Steven P. Ellis

Meta-analysis of the effects of eicosapentaenoic acid (EPA) in clinical trials in depression.

OBJECTIVE Randomized trials of omega-3 polyunsaturated fatty acid (PUFA) treatment for depression have differed in outcome. Recent meta-analyses ascribe discrepancies to differential effects of eicosapentaenoic acid (EPA) versus docosahexaenoic acid (DHA) and to diagnostic heterogeneity. This meta-analysis tests the hypothesis that EPA is the effective component in PUFA treatment of major depressive episodes. DATA SOURCES PubMed/MeSH was searched for studies published in English from 1960 through June 2010 using the terms fish oils (MeSH) AND (depressive disorder [MeSH] OR bipolar depression) AND randomized controlled trial (publication type). The search was supplemented by manual bibliography review and examination of relevant review articles. STUDY SELECTION The search yielded 15 trials involving 916 participants. Studies were included if they had a prospective, randomized, double-blinded, placebo-controlled study design; if depressive episode was the primary complaint (with or without comorbid medical conditions); if omega-3 PUFA supplements were administered; and if appropriate outcome measures were used to assess depressed mood. DATA EXTRACTION Extracted data included study design, sample sizes, doses and percentages of EPA and DHA, mean ages, baseline and endpoint depression ratings and standard deviations for PUFA and placebo groups, and P values. The clinical outcome of interest was the standardized mean difference in the change from baseline to endpoint scores on a depression rating scale in subjects taking PUFA supplements versus subjects taking placebo. DATA SYNTHESIS In a mixed-effect model, percentage of EPA in the supplements was the fixed-effect predictor, dichotomized into 2 groups: EPA < 60% or EPA ≥ 60% of the total EPA + DHA. Secondary analyses explored the relevance of treatment duration, age, and EPA dose. RESULTS Supplements with EPA ≥ 60% showed benefit on standardized mean depression scores (effect size = 0.532; 95% CI, 0.277-0.733; t = 4.195; P < .001) versus supplements with EPA < 60% (effect size = -0.026; 95% CI, -0.200 to 0.148; t = -0.316; P = .756), with negligible contribution of random effects or heteroscedasticity and with no effects of treatment duration or age. Supplements with EPA < 60% were ineffective. Exploratory analyses supported a nonlinear model, with improvement determined by the dose of EPA in excess of DHA, within the range of 200 to 2,200 mg/d of EPA. CONCLUSIONS Supplements containing EPA ≥ 60% of total EPA + DHA, in a dose range of 200 to 2,200 mg/d of EPA in excess of DHA, were effective against primary depression. Translational studies are needed to determine the mechanisms of EPAs therapeutic benefit.

Aggressivity, suicide attempts, and depression: relationship to cerebrospinal fluid monoamine metabolite levels

BACKGROUND We have proposed a stress-diathesis model for suicidal behavior, in which major depression is a stressor and the diathesis is shared with aggression. Neurotransmitter correlates of the stress or diathesis have not been adequately evaluated by previous studies, because they did not simultaneously examine the relationship of multiple neurotransmitters to all three psychopathologies in the same population. In the present study we investigated the relationship of monoamine metabolites to aggressivity, suicidal behavior, and depression in patients with mood disorders. METHODS Ninety-three drug-free subjects with a major depressive episode underwent lumbar puncture and psychiatric evaluation. Cerebrospinal fluid CSF levels of 5hydroxyindolacetic acid (5-HIAA), homovanillic acid (HVA) and methoxy-hydroxy-phenylglycol (MHPG) were assayed. The relationships between monoamine metabolites and clinical variables were statistically evaluated. RESULTS Higher lifetime aggressivity correlated significantly with lower CSF 5-HIAA. Lower CSF 5-HIAA and greater suicidal intent were found in high-lethality suicide attempters compared with low-lethality suicide attempters. Low-lethality attempters did not differ biologically from nonattempters. No correlation between CSF HVA and any of the psychopathological variables was found. Only aggression showed a trend statistically in correlating positively with CSF MHPG levels. CONCLUSIONS Lower CSF 5-HIAA concentration was independently associated with severity of lifetime aggressivity and a history of a higher lethality suicide attempt and may be part of the diathesis for these behaviors. The dopamine and norepinephrine systems do not appear to be as significantly involved in suicidal acts, aggression, or depression. The biological correlates of suicide intent warrant further study.

Morphometry of the dorsal raphe nucleus serotonergic neurons in suicide victims

BACKGROUND The serotonin deficiency hypothesis of suicide has been important heuristically. Few studies have directly examined the brainstem dorsal raphe nucleus (DRN) serotonin neurons. We determined the number and morphometry of DRN serotonergic neurons in suicide victims (n = 7) compared to controls (n = 6). METHODS Brainstems were collected at autopsy, fixed and cryoprotected. Tissue was sectioned, stained for Nissl and processed with an antiserum that cross-reacts with tryptophan hydroxylase. All DRN neurons were identified, counted and analyzed every 1000 microns. Neuron morphometry was characterized by soma area (micron 2), sphericity, perimeter, length and density (neurons per mm3). RESULTS Neuron number and density was higher in suicide victims (1,780 +/- 127 neurons/mm3) than controls (1,349 +/- 68). The DRN volume did not differ between groups (66 +/- 9 mm3 for controls vs. 67 +/- 5 mm3 for suicides). Mean neuronal area and sphericity did not differ between suicides and controls. The total number and the density of DRN neurons did not correlate with age. CONCLUSIONS The finding of an increased number of neurons indicates that impaired serotonergic transmission found in association with serious suicide attempts is not due to fewer neurons.

Can biological tests assist prediction of suicide in mood disorders

Predicting suicide is difficult due to its low base-rate and the limited specificity of clinical predictors. Prospective biological studies suggest that dysfunctions in the serotonergic system and hypothalamic-pituitary-adrenal axis have some predictive power for completed suicide in mood disorders. A prediction model that incorporates biological testing to increase specificity and sensitivity of prediction of suicide is of potential clinical value. Meta-analyses of prospective biological studies of suicide and cerebrospinal fluid 5-hydroxyindoleacetic acid (CSF 5-HIAA) and suicide and the dexamethasone suppression test (DST) in mood disorders using the penalized quasi-likelihood (PQL) and bootstrap method yield odds ratios for prediction of suicide of 4.48 and 4.65 respectively. Two combinatory prediction models, the first requiring positive results on more than one test, and the second requiring a positive result on either one of two tests, were tested to assess their sensitivity, specificity, and predictive power using biological data from published and unpublished studies. The prediction model that requires both DST and CSF 5-HIAA tests to be positive results in 37.5% sensitivity, 88% specificity, and has a positive predictive value of 23%. The prediction model that requires either DST or CSF 5-HIAA tests to be positive results in 87.5% sensitivity, 28% specificity, and has a positive predictive value of 10%. Thus, models attempting to predict a lethal outcome that is uncommon perform very differently making model choice of major importance. Further work on refining biological predictors and integration with clinical predictors is needed to optimize a model to predict suicide in the clinic.

Selective cognitive deficits in obsessive- compulsive disorder compared to panic disorder with agoraphobia

Objective:  Visual‐spatial and executive functions deficits have been reported in obsessive‐compulsive disorder (OCD). We investigated their specificity comparing cognitive function in OCD, panic disorder with agoraphobia (PD/A) and controls by a comprehensive neuropsychological battery.

Aggressiveness, not impulsiveness or hostility, distinguishes suicide attempters with major depression

BACKGROUND Impulsiveness, hostility and aggressiveness are traits associated with suicidal behavior, but also with borderline personality disorder (BPD). The presence of large numbers of BPD subjects in past attempter samples may distort the relative importance of each of these traits to predicting suicidal behavior, and lead to prospective, biological and genetic models that systematically misclassify certain subpopulations of suicidal individuals. METHOD Two hundred and seventy-five subjects with major depressive disorder (MDD), including 87 with co-morbid BPD (69 past suicide attempters, 18 non-attempters) and 188 without BPD (76 attempters, 112 non-attempters) completed standard impulsiveness, hostility and aggressiveness ratings. Differences between past suicide attempters and non-attempters were examined with the sample stratified by BPD status. RESULTS As expected, BPD subjects scored significantly higher than non-BPD subjects on all three trait measures. Stratifying by BPD status, however, eliminated attempter/non-attempter differences in impulsiveness and hostility in both patient subgroups. Past suicide attempters in each of the two subgroups of patients were only distinguished by higher levels of aggressiveness. CONCLUSIONS Once BPD is accounted for, a history of aggressive behavior appears to be the distinguishing trait characteristic of suicide attempters with major depression, rather than global personality dimensions such as impulsiveness or hostility. Aggressiveness, and not these related traits, may be the ideal target for behavioral, genetic and biological research on suicidal behavior, as well as for the clinical assessment of suicide risk.

Hippocampal pathology in schizophrenia : magnetic resonance imaging and spectroscopy studies

The hippocampus is a site of previously reported structural and functional abnormalities in schizophrenia. We used magnetic resonance imaging (MRI) and proton magnetic resonance spectroscopy (MRS) to measure gray matter volumes, the neuronal marker N-acetylaspartate (NAA), and the combination of glutamate (Glu), glutamine (Gln), and gamma-aminobutyric acid (GABA), designated Glx. Measurements were obtained of the medial temporal lobe, centered on the hippocampus, in 10 male patients with schizophrenia (3 neuroleptic-medicated and 7 medication-free), and 10 matched normal volunteers. MRI volumetric measurements and MRS data obtained with short echo time (TE=20 ms) one-dimensional STEAM chemical shift imaging (CSI) on a GE 1.5 Tesla Signa system were analyzed. A laterality index ¿(L-R)/(L+R) was generated from the ratio of Glx to choline-containing compounds (Cho) to test asymmetry changes. Reliability of the MRS measures was assessed with five test-retest studies of healthy volunteers and showed coefficients of variation (CV) in the range of 36-44% for the MRS ratios and standard deviations (S.D.) of 0.15-0.17 for the laterality indices. The Glx/Cho laterality index showed a relative right-sided excess in this region in the patients (-0.23+/-0.20) compared to the controls (+0.06+/-0.20), which was not confounded by tissue composition or placement variability of the MRS voxels. Hippocampal volume deficit and asymmetry were not significant, and other MRS measures showed no differences between patients and controls. The preliminary finding of a lateralized abnormality in Glx is consistent with postmortem findings of asymmetric neurochemical temporal lobe abnormalities in schizophrenia.

Higher postmortem prefrontal 5-HT2A receptor binding correlates with lifetime aggression in suicide

BACKGROUND In vivo studies find altered serotonin function associated with aggressive and suicidal behaviors. Postmortem studies also reveal serotonergic alterations in suicide subjects but have not reported on the relationship between aggression and the serotonin system. We measured 5-hydroxytryptamine 2A (5-HT(2A)) receptor binding in prefrontal cortex of suicide and nonsuicide subjects and explored the relationship between 5-HT(2A) receptor binding, lifetime aggression, and suicide. METHODS The 5-HT(2A) receptor binding in coronal sections of prefrontal cortex was quantified by autoradiography with [(3)H] ketanserin in 37 suicide subjects and 73 nonsuicide subjects. The relationship between [(3)H] ketanserin binding and lifetime aggression, rated on the Brown-Goodwin Aggression History Scale, was assessed controlling for age and sex. RESULTS In suicide subjects, lifetime aggression scores correlated positively with [(3)H] ketanserin binding in all prefrontal Brodmann areas examined, after adjusting for age and sex. This was not the case in nonsuicide subjects. We found no significant differences in aggression scores or [(3)H] ketanserin binding between the suicide subjects and nonsuicide subjects. CONCLUSIONS The relationship between aggression and 5-HT(2A) receptor binding in suicide subjects, but not in nonsuicide subjects, may reflect differences in the regulation of the 5-HT(2A) receptor related to suicidal behavior and perhaps other proaggressive changes in brains of suicide subjects.

Relationship of MAO-A promoter (u-VNTR) and COMT (V158M) gene polymorphisms to CSF monoamine metabolites levels in a psychiatric sample of caucasians: A preliminary report.

Monoamine oxidase A gene promoter (MAOA‐uVNTR) and catechol‐O‐methyltransferase V158M (COMT‐V158M) gene functional polymorphisms are reported to be associated with impulsive‐aggression, but a biological intermediate effect remains to be determined. This study assessed the association of these polymorphisms with cerebrospinal fluid (CSF) monoamine metabolites as endophenotypes. Ninety‐eight Caucasian psychiatric subjects were assessed for Axis I and II diagnosis. Subjects were genotyped for the functional polymorphisms, MAOA‐uVNTR and COMT‐V158M. CSF was obtained by lumbar puncture. Relationships of the two polymorphism to monoamine metabolites: HVA, 5‐HIAA, and MHPG were examined. The higher‐expressing MAOA‐uVNTR genotype was associated with higher CSF‐HVA levels in males only (n = 46) (195.80 pmol/ml, SD = 61.64 vs. 161.13, SD = 50.23, respectively; P = 0.042). No association was found with diagnosis. COMT‐V158M had no association with CSF monoamine metabolites. The association of MAOA‐uVNTR with dopaminergic activity in males is a preliminary finding that needs to be replicated in a larger sample of Caucasian males and relationships sought with clinical phenotypes. This article contains supplementary material, which may be viewed at the American Journal of Medical Genetics website at http://www.interscience.wiley.com/jpages/0148‐7299:1/suppmat/index.html.

Norepinephrine and serotonin imbalance in the locus coeruleus in bipolar disorder

OBJECTIVES Abnormalities in norepinephrine (NE) and serotonin (5-HT) are implicated in bipolar disorder (BD). We examined 5-HT input and NE neurons in the locus coeruleus (LC, the NE nucleus that innervates the forebrain) in BD by quantifying immunoreactivity (IR) for tyrosine hydroxylase (TH) and tryptophan hydroxylase (TPH), the biosynthetic enzymes for NE and 5-HT, respectively. METHODS Six suicides with BD were compared to matched normal controls and unipolar major depression suicides, using immunocytochemistry with computer-assisted quantification of immunoreactivity. RESULTS Depressed bipolar suicides had 26.7 +/- 1.3% of LC area occupied by the TH immunoreactive (TH-IR) process, while controls had 50.7 +/- 8% (p = 0.002) and unipolar depressed suicides had 50.3 +/- 2.5% (p = 0.003). In bipolars, these processes did not stain as darkly (1.9 +/- 0.5 x background) as controls (2.9 +/- 0.9 x background; p = 0.01) or unipolars (2.9 +/- 0.6 x background; p = 0.002). Bipolar suicides also had less TPH-IR processes in the LC (11.7 +/- 10%) compared with controls (32.8 +/- 8.8%; p = 0.01) or unipolar suicides (30.3 +/- 8%; p = 0.02). The TPH-IR intensity did not differ between groups. CONCLUSIONS We found less TH-IR and TPH-IR in the LC in depressed bipolar suicides, but not unipolar suicides, suggesting that both NE and 5-HT activity is lower in BD. Studies during manic or euthymic states will determine whether these changes are mood state dependent.