Genomics-based identification of a potential causal role for acylcarnitine metabolism in depression

BACKGROUND

Altered metabolism of acylcarnitines - transporting fatty acids to mitochondria - may link cellular energy dysfunction to depression. We examined the potential causal role of acylcarnitine metabolism in depression by leveraging genomics and Mendelian randomization.

METHODS

Summary statistics were obtained from large GWAS: the Fenland Study (N = 9363), and the Psychiatric Genomics Consortium (246,363 depression cases and 561,190 controls). Two-sample Mendelian randomization analyses tested the potential causal link of 15 endogenous acylcarnitines with depression.

RESULTS

In univariable analyses, genetically-predicted lower levels of short-chain acylcarnitines C2 (odds ratio [OR] 0.97, 95% confidence intervals [CIs] 0.95-1.00) and C3 (OR 0.97, 95%CIs 0.96-0.99) and higher levels of medium-chain acylcarnitines C8 (OR 1.04, 95%CIs 1.01-1.06) and C10 (OR 1.04, 95%CIs 1.02-1.06) were associated with increased depression risk. No reverse potential causal role of depression genetic liability on acylcarnitines levels was found. Multivariable analyses showed that the association with depression was driven by the medium-chain acylcarnitines C8 (OR 1.04, 95%CIs 1.02-1.06) and C10 (OR 1.04, 95%CIs 1.02-1.06), suggesting a potential causal role in the risk of depression. Causal estimates for C8 (OR = 1.05, 95%CIs = 1.02-1.07) and C10 (OR = 1.05, 95%CIs = 1.02-1.08) were confirmed in follow-up analyses using genetic instruments derived from a GWAS meta-analysis including up to 16,841 samples.

DISCUSSION

Accumulation of medium-chain acylcarnitines is a signature of inborn errors of fatty acid metabolism and age-related metabolic conditions. Our findings point to a link between altered mitochondrial energy production and depression pathogenesis. Acylcarnitine metabolism represents a promising access point for the development of novel therapeutic approaches for depression.

Pilot Study of Metabolomic Clusters as State Markers of Major Depression and Outcomes to CBT Treatment

Major depressive disorder (MDD) is a common and disabling syndrome with multiple etiologies that is defined by clinically elicited signs and symptoms. In hopes of developing a list of candidate biological measures that reflect and relate closely to the severity of depressive symptoms, so-called “state-dependent” biomarkers of depression, this pilot study explored the biochemical underpinnings of treatment response to cognitive behavior therapy (CBT) in medication-free MDD outpatients. Plasma samples were collected at baseline and week 12 from a subset of MDD patients (N = 26) who completed a course of CBT treatment as part of the Predictors of Remission in Depression to Individual and Combined Treatments (PReDICT) study. Targeted metabolomic profiling using the AbsoluteIDQ^® p180 Kit and LC-MS identified eight “co-expressed” metabolomic modules. Of these eight, three were significantly associated with change in depressive symptoms over the course of the 12-weeks. Metabolites found to be most strongly correlated with change in depressive symptoms were branched chain amino acids, acylcarnitines, methionine sulfoxide, and α-aminoadipic acid (negative correlations with symptom change) as well as several lipids, particularly the phosphatidlylcholines (positive correlation). These results implicate disturbed bioenergetics as an important state marker in the pathobiology of MDD. Exploratory analyses contrasting remitters to CBT versus those who failed the treatment further suggest these metabolites may serve as mediators of recovery during CBT treatment. Larger studies examining metabolomic change patterns in patients treated with pharmacotherapy or psychotherapy will be necessary to elucidate the biological underpinnings of MDD and the -specific biologies of treatment response.

Metabolomic signature of exposure and response to citalopram/escitalopram in depressed outpatients

Metabolomics provides valuable tools for the study of drug effects, unraveling the mechanism of action and variation in response due to treatment. In this study we used electrochemistry-based targeted metabolomics to gain insights into the mechanisms of action of escitalopram/citalopram focusing on a set of 31 metabolites from neurotransmitter-related pathways. Overall, 290 unipolar patients with major depressive disorder were profiled at baseline, after 4 and 8 weeks of drug treatment. The 17-item Hamilton Depression Rating Scale (HRSD17) scores gauged depressive symptom severity. More significant metabolic changes were found after 8 weeks than 4 weeks post baseline. Within the tryptophan pathway, we noted significant reductions in serotonin (5HT) and increases in indoles that are known to be influenced by human gut microbial cometabolism. 5HT, 5-hydroxyindoleacetate (5HIAA), and the ratio of 5HIAA/5HT showed significant correlations to temporal changes in HRSD17 scores. In the tyrosine pathway, changes were observed in the end products of the catecholamines, 3-methoxy-4-hydroxyphenylethyleneglycol and vinylmandelic acid. Furthermore, two phenolic acids, 4-hydroxyphenylacetic acid and 4-hydroxybenzoic acid, produced through noncanconical pathways, were increased with drug exposure. In the purine pathway, significant reductions in hypoxanthine and xanthine levels were observed. Examination of metabolite interactions through differential partial correlation networks revealed changes in guanosine-homogentisic acid and methionine-tyrosine interactions associated with HRSD17. Genetic association studies using the ratios of these interacting pairs of metabolites highlighted two genetic loci harboring genes previously linked to depression, neurotransmission, or neurodegeneration. Overall, exposure to escitalopram/citalopram results in shifts in metabolism through noncanonical pathways, which suggest possible roles for the gut microbiome, oxidative stress, and inflammation-related mechanisms.

A knowledge network for a dynamic taxonomy of psychiatric disease

Current taxonomic approaches in medicine and psychiatry are limited in validity and utility. They do serve simple communication purposes for medical coding, teaching, and reimbursement, but they are not suited for the modern era with its rapid explosion of knowledge from the “omics” revolution. The National Academy of Sciences published a report entitled Toward Precision Medicine: Building a Knowledge Network for Biomedical Research and a New Taxonomy of Disease. The authors advocate a new taxonomy that would integrate molecular data, clinical data, and health outcomes in a dynamic, iterative fashion, bringing together research, public health, and health-care delivery with the interlinked goals of advancing our understanding of disease pathogenesis and thereby improving health. As the need for an information hub and a knowledge network with a dynamic taxonomy based on integration of clinical and research data is vital, and timely, this proposal merits consideration.

Incubating the research independence of a medical scientist training program graduate: a case study

PROBLEM

Physician-scientists play a critical role in discovering new biological knowledge and translating findings into medical practices that can improve clinical outcomes. Collectively, the National Institutes of Health (NIH) and its affiliated Medical Scientist Training Programs (MSTPs) invest upwards of $500,000 to fully train each of the 900+ MD/PhD students enrolled in these programs. Nevertheless, graduates face the challenges of navigating fragmented intervals of clinical training and research engagement, reinitiating research upon completing their residencies, managing financial pressures, and competing for funding following what is typically four or more years of research inactivity. Together, these barriers contribute to the high attrition rate of MSTP graduates from research careers.

APPROACH

The authors designed and implemented (2009-2014), for a single trainee, an alternative postgraduate training model characterized by early research engagement, strategic mentoring, unyoked clinical and research milestones, and dedicated financial support.

OUTCOMES

The pilot training experiment was so successful that the trainee secured an NIH project grant and completed his transition to research independence 3.5 years after starting the experimental training schedule-nearly 9 years earlier (based on age) than is typical for MD/PhDs transitioning from mentored to independent research. This success has demonstrated that unyoking research engagement from conventional calendar-based clinical training milestones is a feasible, effective means of incubating research independence in MSTP graduates.

NEXT STEPS

The authors encourage the design and application of similar unconventional approaches that interweave residency training with ongoing research activity for appropriate candidates, especially in subspecialties with increased MSTP graduate enrollment.

Pharmacometabolomics of response to sertraline and to placebo in major depressive disorder - possible role for methoxyindole pathway

Therapeutic response to selective serotonin (5-HT) reuptake inhibitors in Major Depressive Disorder (MDD) varies considerably among patients, and the onset of antidepressant therapeutic action is delayed until after 2 to 4 weeks of treatment. The objective of this study was to analyze changes within methoxyindole and kynurenine (KYN) branches of tryptophan pathway to determine whether differential regulation within these branches may contribute to mechanism of variation in response to treatment. Metabolomics approach was used to characterize early biochemical changes in tryptophan pathway and correlated biochemical changes with treatment outcome. Outpatients with MDD were randomly assigned to sertraline (n = 35) or placebo (n = 40) in a double-blind 4-week trial; response to treatment was measured using the 17-item Hamilton Rating Scale for Depression (HAMD₁₇). Targeted electrochemistry based metabolomic platform (LCECA) was used to profile serum samples from MDD patients. The response rate was slightly higher for sertraline than for placebo (21/35 [60%] vs. 20/40 [50%], respectively, χ²(1)  = 0.75, p = 0.39). Patients showing a good response to sertraline had higher pretreatment levels of 5-methoxytryptamine (5-MTPM), greater reduction in 5-MTPM levels after treatment, an increase in 5-Methoxytryptophol (5-MTPOL) and Melatonin (MEL) levels, and decreases in the (KYN)/MEL and 3-Hydroxykynurenine (3-OHKY)/MEL ratios post-treatment compared to pretreatment. These changes were not seen in the patients showing poor response to sertraline. In the placebo group, more favorable treatment outcome was associated with increases in 5-MTPOL and MEL levels and significant decreases in the KYN/MEL and 3-OHKY/MEL; changes in 5-MTPM levels were not associated with the 4-week response. These results suggest that recovery from a depressed state due to treatment with drug or with placebo could be associated with preferential utilization of serotonin for production of melatonin and 5-MTPOL.

Pharmacometabolomic mapping of early biochemical changes induced by sertraline and placebo

In this study, we characterized early biochemical changes associated with sertraline and placebo administration and changes associated with a reduction in depressive symptoms in patients with major depressive disorder (MDD). MDD patients received sertraline or placebo in a double-blind 4-week trial; baseline, 1 week, and 4 weeks serum samples were profiled using a gas chromatography time of flight mass spectrometry metabolomics platform. Intermediates of TCA and urea cycles, fatty acids and intermediates of lipid biosynthesis, amino acids, sugars and gut-derived metabolites were changed after 1 and 4 weeks of treatment. Some of the changes were common to the sertraline- and placebo-treated groups. Changes after 4 weeks of treatment in both groups were more extensive. Pathway analysis in the sertraline group suggested an effect of drug on ABC and solute transporters, fatty acid receptors and transporters, G signaling molecules and regulation of lipid metabolism. Correlation between biochemical changes and treatment outcomes in the sertraline group suggested a strong association with changes in levels of branched chain amino acids (BCAAs), lower BCAAs levels correlated with better treatment outcomes; pathway analysis in this group revealed that methionine and tyrosine correlated with BCAAs. Lower levels of lactic acid, higher levels of TCA/urea cycle intermediates, and 3-hydroxybutanoic acid correlated with better treatment outcomes in placebo group. Results of this study indicate that biochemical changes induced by drug continue to evolve over 4 weeks of treatment and that might explain partially delayed response. Response to drug and response to placebo share common pathways but some pathways are more affected by drug treatment. BCAAs seem to be implicated in mechanisms of recovery from a depressed state following sertraline treatment.

Treatment course with antidepressant therapy in late-life depression

OBJECTIVE

In order to assess the effect of gray matter volumes and cortical thickness on antidepressant treatment response in late-life depression, the authors examined the relationship between brain regions identified a priori and Montgomery-Åsberg Depression Rating Scale (MADRS) scores over the course of an antidepressant treatment trial.

METHOD

In a nonrandomized prospective trial, 168 patients who were at least 60 years of age and met DSM-IV criteria for major depression underwent MRI and were enrolled in a 12-week treatment study. Exclusion criteria included cognitive impairment or severe medical disorders. The volumes or cortical thicknesses of regions of interest that differed between the depressed group and a comparison group (N=50) were determined. These regions of interest were used in analyses of the depressed group to predict antidepressant treatment outcome. Mixed-model analyses adjusting for age, education, age at depression onset, race, baseline MADRS score, scanner, and interaction with time examined predictors of MADRS scores over time.

RESULTS

Smaller hippocampal volumes predicted a slower response to treatment. With the inclusion of white matter hyper-intensity severity and neuropsychological factor scores, the best model included hippocampal volume and cognitive processing speed to predict rate of response over time. A secondary analysis showed that hippocampal volume and frontal pole thickness differed between patients who achieved remission and those who did not.

CONCLUSIONS

These data expand our understanding of the prediction of treatment course in late-life depression. The authors propose that the primary variables of hippocampal volume and cognitive processing speed, subsuming other contributing variables (episodic memory, executive function, language processing) predict antidepressant response.

AGTR1 gene variation: association with depression and frontotemporal morphology

The renin-angiotensin system (RAS) is implicated in the response to physiological and psychosocial stressors, but its role in stress-related psychiatric disorders is poorly understood. We examined if variation in AGTR1, the gene coding for the type 1 angiotensin II receptor (AT(1)R), is associated with a diagnosis of depression and differences in white matter hyperintensities and frontotemporal brain volumes. Participants comprised 257 depressed and 116 nondepressed elderly Caucasian subjects who completed clinical assessments and provided blood samples for genotyping. We used a haplotype-tagging single nucleotide polymorphism (htSNP) analysis to test for variation in AGTR1. For measurement of hyperintense lesions, 1.5 Tesla magnetic resonance imaging (MRI) data were available on 33 subjects. For measurements of the hippocampus and dorsolateral prefrontal cortex (dlPFC), 3 Tesla MRI data were available on 70 subjects. Two htSNPs exhibited statistically significant frequency differences between diagnostic cohorts: rs10935724 and rs12721331. Although hyperintense lesion volume did not significantly differ by any htSNP, dlPFC and hippocampus volume differed significantly for several htSNPs. Intriguingly, for those htSNPs differing significantly for both dlPFC and hippocampus volume, the variant associated with smaller dlPFC volume was associated with larger hippocampal volume. This supports the idea that genetic variation in AGTR1 is associated with depression and differences in frontotemporal morphology.

Fiber tract-specific white matter lesion severity Findings in late-life depression and by AGTR1 A1166C genotype

Past work demonstrated that late-life depression is associated with greater severity of ischemic cerebral hyperintense white matter lesions, particularly frontal lesions. However, these lesions are also associated with other neuropsychiatric deficits, so these clinical relationships may depend on which fiber tracts are damaged. We examined the ratio of lesion to nonlesioned white matter tissue within multiple fiber tracts between depressed and nondepressed elders. We also sought to determine if the AGTR1 A1166C and BDNF Val66Met polymorphisms contributed to vulnerability to lesion development in discrete tracts. The 3T structural MR images and blood samples for genetic analyses were acquired on 54 depressed and 37 nondepressed elders. Lesion maps were created through an automated tissue segmentation process and applied to a probabilistic white matter fiber tract atlas allowing for identification of the fraction of the tract occupied by lesion. The depressed cohort exhibited a significantly greater lesion ratio only in the left upper cingulum near the cingulate gyrus (F((1,86)) = 4.62, P = 0.0344), supporting past work implicating cingulate dysfunction in the pathogenesis of depression. In the 62 Caucasian subjects with genetic data, AGTR1 C1166 carriers exhibited greater lesion ratios across multiple tracts including the anterior thalamic radiation and inferior fronto-occipital fasciculus. In contrast, BDNF Met allele carriers exhibited greater lesion ratios only in the frontal corpus callosum. Although these findings did not survive correction for multiple comparisons, this study supports our hypothesis and provides preliminary evidence that genetic differences related to vascular disease may increase lesion vulnerability differentially across fiber tracts.

Comprehensive model of how reality distortion and symptoms occur in schizophrenia: could impairment in learning-dependent predictive perception account for the manifestations of schizophrenia?

Conventional wisdom has not laid out a clear and uniform profile of schizophrenia as a unitary entity. One of the key first steps in elucidating the neurobiology of this entity would be to characterize the essential and common elements in the group of entities called schizophrenia. Kraepelin in his introduction notes 'the conviction seems to be more and more gaining ground that dementia praecox on the whole represents, a well characterized form of disease, and that we are justified in regarding the majority of the clinical pictures which are brought together here as the expression of a single morbid process, though outwardly they often diverge very far from one another'. But what is that single morbid process? We suggest that just as the uniform defect in all types of cancer is impaired regulation of cell proliferation, the primary defect in the group of entities called schizophrenia is persistent defective hierarchical temporal processing. This manifests in the form of chronic memory-prediction errors or deficits in learning-dependent predictive perception. These deficits account for the symptoms that present as reality distortion (delusions, thought disorder and hallucinations). This constellation of symptoms corresponds with the profile of most patients currently diagnosed as suffering from schizophrenia. In this paper we describe how these deficits can lead to the various symptoms of schizophrenia.

Hierarchical temporal processing deficit model of reality distortion and psychoses

We posit in this article that hierarchical temporal processing deficit is the underlying basis of reality distortion and psychoses. Schizophrenia is a prototypical reality distortion disorder in which the patient manifests with auditory hallucinations, delusions, disorganized speech and thinking, cognitive impairment, avolition and social and occupational dysfunction. Reality distortion can be present in many other disorders including bipolar disorder, major depression and even dementia. Conceptually, schizophrenia is a heterogeneous entity likely to be because of numerous causes similar to dementia. Although no single symptom or set of symptoms is pathognomonic, a cardinal feature in all patients with schizophrenia is chronic distortion of reality. The model that we have proposed accounts for the varied manifestations of reality distortion including hallucinations and delusions. In this paper we consider the implications of this model for the underlying biology of psychoses and also for the neurobiology of schizophrenia and suggest potential targets to consider for the etiology and pathophysiology of reality distortion, especially in the context of schizophrenia.

Altered interactions of tryptophan metabolites in first-episode neuroleptic-naive patients with schizophrenia

Schizophrenia is characterized by complex and dynamically interacting perturbations in multiple neurochemical systems. In the past, evidence for these alterations has been collected piecemeal, limiting our understanding of the interactions among relevant biological systems. Earlier, both hyper- and hyposerotonemia were variously associated with the longitudinal course of schizophrenia, suggesting a disturbance in the central serotonin (5-hydroxytryptamine (5-HT)) function. Using a targeted electrochemistry-based metabolomics platform, we compared metabolic signatures consisting of 13 plasma tryptophan (Trp) metabolites simultaneously between first-episode neuroleptic-naive patients with schizophrenia (FENNS, n=25) and healthy controls (HC, n=30). We also compared these metabolites between FENNS at baseline (BL) and 4 weeks (4w) after antipsychotic treatment. N-acetylserotonin was increased in FENNS-BL compared with HC (P=0.0077, which remained nearly significant after Bonferroni correction). N-acetylserotonin/Trp and melatonin (Mel)/serotonin ratios were higher, and Mel/N-acetylserotonin ratio was lower in FENNS-BL (all P-values<0.0029), but not after treatment, compared with HC volunteers. All three groups had highly significant correlations between Trp and its metabolites, Mel, kynurenine, 3-hydroxykynurenine and tryptamine. However, in the HC, but in neither of the FENNS groups, serotonin was highly correlated with Trp, Mel, kynurenine or tryptamine, and 5-hydroxyindoleacetic acid (5HIAA) was highly correlated with Trp, Mel, kynurenine or 3-hydroxykynurenine. A significant difference between HC and FENNS-BL was further shown only for the Trp-5HIAA correlation. Thus, some metabolite interactions within the Trp pathway seem to be altered in the FENNS-BL patients. Conversion of serotonin to N-acetylserotonin by serotonin N-acetyltransferase may be upregulated in FENNS patients, possibly related to the observed alteration in Trp-5HIAA correlation. Considering N-acetylserotonin as a potent antioxidant, such increases in N-acetylserotonin might be a compensatory response to increased oxidative stress, implicated in the pathogenesis of schizophrenia.

Support for the vascular depression hypothesis in late-life depression: results of a 2-site, prospective, antidepressant treatment trial

CONTEXT

Research on vascular depression has used 2 approaches to subtype late-life depression, based on executive dysfunction or white matter hyperintensity severity.

OBJECTIVE

To evaluate the relationship of neuropsychological performance and white matter hyperintensity with clinical response in late-life depression.

DESIGN

Two-site, prospective, nonrandomized controlled trial.

SETTING

Outpatient clinics at Washington University and Duke University.

PARTICIPANTS

A total of 217 subjects aged 60 years or older met DSM-IV criteria for major depression, scored 20 or more on the Montgomery-Asberg Depression Rating Scale (MADRS), and received vascular risk factor scores, neuropsychological testing, and magnetic resonance imaging; they were excluded for cognitive impairment or severe medical disorders. Fazekas rating was conducted to grade white matter hyperintensity lesions. Intervention Twelve weeks of sertraline treatment, titrated by clinical response. Main Outcome Measure Participants' MADRS scores over time.

RESULTS

Baseline neuropsychological factor scores correlated negatively with baseline Fazekas scores. A mixed model examined effects of predictor variables on MADRS scores over time. Baseline episodic memory (P = .002), language (P = .007), working memory (P = .01), processing speed (P < .001), executive function factor scores (P = .002), and categorical Fazekas ratings (P = .05) predicted MADRS scores, controlling for age, education, age of onset, and race. Controlling for baseline MADRS scores, these factors remained significant predictors of decrease in MADRS scores, except for working memory and Fazekas ratings. Thirty-three percent of subjects achieved remission (MADRS < or =7). Remitters differed from nonremitters in baseline cognitive processing speed, executive function, language, episodic memory, and vascular risk factor scores.

CONCLUSIONS

Comprehensive neuropsychological function and white matter hyperintensity severity predicted MADRS scores prospectively over a 12-week treatment course with selective serotonin reuptake inhibitors in late-life depression. Baseline neuropsychological function differentiated remitters from nonremitters and predicted time to remission in a proportional hazards model. Predictor variables correlated highly with vascular risk factor severity. These data support the vascular depression hypothesis and highlight the importance of linking subtypes based on neuropsychological function and white matter integrity.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00045773.

Functional evidence implicating a novel TOR1A mutation in idiopathic, late-onset focal dystonia

BACKGROUND

TOR1A encodes a chaperone-like AAA-ATPase whose Delta GAG (Delta E) mutation is responsible for an early onset, generalised dystonia syndrome. Because of the established role of the TOR1A gene in heritable generalised dystonia (DYT1), a potential genetic contribution of TOR1A to the more prevalent and diverse presentations of late onset, focal dystonia has been suggested.

RESULTS

A novel TOR1A missense mutation (c.613T-->A, p.F205I) in a patient with late onset, focal dystonia is reported. The mutation occurs in a highly evolutionarily conserved region encoding the AAA-ATPase domain. Expression assays revealed that expression of F205I or Delta E, but not wildtype TOR1A, produced frequent intracellular inclusions.

CONCLUSIONS

A novel, rare TOR1A variant has been identified in an individual with late onset, focal dystonia and evidence provided that the mutation impairs TOR1A function. Together these findings raise the possibility that this novel TOR1A variant may contribute to the expression of dystonia. In light of these findings, a more comprehensive genetic effort is warranted to identify the role of this and other rare TOR1A variants in the expression of late onset, focal dystonia.

Reductions in neuronal density in elderly depressed are region specific

OBJECTIVE

Frontal regions, including the orbitofrontal cortex (ORB) and dorsolateral prefrontal cortex (dlPFC) have been implicated in the neuropathology of geriatric depression. Prominent reductions in pyramidal neuron density have been recently reported in the ORB of older depressed subjects. However, the cellular pathology of the dlPFC has not yet been examined in these subjects.

METHODS

Postmortem tissue from the dlPFC (Brodmann's area 9, BA9) was collected from 10 older (>60 years old) subjects diagnosed with major depression and 10 age-matched non-psychiatric controls (CTRL). The majority of the subjects were the same as those used for our previous study on neuronal reductions in the ORB in older depressed. Overall (all six layers combined), and laminar density of pyramidal (presumably glutamatergic), and non-pyramidal (GABAergic) neurons as well as cortical and laminar width were measured using linear optical disector of Stereoinvestigator software.

RESULTS

Neither the overall nor laminar density of pyramidal or non-pyramidal neurons was significantly different between groups. The cortical and laminar widths were also not affected.

CONCLUSIONS

These results suggest that neuronal prefrontal pathology in elderly depressed is region specific. No significant changes were detected in the density of any type of neurons in the dlPFC of elderly depressed subjects (present study) whereas, prominent reductions in the density of pyramidal glutamatergic neurons were observed previously in the ORB.

Schizophrenia is a disorder of higher order hierarchical processing

Schizophrenia is a mental disorder in which the patient manifests with auditory hallucinations, paranoid or bizarre delusions, and disorganized speech and thinking. It is associated with significant social dysfunction. There are many hypotheses regarding schizophrenia. Most of these focus on schizophrenia as a manifestation of abnormalities from genetic [Mulle JG. Genomic structural variation and schizophrenia. Curr Psychiatry Rep 2008;10(2):171-7], viral [Fruntes V, Limosin F. Schizophrenia and viral infection during neurodevelopment: a pathogenesis model? Med Sci Monit 2008;14(6):RA71-7], neurochemical [e.g. dopamine (Lewis DA, Akil M. Cortical dopamine in schizophrenia: strategies for postmortem studies. J Psychiatr Res 1997;31(2):175-95) or interactions between neurotransmitters (Duncan GE, Sheitman BB, Lieberman JA. An integrated view of pathophysiological models of schizophrenia. Brain Res Brain Res Rev 1999;29(2):250-64)] or brain structural [Kotrla KJ, Weinberger DR. Brain imaging in schizophrenia. Annu Rev Med 1995;46:113-22] origins. Most of these hypotheses do not account for how or why these presumed causes lead to the manifestations of schizophrenia. We argue that brain structure and function is compatible with a hierarchical processing structure that forms the basis for perception and thought in healthy humans. We propose that perturbations of the types listed above lead to disruption of higher levels of perception and hierarchical temporal processing by the brain and that this constitutes the core deficit in schizophrenia. We present evidence that this model explains many of the features of schizophrenia and we make a series of predictions about schizophrenia.

Antidepressant use, depression, and survival in patients with heart failure

BACKGROUND

Recent studies suggest that the use of antidepressants may be associated with increased mortality in patients with cardiac disease. Because depression has also been shown to be associated with increased mortality in these patients, it remains unclear if this association is attributable to the use of antidepressants or to depression.

METHODS

To evaluate the association of long-term mortality with antidepressant use and depression, we studied 1006 patients aged 18 years or older with clinical heart failure and an ejection fraction of 35% or less (62% with ischemic disease) between March 1997 and June 2003. The patients were followed up for vital status annually thereafter. Depression status, which was assessed by the Beck Depression Inventory (BDI) scale and use of antidepressants, was prospectively collected. The main outcome of interest was long-term mortality.

RESULTS

Of the study patients, 30.0% were depressed (defined by a BDI score > or =10) and 24.2% were taking antidepressants (79.6% of these patients were taking selective serotonin reuptake inhibitors [SSRIs] only). The vital status was obtained from all participants at an average follow-up of 972 (731) (mean [SD]) days. During this period, 42.7% of the participants died. Overall, the use of antidepressants (unadjusted hazard ratio [HR], 1.32; 95% confidence interval [CI], 1.03-1.69) or SSRIs only (unadjusted HR, 1.32; 95% CI, 0.99-1.74) was associated with increased mortality. However, the association between antidepressant use (HR, 1.24; 95% CI, 0.94-1.64) and increased mortality no longer existed after depression and other confounders were controlled for. Nonetheless, depression remained associated with increased mortality (HR, 1.33; 95% CI, 1.07-1.66). Similarly, depression (HR, 1.34; 95% CI, 1.08-1.68) rather than SSRI use (HR, 1.10; 95% CI, 0.81-1.50) was independently associated with increased mortality after adjustment.

CONCLUSION

Our findings suggest that depression (defined by a BDI score > or =10), but not antidepressant use, is associated with increased mortality in patients with heart failure.

Prefrontal mechanisms for executive control over emotional distraction are altered in major depression

A dysfunction in the interaction between executive function and mood regulation has been proposed as the pathophysiology of depression. However, few studies have investigated the alteration in brain systems related to executive control over emotional distraction in depression. To address this issue, 19 patients with major depressive disorder (MDD) and 20 healthy controls were scanned using functional magnetic resonance imaging. Participants performed an emotional oddball task in which infrequently presented circle targets required detection while sad and neutral pictures were irrelevant novel distractors. Hemodynamic responses were compared for targets, sad distractors, and for targets that followed sad or neutral distractors (Target-after-Sad and Target-after-Neutral). Patients with MDD revealed attenuated activation overall to targets in executive brain regions. Behaviorally, MDD patients were slower in response to Target-after-Sad than Target-after-Neutra stimuli. Patients also revealed a reversed activation pattern from controls in response to this contrast in the left anterior cingulate, insula, right inferior frontal gyrus (IFG), and bilateral middle frontal gyrus. Those patients who engaged the right IFG more during Target-after-Neutral stimuli responded faster to targets, confirming a role of this region in coping with emotional distraction. The results provide direct evidence of an alteration in the neural systems that interplay cognition with mood in MDD.

Hippocampal volumes and depression subtypes

Studies of depression and hippocampal volume have yielded inconsistent results. This inconsistency could stem from the heterogeneity of depressive disorders. We conducted cross-sectional and longitudinal analyses of hippocampal volumes in atypical depressive, melancholic depressive, and control subjects. We found no effect of depression subtype on hippocampal volume or memory performance.

Relationship between depressive symptoms and long-term mortality in patients with heart failure

BACKGROUND

Depression is prevalent in patients with heart failure (HF) and is associated with short-term poor prognosis. However, the long-term effect of depression and the use of self-administered depression evaluation on HF prognosis remained unknown. The study sought to assess the association of depressive symptoms and long-term mortality of patients with HF and to explore the prognostic predictability of the Beck Depression Inventory (BDI) scale for patients with HF.

METHODS

Hospitalized patients with HF between March 1997 and June 2003 were recruited. All participants were given the self-administered BDI scale for depression assessment during the index admission. They were then followed for 6 months for the collection of vital status, and annually thereafter.

RESULTS

Total study population comprises 1006 patients. The mean BDI score was 8.3 +/- 7.1. The average days of follow-up were 971 +/- 730 and the vital status was obtained from all participants. During this period, 42.6% of the participants died. Depression (defined by BDI score > or = 10) was significantly and independently associated with reduced survival (adjusted hazard ratio 1.36, 95% CI 1.09-1.70, P < .001). Patients whose BDI scores were 5 to 9, 10 to 18, and > or = 19 were 21%, 53%, and 83% more likely to die, respectively, than patients whose BDI score was < 5 (P < .001).

CONCLUSIONS

Self-rated depression by BDI is independently linked with higher long-term mortality in patients with HF. Significant dose effect of depressive symptoms on higher mortality is noted.

Structural integrity of the uncinate fasciculus in geriatric depression: Relationship with age of onset

BACKGROUND

The uncinate fasciculus connects limbic structures, such as the hippocampus and amygdala, with frontal regions. This study utilized diffusion tensor imaging to examine the structural integrity of the uncinate fasciculus in late-life depression.

METHOD

18 elderly depressed and 19 elderly nondepressed subjects were matched for age and sex; 8 subjects had mid- to late-onset of depression while 10 subjects had early-onset depression. 3T diffusion tensor imaging-based fiber tract mapping delineated the uncinate fasciculus in each hemisphere, which guided measurement of the fractional anisotropy of the uncinate fasciculus in the temporal stem. After controlling for age and sex, differences between diagnostic groups were assessed.

RESULTS

After controlling for age and sex, individuals with early onset depression exhibited lower anisotropy of the left uncinate fasciculus than did mid- and late-onset or nondepressed subjects (F(2,36) = 4.50, p = 0.02). Analyses of the right uncinate fasciculus were not statistically significant.

CONCLUSIONS

This provides preliminary evidence that there is a structural connectivity deficit between left frontal and limbic structures in early-onset depression. Further work is needed to determine if this is seen in younger depressed subjects, and if it influences treatment outcomes.

Differences in brain volumes among males and female hormone-therapy users and nonusers

Numerous studies have shown gender differences in the brain volumes of elderly adults. Some evidence shows that higher estrogen levels may be neuroprotective, suggesting that hormone therapy (HT) may in part be responsible for these gender differences; however, few studies have examined the relation between HT and brain volumes. Brain volumes of caudate, putamen, hippocampus, gray matter, white matter, white-matter lesions, and cerebrospinal fluid were measured on magnetic resonance imaging scans. A comprehensive neuropsychological battery was administered. Women were separated into two groups based on HT use, and we used multiple regression analyses to compare these groups with one another and with men. Results of brain-volume measurements showed that HT users had significantly less gray matter and more cerebrospinal fluid than nonusers. Results of the neuropsychological testing showed that HT users performed better on the Shipley Vocabulary Test than males did.

Aging, gender, and the elderly adult brain: an examination of analytical strategies

We sought to examine the relations between age, gender and brain volumes in an elderly population; we also sought to examine ways of measuring these relations. Three sets of analyses were used: correlational analyses, in which correlations between independent variables and brain volumes were calculated without correction for intracranial volume (ICV); covariational analyses, in which ICV was used as a covariate in regression equations; and ratio analyses, in which the dependent variable was the ratio of brain volume to ICV. These analyses yielded similar results, except that (as expected) adjusting for ICV altered estimates of gender differences. Analyses of age showed decreases in left caudate, putamen, and right hippocampus and an increase in CSF, a result generally in accord with previous findings. However, we also found a significant decrease of white-matter volumes and no significant decrease in total gray-matter volumes. Correlational analyses showed that men did not always have larger volumes despite their larger head size; women generally had larger volumes after adjusting for ICV. We found no age-gender interactions.

Atypical antipsychotic drugs and diabetes mellitus in a large outpatient population: a retrospective cohort study

PURPOSE

Previous research has suggested an association between use of atypical antipsychotics and onset of diabetes mellitus. We sought to compare the incidence of new onset diabetes among patients receiving atypical antipsychotics, traditional antipsychotics or antidepressants.

METHODS

Retrospective cohort study of outpatients with claims for atypical antipsychotics (n = 10 265) compared to controls with claims for traditional antipsychotics (n = 4607), antidepressants (n = 60 856) or antibiotics (n = 59 878) in the administrative claims database of a large pharmaceutical benefit manager between June 2000 and May 2002. Main outcome measures were adjusted and unadjusted incidence rates of diabetes (new cases per 1000 per year) in a 12-month period, as measured using new prescriptions for antidiabetic drugs after a 6-month lead-in period.

RESULTS

Annual unadjusted incidence rates of diabetes (new cases per 1000 per year) were 7.5 for atypical antipsychotics, 11.3 for traditional antipsychotics, 7.8 for antidepressants and 5.1 for antibiotics. In multivariable analyses, age, male sex and Chronic Disease Score were associated with greater odds of diabetes onset. There were no statistically significant differences in outcome between the atypical antipsychotic, traditional antipsychotic and antidepressant groups. Multivariable comparisons among specific agents showed increased odds of diabetes for clozapine, olanzapine, ziprasidone and thioridazine (relative to risperidone), but these comparisons did not reach statistical significance.

CONCLUSIONS

In a large prescription claims database, outpatients taking atypical antipsychotics did not have higher rates of diabetes onset, compared to subjects taking traditional antipsychotics or antidepressants.

Perspectives on Depression, Mild Cognitive Impairment, and Cognitive Decline

CONTEXT

The public health implications of depression and cognitive impairment in late life are enormous. Cognitive impairment and late-life depression are associated with increased risk for subsequent dementia; however, investigations of these phenomena appear to be proceeding along separate tracks. OBJECTIVES AND DATA SOURCE: The National Institute of Mental Health organized the conference "Perspectives on Depression, Mild Cognitive Impairment, and Cognitive Decline" to consider how the varied perspectives might be better integrated to examine the associations among depression, mild cognitive impairment, and cognitive decline and to illuminate the common or distinct mechanisms involved in these associations.

DATA SYNTHESIS

The following 2 broad questions were addressed: (1) What gaps in our knowledge have the greatest public health significance? (2) Can we more efficiently use our research dollars and participant resources to fill these gaps? Meeting participants included grantees from the National Institute of Mental Health and the National Institute on Aging and program staff from the National Institute of Mental Health, the National Institute on Aging, and the National Institute of Neurological Disorders and Stroke.

CONCLUSIONS

One of the most important recommendations to emerge from the meeting discussions is for increased collaboration among clinical and epidemiological investigators whose work focuses in the area of depression with those working primarily in the area of memory disorders. Directions for future research were identified.

Prevalence of Atypical Antipsychotic Drug Use Among Commercially Insured Youths in the United States

BACKGROUND

Use of atypical antipsychotic medications in pediatric populations is increasing. Although previous studies have presented data by age or sex, none has documented sex-specific prevalence by age group.

OBJECTIVE

To estimate the 1-year prevalence of atypical antipsychotic use by age and sex among commercially insured youths in the United States.

DESIGN

Period prevalence study, January through December 2001.

SETTING

Administrative claims database of a large pharmaceutical benefit manager for 6 213 824 outpatients.

MAIN OUTCOME MEASURES

Period prevalence of outpatient prescription claims for atypical antipsychotic drugs among commercially insured, continuously enrolled youths.

RESULTS

The prevalence of atypical antipsychotic use was 267.1 per 100 000 subjects aged 19 years and younger (16 599/6 213 824) and was more than twice as high for male patients as for female patients, although male and female patients were nearly equally represented in the overall population. Prevalence peaked at 594.3 per 100 000 subjects among male patients aged 10 to 14 years and 291.0 per 100 000 subjects among female patients aged 15 to 19 years. Nearly one fourth (3830/16 599) of patients with a claim for an atypical antipsychotic were aged 9 years and younger, and nearly 80% of these (3021/3830) were boys.

CONCLUSIONS

Although evidence regarding the safety and efficacy of atypical antipsychotics in young children is limited, nearly one fourth of patients with claims for these drugs were aged 9 years or younger, and a large majority of these were boys. Understanding the long-term effects on the developing brain of early and prolonged exposure to atypical antipsychotics is crucial given their use in pediatric populations.

Prognostic value of anxiety and depression in patients with chronic heart failure

BACKGROUND

Anxiety is often present with depression and may be one of its manifestations. Although the adverse effects of depression in patients with chronic heart failure (CHF) have been well studied, the relation between anxiety and CHF prognosis has not been addressed. In a secondary analysis of data collected for a published study of depression and prognosis in patients with CHF, we examined the relations among anxiety, depression, and prognosis.

METHODS AND RESULTS

We measured symptoms of anxiety with the Spielberger State-Trait Anxiety Inventory (STAI) scale and symptoms of depression with the Beck Depression Inventory (BDI) scale in 291 patients with CHF hospitalized as a result of cardiac events. We followed up these patients for all-cause mortality over 1 year. The mean scores for state anxiety (State-A) and trait anxiety (Trait-A) were identical at 33.5; the mean BDI score was 8.7+/-7.6. State-A and Trait-A scores correlated highly with each other (r=0.85; P<0.01) and with BDI score (State-A, r=0.52; Trait-A, r=0.59; P<0.01). Cox proportional-hazards model with and without confounding variables showed no relation between State-A or Trait-A and 1-year mortality. BDI scores, however, significantly predicted increased mortality during 1-year follow-up (hazard ratio, 1.04 for each 1-unit increase; P<0.01).

CONCLUSIONS

Although anxiety and depression are highly correlated in CHF patients, depression alone predicts a significantly worse prognosis for these patients.

Enhanced expression of cytokines and chemokines by blood monocytes to in vitro lipopolysaccharide stimulation are associated with hostility and severity of depressive symptoms in healthy women

The current study investigated the relation of hostility and severity of depressive symptoms, separately and jointly, to the capacity of blood monocytes to secrete an array of cytokines when stimulated by bacterial lipopolysaccharide (LPS). Subjects were 44 healthy, non-smoking, premenopausal women (aged 23-49 years) not currently taking oral contraceptives. Data were collected during the follicular phase of the menstrual cycle. The Cook-Medley Hostility (Ho) scale and the Beck Depression Inventory (BDI) were used to assess hostility and severity of depressive symptoms, respectively. Dual-color flow cytometry was used to measure the total expression of interleukin (IL)-1alpha, IL-1beta, IL-8, tumor necrosis factor (TNF)-alpha, monocyte chemotactic protein (MCP)-1 and monocyte inflammatory protein (MIP)-1alpha in blood monocytes following 4 h in vitro LPS stimulation of whole blood. In analyses adjusting for age, body mass index (BMI), fasting cholesterol, alcohol use, race and 17beta-estradiol (E(2)), higher Ho scores were associated with greater LPS-stimulated expression of IL-1alpha (beta = 0.033, p = 0.02), IL-8 (beta = 0.046, p = 0.01) and IL-1beta (beta = 0.024, p = 0.06). Higher BDI scores were associated with greater expression of TNF-alpha (beta = 0.042, p = 0.02) and IL-8 (beta = 0.045, p = 0.04). The linear combination of Ho and BDI scores was significantly associated with IL-1beta (beta = 0.18, p = 0.057), IL-8 (beta = 0.36, p = 0.01), TNF-alpha (beta = 0.25, p = 0.03), and IL-1alpha (beta = 0.18, p < 0.07). Thus, in healthy women, these psychological risk factors, alone and in combination, induce a proinflammatory phenotype in circulating monocytes characterized by the up-regulation of proinflammatory cytokines, supporting the hypothesis that inflammation may be a key pathway whereby hostility and depressive symptoms contribute to atherosclerosis and subsequent coronary heart disease (CHD).

Should selective serotonin reuptake inhibitors be prescribed to all patients with ischemic heart disease?

Recent studies have uncovered more and more evidence demonstrating the adverse relationship between depression and ischemic heart disease. One of the most significant mechanisms that may explain the adverse relationship is the increased platelet activity, otherwise known as aggregation, observed to occur in patients with depression or ischemic heart disease. Platelet activity is further elevated in patients with depression and ischemic heart disease. Selective serotonin reuptake inhibitors are antidepressants and also act like platelet inhibitors. The results of large-scale clinical trials suggest that the use of selective serotonin reuptake inhibitors may reduce cardiac events in post-myocardial infarction patients or in those with unstable angina that may be related to the effects of selective serotonin reuptake inhibitors on platelet aggregation.

Enhanced platelet/endothelial activation in depressed patients with acute coronary syndromes: evidence from recent clinical trials

Platelets play a key role in the progression of acute coronary syndromes (ACS). Clinical depression alone is also associated with enhanced platelet activation. The purpose of this study was to compare concentrations of established biomarkers of enhanced platelet/endothelial activation in clinically depressed versus non-depressed patients enrolled in recent clinical trials for ACS. Two hundred and eighty-one baseline plasma samples from patients with acute myocardial infarction (ASSENT-2; n = 41), with ACS (PRONTO; n = 126) and with clinical depression plus previous acute coronary syndrome within 6 months (SADHART; n = 64), and from normal healthy controls (n = 50) were analyzed. Blood was drawn before applying any therapeutic strategies including interventions, thrombolytics, infusions, and selective serotonin re-uptake inhibitors. Platelet factor 4, beta-thromboglobulin, platelet/endothelial cell adhesion molecule-1, P-selectin, thromboxane, prostacyclin, vascular cell adhesion molecule-1, and E-selectin were measured by enzyme-linked immunosorbent assay by a single core laboratory. Patients with ACS exhibited a higher degree of platelet activation than controls independently of the presence of depression. Plasma levels of P-selectin, thromboxane, prostacyclin, and vascular cell adhesion molecule-1 were the highest in the acute myocardial infarction group when compared with ACS despite the presence or absence of clinical depression. Surprisingly, patients with ACS and depression exhibited the highest levels of platelet factor 4, beta-thromboglobulin, and platelet/endothelial cell adhesion molecule-1 when compared with myocardial infarction or angina patients without clinical depression. E-selectin plasma level was constantly elevated compared with controls but did not differ among the groups dependent on the incidence of depression. The depressed plus ACS group had higher plasma levels of all biomarkers compared with the non-depressed patients. Retrospective analysis of the data from several clinical trials reveals that clinical depression is associated with enhanced activation of platelet/endothelial biomarkers even above the level expected in ACS. These findings may contribute to the unfavorable outcome associated with clinical depression in patients with ACS.

The relation of severity of depressive symptoms to monocyte-associated proinflammatory cytokines and chemokines in apparently healthy men

OBJECTIVE

We examined the relation of severity of depressive symptoms to lipopolysaccharide-stimulated expression of monocyte-associated proinflammatory cytokines and chemokines in 53 nonsmoking, healthy men.

METHODS

Assessments of cytokine and chemokine expression and severity of depressive symptoms were conducted on the same day. The 21-item Beck Depression Inventory (BDI) was used to assess severity of depressive symptoms experienced during the week before study participation. Dual-color flow cytometry was used to determine monocyte-associated (CD14+) expression of interleukin-1alpha (IL-1alpha), IL-1beta, tumor necrosis factor-alpha (TNF-alpha), IL-8, and monocyte chemotactic protein-1 (MCP-1) after in vitro lipopolysaccharide stimulation of undiluted whole blood.

RESULTS

Calculations of partial correlation coefficients controlling for age, race, body mass index, and alcohol use indicated that BDI score was significantly associated with IL-1alpha (r = 0.27), IL-1beta (r = 0.44), TNF-alpha (r = 0.57), MCP-1 (r = 0.52), and IL-8 (r = 0.33). In addition, relative to men with BDI scores below 10, men with BDI scores of 10 or above exhibited an overexpression of IL-1beta (p =.004), TNF-alpha (p =.005), IL-8 (p =.002), and MCP-1 (p =.025).

CONCLUSIONS

Relative to men with no or minimal symptoms of depression, men with mild to moderate levels of depressive symptoms showed overexpression of monocyte-associated proinflammatory cytokines and chemokines.

Donepezil for the treatment of language deficits in adults with Down syndrome: a preliminary 24-week open trial

At present, there is no proven pharmacologic treatment for cognitive or language impairments in Down syndrome (DS). Cholinergic deficits have been documented in DS and linked to cognitive deficits. This study is a 24-week open-label clinical trial of donepezil hydrochloride for the treatment of language deficits in adults with DS. To our knowledge, this is the first prospective study to evaluate systematically the effects of donepezil, a cholinesterase inhibitor, on specific language domains in DS. The main finding that emerged was an improvement in expressive language performance following donepezil therapy. Despite the multiple methodological limitations, the results raise important questions regarding the role of the cholinergic system in language function and the specific effect of cholinergic therapy in the treatment of language impairment in DS. The results support the need for large-scale controlled studies of the effects of donepezil treatment on language and on other cognitive domains in DS.

Evidence for the treatment of borderline personality disorder

The treatment of patients with borderline personality disorder (BPD) is notoriously difficult. Psychotherapeutic and pharmacological strategies have been investigated, and a few have shown promise. Dialectical behavior therapy (DBT) may be helpful in decreasing suicidal behavior and improving symptomatology, although the data are not strong, and the actual "type" of DBT employed may influence the outcomes. Although there are a variety of studies investigating a number of different medications for the treatment of BPD, there are few randomized, double-blind, placebo-controlled trials. Furthermore, the evidence base is limited by small sample size and variability in inclusion criteria and outcome measures among the different studies. Further study is needed with larger, randomized, placebo-controlled trials to clearly demonstrate benefit of any pharmacotherapy. To date, there is suggestion from some studies that neuroleptics, carbamazepine, monoamine oxidase inhibitors, and selective serotonin reuptake inhibitors may be effective, and there is evidence that benzodiazepines are detrimental. The role of electroconvulsive therapy remains unclear.

Relationship of depression to increased risk of mortality and rehospitalization in patients with congestive heart failure

BACKGROUND

Patients with congestive heart failure (CHF) may have a high prevalence of depression, which may increase the risk of adverse outcomes.

OBJECTIVE

To determine the prevalence and relationship of depression to outcomes of patients hospitalized with CHF.

METHODS

We screened patients aged 18 years or older having New York Heart Association class II or greater CHF, an ejection fraction of 35% or less, or both, admitted between March 1, 1997, and June 30, 1998, to the cardiology service of one hospital. Patients with a Beck Depression Inventory score of 10 or higher underwent a modified National Institute of Mental Health Diagnostic Interview Schedule to identify major depressive disorder. Primary care providers coordinated standard treatment for CHF and other medical and psychiatric disorders. We assessed all-cause mortality and readmission (rehospitalization) rates 3 months and 1 year after depression assessment. Logistic regression analyses were used to evaluate the independent prognostic value of depression after adjustment for clinical risk factors.

RESULTS

Of 374 patients screened, 35.3% had a Beck Depression Inventory score of 10 or higher and 13.9% had major depressive disorder. Overall mortality was 7.9% at 3 months and 16.2% at 1 year. Major depression was associated with increased mortality at 3 months (odds ratio, 2.5 vs no depression; P =.08) and at 1 year (odds ratio, 2.23; P =.04) and readmission at 3 months (odds ratio, 1.90; P =.04) and at 1 year (odds ratio, 3.07; P =.005). These increased risks were independent of age, New York Heart Association class, baseline ejection fraction, and ischemic etiology of CHF.

CONCLUSIONS

Major depression is common in patients hospitalized with CHF and is independently associated with a poor prognosis.

MRI signal hyperintensities in geriatric depression

OBJECTIVE

The authors rated periventricular and subcortical signal hyperintensities on magnetic resonance imaging (MRI) scans in elderly patients with depression and in normal subjects with similar demographic features to examine whether such changes discriminate patients with depression from normal subjects and whether they are associated with any clinical variables.

METHOD

Two established hyperintensity rating systems were used to compare the MRI brain scans of 48 elderly patients with depression diagnosed according to DSM-III-R with the scans of 39 normal elderly subjects.

RESULTS

Elderly depressed patients manifested significantly more severe hyperintensity ratings in the subcortical gray matter than age-matched comparison subjects. Significant differences were not identified between patients with similar current ages and cerebrovascular disease risk who had early-onset or late-onset depression.

CONCLUSIONS

These findings support those of neuroimaging studies implicating the basal ganglia in depression and geriatric depression. The data suggest that the relationship observed in some reports between late-onset depression and MRI hyperintensities is most likely a function of cerebrovascular disease risk and age.

MRI changes in schizophrenia in late life: a preliminary controlled study

The aim of this pilot study was to compare cerebral changes on magnetic resonance imaging (MRI) scans in elderly schizophrenic subjects with those in psychiatric and normal control subjects. We compared the MRIs of 19 subjects with schizophrenia, 19 age- and gender-matched subjects with recurrent major depression, and 19 age- and gender-matched nonpsychiatric control subjects. Deep white matter hyperintensities (DWMH) in right posterior regions were significantly more prominent in the schizophrenic group than in the two comparison groups. Total ratings of MRI abnormalities were significantly related to age in both the normal control and schizophrenic groups, but not in the depressive group. Age of onset was positively associated with total ratings in the depressive group, but not in the schizophrenic group. Thus, a subset of elderly patients with schizophrenia appear to have cerebral white matter abnormalities; such abnormalities may not be confined to late-onset schizophrenia. Systematic MRI studies of early- and late-onset schizophrenia in late life are needed to resolve this question.

Pharmacokinetics of growth hormone secretion in humans induced by growth hormone releasing hormone

This investigation compares the age- and sex-related changes in growth hormone (GH) response to growth hormone releasing hormone (GHRH) in normal subjects using an appropriate pharmacokinetic model. Twenty-five subjects (14 males and 11 females) aged 23-89 yr received a single intravenous bolus dose (1 microgram/kg) of GHRH-40 solution. Plasma GH concentration-time profiles are best characterized by a biexponential equation (or one-compartment model) with first-order release and disappearance rates and an equilibration lag time. The harmonic mean release rate half-life is similar for both sexes (males: 12.6 min vs. females; 11.4 min) but significantly different across age groups (23-35 yr: 7.2 min vs. 50-89 yr: 16.8 min). The mean disappearance rate half-life and GHRH-equilibration time lag for females (33.6 and 20.4 min, respectively) and the higher age group subjects (32.4 and 21.6 min, respectively) are significantly longer than those of males (22.8 and 9 min, respectively) and the lower age-group subjects (21.6 and 8.4 min, respectively). The mean metabolic clearance rate of GH is significantly lower (p less than 0.02) for females than for males (3.1 vs. 4.83 ml/hr.m2). However, the production rate and the amount of GH released by the pituitary for our subjects appear to be very similar for both males (8.7 micrograms/hr.m2 and 4.65 micrograms/m2) and females (9.33 micrograms/hr.m2 and 5.11 micrograms/m2).

Marked reduction in the number of platelet-tritiated imipramine binding sites in geriatric depression

The number (Bmax) and affinity (Kd) of platelet-tritiated imipramine binding sites was determined in young and middle-aged controls 50 years of age and younger (n = 25), elderly normal controls over 60 years of age (n = 18), patients who fulfilled DSM-III criteria for major depression who were under 50 years of age (n = 29), patients who fulfilled DSM-III criteria for major depression who were 60 years of age and older (n = 19), and patients who fulfilled both DSM-III criteria for primary degenerative dementia and National Institute of Neurological and Communicative Disorders and Stroke-Alzheimer's Disease and Related Disorders Association criteria for probable Alzheimer's disease (n = 13). Both groups of depressed patients (under 50 and over 60 years of age) exhibited significant reductions (decreases 42%) in the number of platelet-tritiated imipramine binding sites with no change in affinity, when compared with their age-matched controls. There was little overlap in Bmax values between the elderly depressed patients and their controls. The patients with probable Alzheimer's disease showed no alteration in platelet-tritiated imipramine binding. There was no statistically significant relationship between postdexamethasone plasma cortisol concentrations and tritiated imipramine binding. These results indicate that platelet-tritiated imipramine binding may have potential utility as a diagnostic adjunct in geriatric depression, and moreover that the reduction in the number of platelet-tritiated imipramine binding sites is not due to hypercortisolemia.

The Newcastle Anxiety Depression Diagnostic Index in relationship to the effects of monoamine oxidase inhibitors and tricyclic antidepressants

The Newcastle Anxiety Depression Diagnostic Index (NADDI) was applied to 151 patients who received a monoamine oxidase inhibitor (MAOI) or a tricyclic antidepressant (TCA) drug. The pretreatment presence of a physical stressor and absence of agoraphobia were associated with superior MAOI effects. In women nine of the 13 NADDI items were associated with superior response to the MAOI drugs: these items comprised the absence of childhood anxiety, agoraphobia, compulsive symptoms, early awaking, and retardation, and the presence of dependent traits, neuroticism, physical stress, and panic attacks. In men the absence of suicidal tendencies and retardation, and the presence of dependent traits and panic attacks were associated with superior TCA effects. A within-treatment analysis indicated that depressed men responded better to MAOI than did anxious men.

A diagnostic and family study of posttraumatic stress disorder

A family history study of 36 patients with chronic posttraumatic stress disorder revealed a positive history of familial psychopathology in 66% of the patients. Alcoholism, depression, and anxiety disorders were the disorders most commonly found. The patients also had a higher prevalence of alcoholic siblings than did a retrospectively derived control group of depressed and anxious male patients. With respect to the proportion of familial anxiety to familial depression, the probands with posttraumatic stress disorder more closely resembled probands with generalized anxiety than probands with depression. Every patient had experienced at least one significant psychiatric illness during his lifetime, most commonly alcohol abuse or depression.

MAO inhibitor therapy in trichotillomania associated with depression: case report

Trichotillomania may sometimes be an atypical variant of depressive illness. A case is reported in which the MAO inhibitor isocarboxazid was successfully used to treat both depression and associated trichotillomania. The symptoms recurred upon discontinuation of the drug and were ameliorated by reintroduction of isocarboxazid .