness. A 2015 study by David Axelson and colleagues in the American Journal of Psychiatry reported that in the offspring of parents with bipolar disorder, diagnoses of sub-threshold mania, depression, and disruptive behavior disorders were associated with subsequent diagnosis of full-blown Bipolar I or Bipolar II disorders six to seven years later.
More recently, in an article by Danella M. Hafeman and colleagues in the American Journal of Psychiatry, the same group of investigators has examined how symptoms (rather than categorical diagnoses, as in the earlier study) predict the development of bipolar disorder. In children and adolescents at high risk for bipolar disorder (because they have a parent with the disorder) three types of symptoms were the best predictors of later bipolar disorder: anxiety/depression at the time participants entered the study, unstable mood or irritability both when entering the study and shortly before a bipolar diagnosis, and low-level manic symptoms observed shortly before diagnosis.
The earlier the age at which a parent was diagnosed with a mood disorder, the greater the risk that the offspring would also be diagnosed with bipolar disorder. Youth with all four risk factors (anxiety or depression, mood changes, low-level mania, and a parent who was diagnosed with a mood disorder at an early age) had a 49 percent chance of developing bipolar disorder, compared to a 2 percent chance among those without those risk factors.
Childhood onset of bipolar disorder and long delays until first treatment for depression or mania are both significant predictors of a poor outcome in adulthood compared to adult onsets and shorter delays to treatment. Read more
Vitamin D3 tends to be low in children and adolescents with mania, but supplements may help. In a small open study published in the Journal of Child and Adolescent Psychopharmacology in 2015, Elif M. Sikoglu and colleagues administered 2000 IU of vitamin D3 per day to youth aged 6–17 for eight weeks. Sixteen of the participants had bipolar spectrum disorders (including subthreshold symptoms) and were exhibiting symptoms of mania. Nineteen participants were typically developing youth.
At the beginning of the study, the youth with bipolar spectrum disorders had lower levels of the neurotransmitter GABA in the anterior cingulate cortex than did the typically developing youth. Following the eight weeks of vitamin D3 supplementation, mania and depression symptoms both decreased in the youth with bipolar spectrum disorders, and GABA in the anterior cingulate cortex increased in these participants.
Editor’s Note: GABA dysfunction has been implicated in the manic phase of bipolar disorder. While larger controlled studies of vitamin D supplementation are needed, given the high incidence of vitamin D deficiency in youth in the US, testing and treating these deficiencies is important, especially among kids with symptoms of bipolar illness.
Lithium is the treatment of choice for adults with bipolar disorder, but has rarely been studied in children or adolescents. One of the first double-blind placebo-controlled trials of lithium for the treatment of mania in children and teens aged 7–17 showed that the drug produced greater improvement in mania than did placebo. Side effects included blurred vision, abdominal pain, diarrhea, nausea, vomiting, fatigue, thirst, increased thyroid-stimulating hormone, decreased appetite, dizziness, sedation, tremor, increased urination, and rash.
In the study by researcher Adelaide S. Robb and colleagues, which was presented at the 2015 meeting of the American Academy of Child and Adolescent Psychiatry, doses began at 300mg twice a day, were based on each child’s weight, and were slowly increased.
At the same meeting, researcher Russell Scheffer presented data on 41 children who continued lithium treatment for 16 weeks with good results. The mean dose was 27.8 +/- 6.7 mg/kg per day.
In late 2015, the Food and Drug Administration approved the new atypical antipsychotic drug cariprazine for the treatment of schizophrenia and mania in adults. The approval followed a series of clinical trials that showed that the drug reduced symptoms of each illness compared to placebo.
The most common side effects of cariprazine reported in the trials included tremor, slurred speech, and involuntary muscle movements.
The first large, randomized, double-blind study of lithium in children and teens has shown that as in adults, the drug can reduce mania with minimal side effects. The study by researcher Robert Findling was published in the journal Pediatrics in October. Lithium is the best available treatment for adults, but until now little research had been done on treatments for children and teens with bipolar disorder.
In the study, 81 participants between the ages of 7 and 17 with a diagnosis of bipolar I disorder and manic or mixed episodes were randomized to receive either lithium or placebo for a period of eight weeks. By the end of the study, those patients taking lithium showed greater reductions in manic symptoms than those taking placebo. Among those taking lithium, 47% scored “much improved” or “very much improved” on a scale of symptom severity, compared to 21% of those taking placebo.
Dosing began at 900mg/day for most participants. (Those weighing less than 65 lbs. were started at 600mg/day.) Dosing could be gradually increased. The mean dose for patients aged 7–11 was 1292mg/day, and for patients aged 12–17 it was 1716mg/day.
Side effects were minimal. There were no significant differences in weight gain between the two groups. Those taking lithium had significantly higher levels of thyrotropin, a peptide that regulates thyroid hormones, than those taking placebo. If thyroid function is affected in people taking lithium, the lithium dosage may be decreased, or patients may be prescribed thyroid hormone.
The atypical antipsychotic asenapine has been reformulated for bipolar I disorder in children aged 10–17. The drug (trade name Saphris) was approved by the Food and Drug Administration (FDA) in 2009 for adults with schizophrenia and bipolar disorder. It is sometimes used as a treatment for mixed episodes (depression with some symptoms of mania).
The new formulation consists of 2.5mg tablets that are taken sublingually (under the tongue), and are available in a black cherry flavor. These can be prescribed as monotherapy for the acute treatment of manic or mixed episodes in children and teens.
Mice with a particular genetic mutation affecting circadian rhythms exhibit symptoms that resemble those of human mania: disruption of sleep and wake cycles, hyperactivity, and reduced anxiety and depression. It has been found that these behaviors can be normalized by inhibiting a type of enzyme called histone deacetylases (HDACs). HDACs bring about epigenetic changes to gene transcription by removing acetyl groups from histones, the structures around which DNA is wrapped. Removal of the acetyl group tightens the structure of the DNA, making it more difficult to transcribe. The drug valproate (trade name Depakote) is one type of HDAC inhibitor. It prevents the removal of the acetyl groups, loosening the structure of the DNA, making it easier to transcribe.
A recent study by Ryan Logan and colleagues compared the effects of valproate and other HDAC inhibitors on mice with a mutation in the Clock delta 19 gene, which causes mania-like symptoms. Valproate and the HDAC inhibitor SAHA both normalized the mice behavior. MS275, another HDAC inhibitor that targets only class I HDACs, also normalized the behaviors. The researchers were able to determine that all of these treatments targeted a specific class I HDAC called HDAC2, which has been implicated in schizoaffective and bipolar disorders.
These data link epigenetic mechanisms (HDAC inhibition) to the antimanic effects of valproate in this animal model of mania. It appears that maintaining the presence of acetyl groups on histones has antimanic effects in mice with a mutation in the Clock delta 19 gene.
There is a large body of research showing that lithium is better than placebo and a variety of comparison drugs at preventing manic episodes in people with bipolar disorder. It has been less clear whether lithium is as effective in preventing depressions in bipolar patients. In a 2014 meta-analysis in the International Journal of Bipolar Disorders, Emanuel Severus and colleagues confirmed that lithium was more effective than placebo at preventing mood episodes overall and manic episodes. In a fixed effect statistical analysis, lithium was also better at preventing depressive episodes.
The portion of the meta-analysis comparing lithium to placebo included seven randomized controlled trials that included a total of 1,580 patients. Lithium was more likely than placebo to lead to patients dropping out of a study for reasons other than a mood episode, but patients who received lithium were more likely to complete their clinical trials.
Another part of the meta-analysis compared lithium to anticonvulsant drugs. Seven trials were included totaling 1,305 patients. Lithium was better than anticonvulsants at preventing manic episodes, but equally effective at preventing mood episodes overall and depressive episodes specifically. There was also no difference in patients dropping out of the trials or completing the trials.
The researchers concluded that lithium remains the most valuable treatment option for bipolar disorder, because no other drug has such consistent efficacy in preventing manias and depressions and mood episodes in general.
At the 2014 meeting of the American Academy of Child and Adolescent Psychiatry, researcher Adelaine Robb reported that in 81 children with mania (aged 7-17), lithium was superior to placebo in reducing the severity of mania measured on the Young Mania Rating Scale. There had been some debate about the efficacy of lithium in young children with mania, but this study clearly indicates lithium’s effectiveness. The drug is approved by the Federal Drug Administration (FDA) for use in patients with bipolar disorder aged 12 and up.
Another researcher, Vivian Kafrantaris, found that in children who averaged 14.5 years of age, lithium increased the volume of the corpus callosum, a bundle of neural fibers that connects the brain’s right and left hemispheres. Lithium also normalized white matter integrity in other neural fiber tracts—the cingulum bundle and the superior longitudinal fasciculus. The authors concluded that lithium may “facilitate microstructural remodeling of white matter tracts involved in emotional regulation.”
Editor’s Note: There is much research showing that in adults, lithium has positive effects on the brain, including increases in hippocampal and cortical grey matter volume. Now it appears that lithium can improve white matter integrity in the developing brain as well.