The Addition of Fish Oil to Cognitive Behavioral Case Management is Not Effective for Youth Depression
In a relatively large placebo-controlled study adding a combination of 840 mg of eicosapentaenoic acid (EPA) and 560 mg of docosahexaenoic acid (DHA) versus placebo did not help treat depressed youth undergoing cognitive behavioral case management (CBCM) (Amminger et al, Biol. Psychiatry, June 22, 2023).
These findings add to the ongoing inconsistency of the effectiveness of Omega 3 Fatty Acids in treating depression. It had appeared more effective in younger than older depressed patients, but now even this trend appears unreliable.
A meta analysis does support use Omega 3 Fatty Acids for ADHD, however.
Fish Oil Monotherapy on Depression in Adolescents at High Risk for Bipolar I Disorder: Ambiguity Persists
Researcher Robert K. McNamara and colleagues reported in the Journal of Child and Adolescent Psychopharmacology in a 2020 article that 12 weeks of treatment with omega-3 fatty acids in the form of fish oil did not reduce depression symptoms in adolescents at risk for bipolar disorder when compared to placebo. The primary outcome measured was the results of the Childhood Depression Rating Scale-Revised (CDRS-R).
Fish oil did perform better than placebo on two parts of the rating scale: symptom severity and symptom improvement, especially in weeks 11 and 12 of the study. Omega-3 fatty acids increased creatine and choline in the anterior cingulate, and also increased polyunsaturated fatty acids in red blood cells. The treatment was safe and well-tolerated.
A total of 42 patients between the ages of 9 and 21 who had been diagnosed with depression and had at least one parent with bipolar I disorder received either placebo or 3 fish oil capsules per day. Each capsule contained 450?mg EPA, 40?mg docosapentaenoic acid (DPA), and 260?mg DHA for a total daily dose of 2130?mg EPA + DHA.
Editor’s Note: Ambiguity persists about whether omega-3 fatty acids can improve unipolar or bipolar depression, attention-deficit hyperactivity disorder (ADHD), or prevent the progression of schizophrenia symptoms to the full syndrome. Given the lack of side effects, and the documented effects on red blood cells and brain choline, clinical use of these compounds could be considered in some circumstances.
Meta-Analysis Finds Omega-3 Fatty Acids Do Not Reduce Cardiovascular Disease Risk
In a 2018 meta-analysis published in the journal JAMA Cardiology, researcher Theingi Aung and colleagues found that across 10 studies including a total of 77,197 participants, omega-3 fatty acid supplementation did not reduce risk of coronary heart disease in people at high risk. This newer finding conflicts with a 2017 advisory from the American Heart Association that suggested omega-3 fatty acid supplementation might prevent cardiovascular disease.
When it comes to mood disorders, it has been similarly difficult to pin down whether omega-3 fatty acids are helpful. Data on omega-3 fatty acid supplements for the prevention of depression have been ambiguous, with small numbers of studies and variations in study design that make it difficult to draw strong conclusions about whether these supplements can improve or prevent depression.
A 2016 systematic review by Paola Bozzatello and colleagues in the Journal of Clinical Psychiatry found only seven studies of omega-3 fatty acid supplementation in bipolar disorder. The studies had small sample sizes and widely varying dosage parameters, so the evidence that can be drawn from them is not strong, but the review did find a modest benefit on bipolar depression (but not mania) when omega-3 fatty acids were added to a treatment regimen, compared to treatment as usual.
The same review found that studies of omega-3 fatty acid supplementation in unipolar depression also varied widely, and thus it was difficult to draw inferences from them. Some meta-analyses found no benefit to omega-3 fatty acid supplementation, while others suggested that omega-3s could improve depression. The review found that the type of omega-3 fatty acids used might matter. Supplementation with EPA seemed to improve depression more than supplementation with DHA. The review also cited a 2014 comprehensive meta-analysis by Giuseppe Grosso and colleagues in the journal PLoS One that analyzed the findings from 19 studies in people with depression or depressive symptoms. Grosso and colleagues found that people with more severe depression seemed to benefit more from omega-3s.
Prenatal Prevention of Psychiatric Illness with Nutritional Supplements
In a 2018 article in the American Journal of Psychiatry, researcher Robert Freedman and colleagues shared the results of a systematic review of data on nutritional supplements during pregnancy for the primary prevention of psychiatric illness in the child. Freedman and colleagues concluded that the evidence is robust that prenatal folic acid supplementation plus multivitamins not only can prevent birth defects such as cleft palate, spina bifida, and microcephaly, but also social withdrawal, decreased attention, and aggression at age 18 months. They wrote, “Supplements of up to 4 mg [of folic acid] before 12 weeks gestation have been found to be safe and effective.”
The effects of omega-3 fatty acid supplementation depended on when the supplements were taken. Taking omega-3 fatty acid supplements early in pregnancy was linked to an increase in schizophrenia and more symptoms of attention deficit hyperactivity disorder (ADHD) in the offspring. However, supplementation after 20 weeks of pregnancy decreased preterm delivery, low birth weight, and asthma.
As of 2017, choline supplementation during pregnancy is recommended by the American Medical Association. Their recommendation is based on research in which the choline precursor phosphatidylcholine (5,000-6,300 mg/day) was given to mothers beginning in the 18th week of pregnancy and continued in the newborn for two weeks to three months after birth in the form of 100mg of liquid phosphatidylcholine. This supplementation regimen normalized the P50 auditory evoked potential, a measure of inhibitory sensory gating that is abnormal in patients with schizophrenia and bipolar disorder and infants whose parents had psychosis, depression, or smoked (all risk factors for a later diagnosis of schizophrenia).
Healthy individuals show a reduced response to an auditory cue when it is repeated 50 milliseconds after the initial cue. In people with schizophrenia, response to the repeated cue is not suppressed. Not only did the P50 auditory evoked potential normalize with phosphatidylcholine supplementation, but at 3.5 years of age, those who received phosphatidylcholine supplements in utero and as newborns had fewer problems with attention and social interactions. The findings were even more robust in those with the CHRNA7 genotype (a genetic variation in the alpha 7 nicotinic receptor), which is a risk factor for schizophrenia.
Supplementation with vitamins A and D during gestation also decreased the risk for schizophrenia and autism spectrum disorders in offspring. Recommendations include Vitamin D at doses of 600 to 4,000 IU for pregnant mothers and 400 to 1,000 IU for infants. Because of potential toxicity, vitamin A should be limited to 8,000 units from diet and supplements combined. (Supplements typically contain 2,500 units.)
While there are some methodological limitations to the findings, Freedman and colleagues conclude, “As part of comprehensive maternal and fetal care, prenatal nutrient interventions should be further considered as uniquely effective first steps in decreasing risk for future psychiatric and other illnesses in newborn children.”
Editor’s Note: Given the high risk of psychiatric illness (74%) in the offspring of a parent with bipolar disorder and the finding of abnormal P50 auditory evoked potential in patients with bipolar disorder, the recommended nutritional supplements should be given special consideration during gestation of a child who has a parent with bipolar disorder. According to the 2018 article by Freedman and colleagues, this would include folate, phosphatidylcholine, vitamin A and vitamin D.
Baseline Levels of CRP Could Help Predict Clinical Response to Different Treatments
C-reactive protein (CRP)
C-reactive protein, or CRP, is a marker or inflammation that has been linked to depression and other illnesses. People with high levels of CRP respond differently to medications than people with lower CRP, so assessing CRP levels may help determine which medications are best to treat a given patient.
High baseline levels of CRP (3–5pg/ml) predict a poor response to selective serotonin reuptake inhibitor antidepressants (SSRIs) and to psychotherapy, and are associated with increased risk of recurrent depression, heart attack, and stroke.
However, high baseline CRP predicts a better response to the antidepressants nortriptyline and bupropion. High CRP is also associated with better antidepressant response to infliximab (a monoclonal antibody that inhibits the inflammatory cytokine TNF alpha), while low levels of CRP predict worsening depression upon taking infliximab.
High baseline CRP also predicts good antidepressant response to intravenous ketamine (which works rapidly to improve treatment-resistant depression), minocycline (an anti-inflammatory antibiotic that decreases microglial activation), L-methylfolate (a supplement that can treat folate deficiency), N-acetylcysteine (an antioxidant that can improve depression, pathological habits, and addictions), and omega-3 fatty acids (except in people with low levels of DHA).
High baseline CRP also predicts a good response to the antipsychotic drug lurasidone (marketed under the trade name Latuda) in bipolar depression. In people with high baseline CRP, lurasidone’s positive results have a huge effect size of 0.85, while in people with low CRP (<3pg/ml) the improvement on lurasidone has a smaller effect size (0.35).
In personal communications with this editor (Robert M. Post) in 2018, experts in the field (Charles L. Raison and Vladimir Maletic) agreed that assessing baseline CRP levels in a given patient could help determine optimal strategies to treat their depression and predict the patient’s responsiveness to different treatment approaches.
At a 2018 scientific meeting, researchers Cynthia Shannon, Thomas Weickert, and colleagues reported that high baseline levels of CRP were associated with symptom improvement in patients with schizophrenia when they were treated with the drug canakinumab (marketed under the trade name Ilaris). Canakinumab is a human monoclonal antibody that targets the inflammatory cytokine interleukin-1 beta (Il-1b). Il-1b is elevated in a subgroup of patients with depression, bipolar disorder, or schizophrenia, and CRP levels are an indication of the associated inflammation.
Supplements for the Treatment of Schizophrenia
At the 2018 meeting of the North Carolina Psychiatric Association, researcher Karen Graham reviewed evidence for adjunctive treatments that may help treat schizophrenia when added to antipsychotic medications.
Graham endorsed omega-3-fatty acids, saying that they may delay the conversion to schizophrenia in young people at high risk for the illness. Data in chronic schizophrenia are more equivocal.
Data on the effects of vitamin D3 in schizophrenia are mixed, but D3 is often low in patients with psychotic disorders, and supplementation with vitamin D3 in the general population has been associated with decreases in cancer and all-cause mortality.
Graham indicated that in three studies vitamin B6 (pyridoxine) decreased tardive dyskinesia, a side effect of antipsychotic medication that is characterized by repetitive or jerky involuntary movements of the face and body. B6 also reduced the severity of akathisia or restless legs, which is comparable to the effects of 40mg/day of the beta blocker drug propranolol. Graham recommended a dose of 300mg/day of B6 that could be increased up to 600mg twice per day. The onset of effects usually begins by week three, and the cost ranges from 25 to 80 cents per day.
The antioxidant supplement N-acetylcysteine (NAC) may also help. Graham described six studies that found NAC had positive effects on negative symptoms (apathy, blunted emotions, etc.) and/or cognition in patients with schizophrenia. The dosage in these studies was usually 2 grams/day for 24 weeks. The cost was 50 cents per day.
Two 8-week trials of L-theanine (an amino acid found in green and black tea) at doses of 400mg/day improved negative symptoms and anxiety in 40 patients with schizophrenia. The rationale for the study was that L-theanine increases inhibitory neurotransmitters, modulates the amino acid 5-HTP and the neurotransmitter dopamine, increases brain-derived neurotrophic factor (BDNF), and may be neuroprotective after a heart attack or a traumatic brain injury. The cost is 40 cents per day.
Graham reported that the supplement ginkgo biloba produced significant improvement in negative symptoms and total symptoms in eight clinical trials that included a total of 1,033 patients with schizophrenia. Doses ranged from 240 to 360 mg/day. These supplements (usually extracted from leaves of the ginkgo tree) have not been found to have many side effects, but they can reportedly increase post-operative bleeding. Gingko biloba supplements cost 20 to 80 cents per day. There is also at least one positive study of ginkgo biloba in tardive dyskinesia.
Three of four studies of cannabidiol in schizophrenia have been positive (at doses of 600, 800, and 1,000 mg/day in studies that lasted four to six weeks). There are now six additional ongoing studies listed on the website clinicaltrials.gov. There is little of this diol component in regular marijuana, and the cost of pure cannabidiol is unfortunately an exorbitant $60 to $100/day.
There is a positive controlled study of the herb ashwagandha in 66 patients with schizophrenia.
Not included in Dr. Graham’s review was the prenatal treatment of women with phosphatidylcholine (900mg/day) followed by supplements in the newborn, which normalized an aspect of sensory gating known as P50 in patients with schizophrenia. Healthy individuals show a reduced response to an auditory cue when it is repeated 50 milliseconds after the initial cue. In people with schizophrenia, response to the repeated cue is not suppressed. This has been suggested by researchers Robert Freedman and Randal G. Ross in a 2015 article in the Shanghai Archives of Psychiatry as a possible primary preventive approach to schizophrenia.
Pregnant women in their second and third trimesters should at least consume foods high in choline, especially if the fetus is at high risk for schizophrenia because of a family history of schizophrenia.
Beef liver is very high in choline, providing 420mg per slice. Other animal products provide significant choline, such as eggs (120 mg/egg), beef (90mg/100g), chicken liver (85mg/liver), fish (85mg/100g), bacon (35mg/strip) or other pork, chicken (67mg/100g). Tofu (36mg/half cup) and cereal (22mg/half cup) are also sources of choline.
Foods High in Choline
| Beef liver | 1 slice | 420mg choline; |
| Egg | 1 egg | 120; |
| Beef | 100 gm | 90; |
| Chicken liver | 1 liver | 85; |
| Fish | 100 gm | 85; |
| Bacon or pork | 2 strips bacon | 70; |
| Chicken | 100 gm | 67; |
| Tofu | 120 ml (0.5 cup) | 36; |
| Cereal | 120 ml (0.5 cup) | 22 |
Omega-3 Fatty Acids Improve Executive Function in Youth with Mood Disorders
A 2017 study by Anthony T. Vesco and colleagues in The Journal of Child Psychology and Psychiatry suggests that in youth with depression or bipolar not otherwise specified (BP-NOS), omega-3 fatty acid supplements improve executive functioning and behavior regulation compared to placebo.
Ninety-five participants aged 7–14 years received two capsules daily of either omega-3 fatty acids (1.87g total per day, mostly consisting of EPA) or placebo for 12 weeks. Those who received omega-3s showed improvement in executive functioning (which can include planning and decision-making), behavioral regulation, and metacognition, as rated by their parents.
Editor’s Note: Since omega-3 fatty acids have no known side effects, there is little reason not to try them in youth with depression or bipolar disorder.
Omega-3 Fatty Acids Improve ADHD
A 2017 systematic review and meta-analysis found that omega-3 fatty acid supplementation improves symptoms of attention-deficit hyperactivity disorder (ADHD) in children and adolescents. The article by Jane Pei-Chen Chang and colleagues in the journal Neuropsychopharmacology identified seven randomized controlled trials in which omega-3 fatty acids improved clinical symptoms of ADHD, and three trials in which omega-3s improved cognitive measures associated with attention.
The meta-analysis also found that children and adolescents with ADHD have lower than normal levels of the omega-3s DHA and EPA, in addition to lower total levels of omega-3s measured in blood and cheek tissues.
Chang and colleagues suggest that omega-3 fatty acid supplementation is a potentially helpful and largely risk-free treatment option for ADHD in children and adolescents.
Omega-3 Fatty Acids May Be Helpful Early in Schizophrenia, But Not Later
Some studies have suggested that omega-3 fatty acids may be helpful in the treatment of schizophrenia, but data to support this idea have been inconsistent. A recent meta-analysis of research on omega-3s and schizophrenia suggests that this nutritional supplement might be more useful in early-stage schizophrenia than in later illness.
At the 2016 meeting of the Society of Biological Psychiatry, researchers led by Alexander T. Chen presented the findings of their meta-analysis. First they analyzed six studies that shared a common scale for measuring schizophrenia symptoms. In these studies, omega-3 fatty acids did not outperform placebo when used as an add-on treatment to antipsychotics for people with schizophrenia.
In four remaining studies of omega-3 fatty acids and schizophrenia, the omega-3s were associated with improvement only in patients in the early stages of schizophrenia. Compared to placebo, the supplements decreased non-psychotic symptoms, decreased the dosage of antipsychotic medication patients required, and improved early treatment response (but not late treatment response) in patients in their first episode of schizophrenia.
In the same study, omega-3 fatty acids also reduced conversion to full-blown schizophrenia and psychotic symptom severity in patients at high risk for schizophrenia who were having preliminary symptoms of the illness.
Editor’s Note: Researcher Paul E. Keck has also found that omega-3 fatty acids may be more effective early in bipolar disorder rather than later. He reported that younger patients with bipolar depression and rapid cycling showed more improvement when taking the omega-3 fatty acid EPA than when taking placebo. In contrast, patients with bipolar depression who were over the age of 45 did worse on EPA than on placebo.
Part of the ambiguity about whether omega-3 fatty acids can help treat or prevent mental illness may be explained by the supplements working better in younger people or earlier in the course of an illness.
Meta-Analysis Shows Anti-Inflammatory Treatments Improve Bipolar Depression
It has been clear for some time that depression and inflammation are linked. This has led researchers to explore a variety of anti-inflammatory agents to treat depression. A meta-analysis of studies examining anti-inflammatory treatments for bipolar depression was published in the journal Bipolar Disorders in 2016.
Researcher Joshua D. Rosenblat and colleagues identified eight randomized controlled trials that met their criteria for anti-inflammatory treatments of bipolar disorder. These treatments included nonsteroidal anti-inflammatory drugs (NSAIDs such as ibuprofen and aspirin), omega-3 fatty acids, the antioxidant N-acetylcysteine, and pioglitazone (used to treat diabetes). Overall, the anti-inflammatory treatments had a moderate and statistically significant antidepressant effects. No serious side effects were reported, and the anti-inflammatory treatments did not cause a switch into mania in any of the participants.
The diversity of the anti-inflammatory treatments reviewed in this meta-analysis limit the extent to which it can be interpreted, but it is clear that more research on anti-inflammatory treatments for bipolar depression is needed. An open question is whether patients with particularly elevated levels of inflammatory markers in their blood would respond better to these anti-inflammatory treatments.
