Inflammation has been linked to mood disorders. A 2016 meta-analysis in the journal Lancet Psychiatry described the role of inflammatory marker C-reactive protein (CRP) in bipolar episodes. Researchers led by Brisa S. Fernandes identified 27 studies that measured CRP levels in a total of 2,161 patients with bipolar disorder and 81,932 healthy participants. The researchers determined that compared to healthy controls, people with bipolar disorder have higher levels of CRP. CRP levels were moderately elevated between episodes and during depression, and substantially elevated during episodes of mania.
Editor’s Note: This meta-analysis shows that CRP is linked to bipolar disorder, and the inflammatory burden is highest during mania. It remains to be seen whether anti-inflammatory treatments work best in patients with high CRP levels compared to normal CRP levels.
CRP is also a risk factor for cardiovascular disease, and lithium and other treatments for bipolar disorder probably lower CRP levels.
The same group of researchers previously showed that statins, drugs typically used to lower cholesterol, could help alleviate depression. Since statins have anti-inflammatory effects, they can probably reduce depression risk in addition to lowering cardiovascular risk, as initial studies suggest.
Other drugs with anti-inflammatory effects that may improve depression include the anti-arthritis drug celecoxib and the antibiotic minocycline. The amino acid N-acetylcysteine and omega-3 fatty acids also have anti-inflammatory effects and have been found to improve depression in some studies.
Evidence from multiple studies has indicated the importance of beginning preventative treatment, particularly with lithium, early in the course of bipolar disorder. A 2016 comprehensive literature review by researcher Katie Joyce and colleagues in the International Journal of Bipolar Disorders concluded that psychoeducation and medication are more effective in bipolar disorder when applied in earlier stages of the illness rather than later stages.
Several studies suggest that treatment for bipolar disorder should be started specifically after the first manic episode.
A 2014 study by researcher Lars Kessing and colleagues in the British Journal of Psychiatry examined 4,700 patients treated with lithium in Denmark. Kessing and colleagues found that those who started treatment after one manic episode were less likely to find lithium ineffective than those who started later.
Another study by researcher Michael Berk and colleagues presented at the International Society for Bipolar Disorders found that after a first manic episode, a year of treatment with lithium was much more effective on all measures of outcome, including mania and depression ratings, brain imaging, and neuropsychological functioning, than a year when patients were randomized to quetiapine (Seroquel).
Researcher Lakshmi Yatham and colleagues presented research at the International Society for Bipolar Disorders showing that patients recovered from the neuropsychological deficits associated with a first episode of mania if they were well treated and had no further episodes, while those who had new episodes did not return to their baseline capabilities. This suggests that early treatment that prevents future episodes helps maintain a healthy brain.
Kessing and colleagues previously reported in the British Journal of Psychiatry in 2013 that patients randomized to two years of treatment in an outpatient clinic specializing in mood disorders following a first hospitalization for mania had 40% fewer recurrences of bipolar episodes over the next six years than those who received treatment as usual. These data indicate that early treatment, which may include psychotherapy, medications, mood charting (i.e. keeping a daily record of symptoms) and illness education, can improve the long-term course of illness. Lithium is often a key component of such treatment.
Editor’s Note: This type of intensive, ongoing treatment is not the norm after a first manic hospitalization in the United States, but it should be. Given the new data on the impact of starting lithium after a first episode of mania, and lithium’s superiority over quetiapine in the year following a first episode, lithium treatment should be standard following a diagnosis of bipolar disorder.
In the past, sometimes doctors have recommended waiting until a patient has had multiple episodes of mania before beginning preventative treatment with lithium. This now appears to be a mistake.
Lithium protects against depressive as well as manic recurrences, and there is also evidence that it increases hippocampal and cortical volume, helping prevent cognitive deterioration in those with mild cognitive impairment. Lithium is also the most effective mood stabilizer for preventing suicide, and it increases the length of telomeres (caps on the end of DNA strands), thus preventing a wide range of medical and psychiatric illnesses. Lithium may need to be combined with other drugs to achieve a complete remission, but using it after a first mania is a good place to start.
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.