One Hit of THC Tied to Psychotic Symptoms in Adults with No History of Mental Illness
In a meta-analysis published in the journal Lancet Psychiatry, researcher Guy Hindley and colleagues reported that in otherwise healthy adults, a single dose of THC (equivalent to smoking one joint) produced transient psychotic symptoms.
The meta-analysis included 9 studies with a total of 196 participants. The researchers included studies in which participants took tetrahydrocannabinol (THC, the psychoactive component in marijuana) or placebo, and psychotic symptoms were measured.
The researchers also sought out studies in which cannabidiol or CBD was given in combination with THC, but there were not enough of these to derive significant results. CBD does not produce schizophrenia-like symptoms on its own, and some think it may have anti-psychotic effects, but findings on this topic have been mixed.
Taking THC had a large effect size on total psychotic symptoms and negative symptom severity (such as emotional flatness or avolition). It also had an effect on positive symptom severity (for example, hallucinations or delusions). The effects were larger with intravenous administration than with inhaled administration, and tobacco smokers had less severe positive symptoms.
Of four studies that included CBD, only one found that CBD reduced THC-induced psychotic symptoms.
Editor’s Note: Longer-term use of marijuana in adolescents and young adults doubles the risk of psychosis, and other data suggest that chronic use of marijuana at high doses can be associated with new onset of a diagnosis of bipolar disorder or schizophrenia. As cannabis products are being decriminalized around the US, it is worth noting some of the risks of marijuana use, particularly marijuana with a high level of THC.
Predicting Onset of Bipolar Disorder in Children at High Risk: Part I
At the 2019 meeting of the American Academy of Child and Adolescent Psychiatry, one symposium was devoted to new research on predicting onset of bipolar disorder in children who have a family history of the disorder. Below are some of the findings that were reported.
Symptom Progression
In offspring of parents with bipolar disorder, researcher Anne Cecilia Duffy found that symptoms in the children tended to progress in a typical sequence. Childhood sleep and anxiety disorders were first to appear, then depressive symptoms, then bipolar disorder.
Different Types of Illness May Respond Best to Different Medications
Duffy’s research also suggested links between illness features and a good response to specific medications. Those offspring who developed a psychotic spectrum disorder responded best to atypical antipsychotic medication. Those with classical episodic bipolar I disorder responded well to lithium, especially if there was a family history of lithium responsiveness. Those offspring with bipolar II (and anxiety and substance abuse) responded well to anticonvulsant medications.
If parents with bipolar disorder had experienced early onset of their illness, their children were more likely to receive a diagnosis of bipolar disorder.
The offspring of lithium-responsive parents tended to be gifted students, while those from lithium non-responders tended to be poorer students.
Comparing Risk Factors for Bipolar Disorder and Unipolar Depression
Researcher Martin Preisig and colleagues also showed that parental early onset of bipolar disorder (before age 21) was a risk factor for the offspring receiving a diagnosis of bipolar disorder. Parental oppositional defiant disorder (ODD) was also a risk factor for bipolar disorder in the offspring. The emergence of depression, conduct disorder, drug use, and sub-syndromal hypomanic symptoms also predicted the onset of mania during childhood.
Conversely, sexual abuse and witnessing violence were strong risk factors associated with a diagnosis of major (unipolar) depressive disorder. Being female and experiencing separation anxiety were also factors that predicted unipolar depression.
Predicting Conversion to Mania
Researcher Danella M. Hafeman reported that mood swings (referred to in the literature as “affective lability”), depression/anxiety, and having a parent who had an early onset of bipolar disorder were linked to later diagnoses of mania. Immediate risk factors that predicted an imminent onset of mania included affective lability, substance abuse, and the presence of sub-threshold manic symptoms.
Cannabis May Produce More Brain Changes in Teens with Bipolar Disorder than in Healthy Teens
At the 2019 meeting of the International Society for Bipolar Disorders, researcher Benjamin Goldstein of Sunnybrook Research Institute in Toronto reported that adolescents with bipolar disorder who smoked marijuana had greater deficits in certain brain areas than did adolescents who did not have bipolar disorder. The areas affected included the dorsal lateral and rostral middle frontal cortex, and middle cortex. Goldstein concluded, “Adolescents with [bipolar disorder] may be particularly sensitive to the neurostructural effects of cannabis.”
Marijuana in general causes adverse changes in brain structure and cognition and vulnerability to paranoia and psychosis. Heavy use in adolescence is associated with an increased incidence of the onset of bipolar disorder and schizophrenia. The Goldstein data suggest several possible causal mechanisms. Those with bipolar disorder may already have brain abnormalities that are exacerbated by marijuana use. Alternatively, marijuana and bipolar disorder together may impact brain structure more than either factor alone would.
Alcohol Use Disorders That Begin Before Age 21 May Cause Lasting Changes to Amygdala
In a 2019 article in the journal Translational Psychiatry, researcher John Peyton Bohnsack and colleagues report that people with alcohol use disorders that began before they were 21 years of age show amygdala changes that people with alcohol use disorders that began after the age of 21 do not appear to have.
The amygdalas of those who began abusing alcohol in adolescence showed greater expression of the long non-coding RNA known as BDNF-AS. The increased BDNF-AS was associated with decreased levels of brain-derived neurotrophic factor (BDNF) in the amygdala. BDNF protects neurons and is important for learning and memory.
According to Bohnsack and colleagues, “Adolescence is a critical period in brain development and adolescent drinking decreases orbitofrontal cortex activity and increases amygdala activity leading to less executive control, more emotional impulsivity, alterations in decision-making, and [a higher risk of engaging] in risky behaviors and develop[ing] mental health problems later in life.”
Psychiatric Risks in Offspring of Parents with Bipolar/Unipolar Disorders
At the 2019 meeting of the International Society for Bipolar Disorders, researcher Martin Preisig and colleagues from Lausanne, Switzerland reported on a longitudinal study of mood disorders in offspring of parents with bipolar disorder, unipolar depression, or no history of psychiatric illness. The study included 446 children (with an average age of 10.1 years at the beginning of the study), who participated for an average of 11.9 years.
Preisig and colleagues determined symptoms and other factors that preceded psychiatric illness. They found that bipolar disorder in the offspring was preceded by sub-threshold hypomania, major depression, and conduct disorder. Bipolar disorder in the offspring was also predicted by parental early-onset bipolar disorder.
Major depression was preceded by separation anxiety disorder, and witnessing violence or being a victim of sexual abuse.
Preisig and colleagues concluded that not only did bipolar disorder and major depressive disorder have different familial origins, they also had different antecedents and risk factors.
Inflammation Associated with Cognitive Deficits
At the 2019 meeting of the International Society for Bipolar Disorders, researcher Katherine E. Burdick and colleagues at Brigham and Women’s Hospital and Harvard Medical School reported that in 240 patients with bipolar disorder who were not currently having a manic or depressive episode, markers of inflammation were associated with cognitive deficits.
Inflammation was associated with cognitive deficits in general, and there were also some relationships between specific inflammatory markers and types of cognitive processing. They found that the inflammatory markers TNF-alpha, TNFR1, and TNFR2 influenced cognitive flexibility. The inflammatory marker VEGF influenced reward processing, while IL-6/IL-6r influenced spatial processing. IL-1beta and IL-1RA influenced social cognition.
Burdick and colleagues found it was important to include both primary and secondary mediators of inflammation in their research “as the effects of the primary pro-inflammatory cytokines can be blocked by a number of decoy receptors and soluble antagonists.” Elevations in these can provide additional information about the function of the immune system.
Editor’s Note: Targeting inflammation with the anti-inflammatory treatments minocycline and celecoxib has been shown to improve depression. Now the role of anti-inflammatory drugs in improving cognition deserves further attention.
Mounting Evidence of Mitochondrial Dysfunction in Bipolar Disorder
mitochondrion
At the 2019 meeting of the International Society for Bipolar Disorders, researchers Ana Andreazza, Olivia Dean and colleagues reviewed substantial data that implicate mitochondrial dysfunction in the mood and energy fluctuations that make up bipolar disorder. Most of the neurobiological alterations known to occur in bipolar disorder have a relationship to mitochondria, which produce energy within cells. These alterations include abnormalities in glutamate, gene expression, apoptosis (cell death), oxidative stress, low ATP (a molecule that stores energy), altered ion pumps, increased intracellular calcium, and insufficient glutathionine (an antioxidant made up of three amino acids).
Coenzyme Q10 is a mitochrondrial enhancer of Complex I, an enzyme that is key to the first step in mitochondrial energy production. A 2018 controlled study by Maryam Mehrpooya and colleagues published in the Journal of Clinical Psychopharmacology found that 200mg/day of CoQ10 was more effective than placebo at reducing symptoms of bipolar depression when added to patients’ stable treatment regimens that included mood stabilizers and antidepressants. The effect size was large (0.87), and it took eight weeks for the benefit over placebo to appear. Response rate to CoQ10 was 72% compared to 12% to placebo.
Editor’s Note: Some formulations of CoQ10 do not cross the blood-brain barrier easily, so only a very small percentage of the CoQ10 gets into the brain. Thus, consumers should be careful about the type of product they purchase. The one made by Takeda Pharmaceutical Company is likely to be effective.
Early Predictors of Suicide and Lithium as an Anti-Suicide Drug
At the 2019 meeting of the International Society for Bipolar Disorders, researcher Gin S. Malhi discussed early predictors of suicide in people with bipolar disorder, such as younger age of illness onset, early life stressors, and family history of suicide. Impulsivity, hopelessness, cognitive deficits and substance use are risk factors, both for suicide in general and for an imminent suicide attempt. Proximal risk factors that indicate someone may make a suicide attempt soon include: mood swings, rapid cycling, increased depression, hospitalization, and severe anxiety.
Editor’s Note: Among all psychotropic drugs, lithium has the best data supporting its anti-suicide effects, both at therapeutic doses in patients with bipolar disorder and at trace levels in the water supply in the general population. People who live in locations where more lithium is naturally present in the water supply have lower rates of suicide than those who live in places with less lithium in the water. Malhi also noted that the antioxidant N-acetylcysteine (NAC), which has positive effects on mood and habitual behaviors, can reduce the incidence of lithium-induced dysfunction of the kidneys.
Obesity Associated with Inflammation and Brain Abnormalities
At the 2019 meeting of the International Society for Bipolar Disorders, researcher David J. Bond reviewed the data on the multiple adverse effects of obesity in patients with bipolar disorder. These include increased cardiovascular risk, poorer response to treatment, brain abnormalities, and decreased cognitive function, which is correlated with the degree of overweight.
Editor’s Note: These data emphasize the importance of starting a nutritious diet early in life and sustaining it through adulthood, avoiding the drugs most associated with weight gain such as clozapine and olanzapine, and facilitating weight loss with drugs. There are several treatments that can aid in weight loss. One is the diabetes treatment metformin, starting at a high dose of 500mg twice daily, and increasing to 1000mg twice daily if tolerated. The anticonvulsants topiramate or zonisamide also promote weight loss. The most effective option is a combination of the antidepressant bupropion sustained release (at a dose of 150–300mg) plus the anti–substance abuse drug naltrexone (50mg). This combination was associated with a loss of 10% of body weight over 12 weeks in women with diabetes.
Red Meat Interacts with Bacteria in the Gut to Raise Heart Disease Risk
A 2018 study by a group of researchers at the Cleveland Clinic have clarified the way that a diet heavy in red meat may lead to heart disease. The research centers on trimethylamine N-oxide (TMAO), a gut bacteria byproduct that is formed during digestion. When gut bacteria digest choline, lecithin, and carnitine, nutrients that are common in certain animal products and red meat, TMAO is produced.
In an article by Robert A. Koeth and colleagues in the European Heart Journal, the researchers show that diets that rely on red meat as the main protein source lead to more circulating TMAO than diets in which white meat or something other than meat is the primary source of protein. They found that in people who eat a lot of red meat, the kidneys are less efficient at expelling TMAO, and levels creep even higher. High levels of TMAO have been linked to hardening and narrowing of the arteries (atherosclerosis) and heart disease complications. High levels of TMAO in the blood can be a predictor of heart attack, stroke, and death.
The study of 113 participants consisted of three different diets that each participant followed in random order (with a washout period in between each diet). A month of eating a diet in which red meat was responsible for at least 25% of participants’ daily calories led to higher levels of TMAO in the blood and urine. TMAO increased threefold during the red meat diet periods compared to periods in which white meat or non-meat protein were the source of those calories, and in certain participants, TMAO increased as much as tenfold. When participants stopped eating the red meat diet, their TMAO levels fell over the following month.
