White Matter Abnormalities in the Brain Predict Onset of Psychosis

February 6, 2013 · Posted in Brain Imaging · Comment 

brainAt the 2012 meeting of the American Academy of Child and Adolescent Psychiatry (AACAP), Carrie E. Bearden presented data from a study that predicted conversion to psychosis in at-risk youth (those who have prodromal symptoms or a particular genetic mutation that leads to psychosis) by observing white matter abnormalities.

Bearden found that the degree of white matter abnormality seen during magnetic resonance imaging (MRI) was proportional to the degree of cognitive deficit in patients who subsequently developed a first episode of psychosis. The white matter abnormalities were seen particularly in the superior longitudinal fasciculus (SLF) and were associated with increased severity of symptomatology. The overall degree of white matter alteration was also significantly related to clinical outcome 15 months later.

Editor’s Note: The SLF is a major neuronal conduit between prefrontal cortical systems, which are responsible for cognition and planning, and the parietal cortex, which is responsible for spatial abilities. Disruption of this fiber track has been related to difficulties in social cognition and “theory of mind” concepts, like inferring what others might be thinking.

Psychosis Risks with Marijuana Use

April 11, 2012 · Posted in Risk Factors · Comment 

marijuanaAt a recent conference Robin Murray, a researcher based in London, gave a talk about the potential adverse effects of tetrahydrocanabinol (THC). Considerable data indicate that chronic long-term smoking of marijuana is associated with the doubling of the risk of psychosis. Moreover, if a marijuana user has a common genetic variant in the catechol-o-methyltransferase enzyme (COMT), they are at substantially increased risk for the development of psychosis. New data also indicate that frequent use of marijuana can also be associated with an earlier onset of schizophrenic psychosis than would ordinarily occur without the substance use. Data also suggest that the psychosis associated with THC use is more difficult to treat than that without such use.

Murray also reported on a new risk that is associated with more potent new products. Older, natural forms of marijuana contained a compound called cannabidiol, which is associated with calming effects and possible antipsychotic effects. In a new synthetic preparation of THC called skank or spice, there is a higher amount of THC, but none of the positive diol compound. Thus there are some important caveats to the prevailing view that marijuana is relatively harmless.

Editor’s Note: Marijuana use brings a clear-cut increased risk for psychosis, which appears to interact with a common gene polymorphism and which is increased with use of a new synthetic preparation called skank or spice.  If a marijuana user has a concurrent mood disorder, the risks appear to be even greater.  The one sure pharmacological effect of marijuana is an amotivational syndrome, and motivational deficits are one of the core components of depression.

Given the difficulty of treating the mood and schizophrenic disorders, a patient should not risk worsening their illness with marijuana.  N-acetylcysteine is one treatment option that may bring about decreased craving for and avoidance of marijuana and a number of other abused substances, as well as being helpful for mood and negative symptoms in schizophrenia.

The Evolving Omega-3 Fatty Acid Story: The Icing on the Cake (And Why It Shouldn’t Be Eaten)

October 3, 2011 · Posted in Current Treatments · Comment 

sources of omega-3 fatty acidsOmega-3 fatty acids are important for brain development and function and are essential to the human diet since they cannot be synthesized by the body. Omega-3 fatty acids are derived from canola oil, walnuts, flax seed oil, leafy vegetables, and especially fish. The main omega-3 fatty acids include eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). They have anti-inflammatory effects, unlike omega-6 fatty acids, which are pro-inflammatory. The omega-6 fatty acids come from soy, peanuts, corn oil, and meats, and are associated with increases in obesity, myocardial infarction, and stroke.

In a recent review of the literature, John Davis and Joe Hiblen found that diets that include high levels of omega-3 fatty acids are associated with decreased incidence of depression, suicide, and cardiovascular disease. The researchers performed a meta-analysis of all the prospective depression treatment studies of omega-3 fatty acids compared to placebo. They found that EPA had antidepressant effects in humans, with moderate effect size and a high degree of statistical significance. DHA, however, did not appear to have an antidepressant effect, and pure DHA was even associated with some worsening of depression.

Editor’s note: This meta-analysis helps clarify some of the ambiguities in the literature about the antidepressant efficacy of the omega-3 fatty acids, clarifying that EPA alone is an effective antidepressant. The one study that did not find antidepressant effects with EPA was carried out by the Bipolar Collaborative Network, in which I am an investigator. Our study, published in an article by Keck et al., showed that 6g of EPA was not significantly more effective than placebo in bipolar depression or in rapid cyclers. However, there is some indication that 6g may be too high a dose of EPA, and most of the recommendations now suggest using 1-2g of either EPA or an EPA/DHA combination. Read more

Treatment Guidelines for Two Hypothetical Cases in Children

There are no FDA-approved treatments for children under age 10 with bipolar disorder. For an article in Psychiatric Annals, this editor and Janet Wozniak asked experts how they would sequence treatment of a hypothetical case of a 6-year-old with extreme mood instability consistent with a diagnosis of BP -NOS (see Table I). We also asked how the experts would treat a different case of a 9-year-old with a full-blown psychotic BP-I mania (see Table II).

Table 1

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Table 2

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The results are presented  and discussed in detail in the article, and are presented here to reinforce several points. The recommendations for children under 10 and for BP NOS are highly similar to consensus guidelines for older BP I children compiled by Kowatch et al.

Treatments in the face of non-response to option A or others are sequenced differently by different experts, but almost always involve an atypical antipsychotic (AA) or a mood stabilizer (MS) such as lithium, valproate, carbamazepine/oxcarbazepine, or rarely, lamotrigine. Revisions of atypical antipsychotics and mood stabilizers and use of combinations are the common next strategies.