Age effects on clinical and neurocognitive risk factors for suicide attempt in depression - Findings from the AFSP lifespan study

BACKGROUND

Studies of risk factors for suicidal behavior are typically restricted to narrow age ranges, making it difficult to determine if they have the same relevance or potency across the full adult lifespan.

METHODS

This study examined selected clinical and neurocognitive risk factors for suicidal behavior - borderline personality traits, aggression, depressive rumination, memory performance, and language fluency- in a multi-site sample (N = 309, ages 16-80) of depressed patients with a recent (last 5 years) suicide attempt or no history of attempt, and demographically similar non-psychiatric controls. We examined cross-sectional age and attempter/non-attempter differences on these risk factors, and whether certain risk factors were more prominent discriminators of past suicide attempt earlier or later in the lifespan. Correlations with age were computed, and logistic regression was used to classify attempter status based on each risk factor and its interaction with age.

RESULTS

Nearly all risk factors were negatively correlated with age. Borderline traits, aggression, memory, and category fluency each predicted attempter status (p < 0.05), but these effects were not different across ages. In contrast, the association between rumination and suicide attempt status differed across the lifespan, becoming a stronger discriminator of past suicidal behavior at older ages.

LIMITATIONS

The cross-sectional design limits our developmental findings.

CONCLUSIONS

Despite age-related changes in symptom severity or neurocognitive performance, key risk factors for suicidal behavior previously identified in studies with more restricted age-ranges are salient throughout the adult lifespan. In contrast, depressive rumination may be particularly salient in later life.

Influence of the GABA Receptor Subunit Gene Polymorphism and Childhood Sexual Abuse on Processing Speed in Major Depression and Suicide Attempt

Background: Suicide is moderately heritable and also more common in those who report childhood abuse. Previously, it was found that allele A of GABRG2 (GABA A receptor subunit gamma2) polymorphism rs211034 was protective in a suicide attempt (SA). Hence, it was proposed that rs211034 may interact with childhood trauma to influence cognitive deficits related to SA or depression risk. Genetic variants may predict the benefits of certain cognitive treatments. Methods: A total of 52 individuals who had attempted suicide, 59 individuals with major depressive disorder (MDD) or bipolar depression who had not previously attempted suicide, and 90 healthy volunteers were subjected to the modified Suicide Stroop task and were clinically assessed using the Childhood Trauma Questionnaire (CTQ) and Hamilton Depression Scale-24 items (HAMD-24). rs211034 was genotyped using Sanger sequencing. Results: After correcting for covariates, depressed participants displayed longer reaction times for all emotional conditions, including suicide-related words, compared with healthy controls. Depressed suicide attempters displayed longer reaction times for negative words than depressed non-attempters. Depressed non-attempters displayed higher interference scores for negative words compared with healthy controls. There was an interaction between rs211034 risk allele and the effects of reported childhood sexual abuse (CSA) on reaction time for all emotional words and suicide-related words. Carriers of the rs211034 risk allele A exhibited shorter reaction times, but the protective effects of this allele were eliminated in those exposed to reported CSA. Conclusion: Only limited results were found regarding effects of a past suicide attempt on response times to emotional and suicide-related words, but there was an overall effect of major depression on slower response time. Protective genetic effects of the rs211034 A allele on this slowing were eliminated in those with a history of sexual abuse during childhood. Further research is needed to better characterize the mechanisms underlying the effects of childhood trauma on these genetic effects.

Kappa opioid receptor binding in major depression: A pilot study

Endogenous kappa opioids mediate pathological responses to stress in animal models. However, the relationship of the kappa opioid receptor (KOR) to life stress and to psychopathology in humans is not well described. This pilot study sought, for the first time, to quantify KOR in major depressive disorder (MDD) in vivo in humans using positron emission tomography (PET). KOR binding was quantified in vivo by PET imaging with the [11 C]GR103545 radiotracer in 13 healthy volunteers and 10 participants with current MDD. We examined the relationship between regional [11 C]GR103545 total volume of distribution (VT ) and diagnosis, childhood trauma, recent life stress, and, in a subsample, salivary cortisol levels during a modified Trier Social Stress Test (mTSST), amygdala, hippocampus, ventral striatum and raphe nuclei. Whole-brain voxel-wise analyses were also performed. [11 C]GR103545 VT did not differ significantly between MDD participants and healthy volunteers in the four a priori ROIs (p = 0.50). [11 C]GR103545 VT was unrelated to reported childhood adversity (p = 0.17) or recent life stress (p = 0.56). A trend-level inverse correlation was observed between [11 C]GR103545 VT and cortisol area-under-the curve with respect to ground during the mTSST (p = 0.081). No whole-brain voxel-wise contrasts were significant. Regional [11 C]GR103545 VT , a measure of in vivo KOR binding, does not differentiate MDD from healthy volunteers in this pilot sample. Future studies may examine KOR binding in subgroups of depressed individuals at increased risk for KOR abnormalities, including co-occurring mood and substance use disorders, as well as depression with psychotic features.

White matter correlates of impaired attention control in major depressive disorder and healthy volunteers

BACKGROUND

Major depressive disorder (MDD) is associated with impaired attention control and alterations in frontal-subcortical connectivity. We hypothesized that attention control as assessed by Stroop task interference depends on white matter integrity in fronto-cingulate regions and assessed this relationship using diffusion tensor imaging (DTI) in MDD and healthy volunteers (HV).

METHODS

DTI images and Stroop task were acquired in 29 unmedicated MDD patients and 16 HVs, aged 18-65 years. The relationship between Stroop interference and fractional anisotropy (FA) was examined using region-of-interest (ROI) and tract-based spatial statistics (TBSS) analyses.

RESULTS

ROI analysis revealed that Stroop interference correlated positively with FA in left caudal anterior cingulate cortex (cACC) in HVs (r = 0.62, p = 0.01), but not in MDD (r = -0.05, p= 0.79) even after controlling for depression severity. The left cACC was among 4 ROIs in fronto-cingulate network where FA was lower in MDD relative to HVs (F_(1,41) = 8.87, p = 0.005). Additionally, TBSS showed the same group interaction of differences and correlations, although only at a statistical trend level.

LIMITATIONS

The modest sample size limits the generalizability of the findings.

CONCLUSIONS

Structural connectivity of white matter network of cACC correlated with magnitude of Stroop interference in HVs, but not MDD. The cACC-frontal network, sub-serving attention control, may be disrupted in MDD. Less cognitive control may include enhanced effects of salience in HVs, or less effective response inhibition in MDD. Further studies of salience and inhibition components of executive function may better elucidate the relationship between brain white matter changes and executive dysfunction in MDD.

Heart rate variability and suicidal behavior

Identification of biological indicators of suicide risk is important given advantages of biomarker-based models. Decreased high frequency heart rate variability (HF HRV) may be a biomarker of suicide risk. The aim of this research was to determine whether HF HRV differs between suicide attempters and non-attempters. Using the Trier Social Stress Test (TSST), we compared HF HRV between females with and without a history of suicide attempt, all with a lifetime diagnosis of a mood disorder. To investigate a potential mechanism explaining association between HF HRV and suicide, we examined the association between self-reported anger and HF HRV. Results of an Area under the Curve (AUC) analysis showed attempters had a lower cumulative HF HRV during the TSST than non-attempters. In addition, while there was no difference in self-reported anger at baseline, the increase in anger was greater in attempters, and negatively associated with HF HRV. Results suggest that suicide attempters have a reduced capacity to regulate their response to stress, and that reduced capacity to regulate anger may be a mechanism through which decreased HF HRV can lead to an increase in suicide risk. Our results have implications for the prevention of suicidal behavior in at-risk populations.

Treatment-related improvement in neuropsychological functioning in suicidal depressed patients: paroxetine vs. bupropion

Neuropsychological dysfunction is associated with risk for suicidal behavior, but it is unknown if antidepressant medication treatment is effective in reducing this dysfunction, or if specific medications might be more beneficial. A comprehensive neuropsychological battery was administered at baseline and after 8 weeks of treatment within a randomized, double-blind clinical trial comparing paroxetine and bupropion in patients with DSM-IV Major Depressive Disorder and either past suicide attempt or current suicidal thoughts. Change in neurocognitive performance was compared between assessments and between medication groups. Treatment effects on the Hamilton Depression Rating Scale and Scale for Suicide Ideation were compared with neurocognitive improvement. Neurocognitive functioning improved after treatment in all patients, without clear advantage for either medication. Improvement in memory performance was associated with a reduction in suicidal ideation independent of the improvement of depression severity. Overall, antidepressant medication improved neurocognitive performance in patients with major depression and suicide risk. Reduced suicidal ideation was best predicted by a combination of the independent improvements in both depression symptomatology and verbal memory. Targeted treatment of neurocognitive dysfunction in these patients may augment standard medication treatment for reducing suicidal behavior risk.

Familial pathways to early-onset suicide attempt: a 5.6-year prospective study

IMPORTANCE

Suicide attempts are strong predictors of suicide, a leading cause of adolescent mortality. Suicide attempts are highly familial, although the mechanisms of familial transmission are not understood. Better delineation of these mechanisms could help frame potential targets for prevention.

OBJECTIVE

To examine the mechanisms and pathways by which suicidal behavior is transmitted from parent to child.

DESIGN, SETTING, AND PARTICIPANTS

In this prospective study conducted from July 15, 1997, through June 21, 2012, a total of 701 offspring aged 10 to 50 years (mean age, 17.7 years) of 334 clinically referred probands with mood disorders, 191 (57.2%) of whom had also made a suicide attempt, were followed up for a mean of 5.6 years.

MAIN OUTCOMES AND MEASURES

The primary outcome was a suicide attempt. Variables were examined at baseline, intermediate time points, and the time point proximal to the attempt. Participants were assessed by structured psychiatric assessments and self-report and by interview measures of domains hypothesized to be related to familial transmission (eg, mood disorder and impulsive aggression).

RESULTS

Among the 701 offspring, 44 (6.3%) had made a suicide attempt before participating in the study, and 29 (4.1%) made an attempt during study follow-up. Multivariate logistic regression revealed that proband suicide attempt was a predictor of offspring suicide attempt (odds ratio [OR], 4.79; 95% CI, 1.75-13.07), even controlling for other salient offspring variables: baseline history of mood disorder (OR, 4.20; 95% CI, 1.37-12.86), baseline history of suicide attempt (OR, 5.69; 95% CI, 1.94-16.74), and mood disorder at the time point before the attempt (OR, 11.32; 95% CI, 2.29-56.00). Path analyses were consistent with these findings, revealing a direct effect of proband attempt on offspring suicide attempt, a strong effect of offspring mood disorder at each time point, and impulsive aggression as a precursor of mood disorder.

CONCLUSIONS AND RELEVANCE

Parental history of a suicide attempt conveys a nearly 5-fold increased odds of suicide attempt in offspring at risk for mood disorder, even after adjusting for the familial transmission of mood disorder. Interventions that target mood disorder and impulsive aggression in high-risk offspring may attenuate the familial transmission of suicidal behavior.

Verbal learning deficits in posttraumatic stress disorder and depression

Verbal learning and memory deficits are frequently reported in posttraumatic stress disorder (PTSD), but may be a product of its psychiatric comorbidities, especially major depressive disorder (MDD). To evaluate this hypothesis, 25 medication-free patients with PTSD and comorbid MDD were compared to 148 medication-free patients with equally severe MDD alone and to 96 nonpatients on a measure of verbal learning and memory. Additional measures of attention, working memory, and executive function were administered to evaluate their contribution to verbal memory impairment. Patients with comorbid PTSD and MDD demonstrated the greatest deficit in verbal learning compared to both MDD patients and nonpatients (omnibus effect sizes ranged d = 0.41 to 0.50), one that was not accounted for by other cognitive deficits. Findings suggest that a current diagnosis of PTSD makes a contribution to verbal learning deficits beyond the effect of depression alone.

Higher executive control and visual memory performance predict treatment completion in borderline personality disorder

BACKGROUND

Non-completion of a prescribed course of treatment occurs in 20-60% of individuals diagnosed with borderline personality disorder (BPD). While symptom severity, personality traits and environmental factors have been implicated as predictors of treatment non-completion (TNC), there have been no studies of neuropsychological predictors in this population.

METHODS

From a randomized controlled trial, a subsample of 31, unmedicated outpatients diagnosed with BPD with recent self-injurious behavior was assessed on 5 neuropsychological domains. Patients were also assessed for general IQ, demographic and other salient clinical variables. Patients were randomized to one of four treatment conditions, which lasted up to 1 year. Number of weeks in treatment (WIT) up to 1 year was utilized as the index of TNC.

RESULTS

Thirty-three percent of the subsample (n = 12) did not complete 1 year of treatment. However, more WIT were predicted by better baseline executive control (Trails B; p < 0.01) and visual memory performance (Benton visual retention; p < 0.001); other neuropsychological domains did not predict WIT.

CONCLUSION

In the treatment of outpatients with BPD, better executive control and visual memory performance predict more WIT. Assessing and addressing these neurocognitive factors in treatment may reduce TNC in this high-risk population.

Regional brain metabolic correlates of self-reported depression severity contrasted with clinician ratings

BACKGROUND

We compared brain-map correlations of relative cerebral glucose metabolism (rCMRglu) with psychopathologic factors derived from the self-rated Beck Depression Inventory (BDI) and factors from the clinician-rated Hamilton Depression Rating Scale (HDRS) factors, seeking an anatomic basis for differences in self and clinician ratings.

METHODS

[(18)F]-FDG Positron Emission Tomography generated rCMRglu, SPM-estimated, voxel-level, brain correlation maps with BDI factor scores and HDRS factor scores in medication-free major depressive disorder.

RESULTS

Regional brain correlates of BDI are more extensive than HDRS, even when adjusting for variance accounted for by the HDRS. Factors comprising the BDI were associated with distinct cortical and subcortical regions. The degree of overlap in factor correlation brain maps is explained by the variance shared by BDI and HDRS factor scores.

CONCLUSION

Self and clinician-rated aspects of depression have common and distinct neuroanatomic correlates that reflect correlations between rating scales, but correlations between glucose metabolism and self-rated depression were anatomically more extensive in this sample. Findings highlight the importance and biological underpinnings of these subjective features of major depression.

The cognitive effects of electroconvulsive therapy in community settings

Despite ongoing controversy, there has never been a large-scale, prospective study of the cognitive effects of electroconvulsive therapy (ECT). We conducted a prospective, naturalistic, longitudinal study of clinical and cognitive outcomes in patients with major depression treated at seven facilities in the New York City metropolitan area. Of 751 patients referred for ECT with a provisional diagnosis of a depressive disorder, 347 patients were eligible and participated in at least one post-ECT outcome evaluation. The primary outcome measures, Modified Mini-Mental State exam scores, delayed recall scores from the Buschke Selective Reminding Test, and retrograde amnesia scores from the Columbia University Autobiographical Memory Interview-SF (AMI-SF), were evaluated shortly following the ECT course and 6 months later. A substantial number of secondary cognitive measures were also administered. The seven sites differed significantly in cognitive outcomes both immediately and 6 months following ECT, even when controlling for patient characteristics. Electrical waveform and electrode placement had marked cognitive effects. Sine wave stimulation resulted in pronounced slowing of reaction time, both immediately and 6 months following ECT. Bilateral (BL) ECT resulted in more severe and persisting retrograde amnesia than right unilateral ECT. Advancing age, lower premorbid intellectual function, and female gender were associated with greater cognitive deficits. Thus, adverse cognitive effects were detected 6 months following the acute treatment course. Cognitive outcomes varied across treatment facilities and differences in ECT technique largely accounted for these differences. Sine wave stimulation and BL electrode placement resulted in more severe and persistent deficits.

Lifelong course of positive and negative symptoms in chronically institutionalized patients with schizophrenia

BACKGROUND

Despite widespread policies of deinstitutionalization, a substantial number of patients with schizophrenia require continuous custodial care. The hospital records of such patients provide contemporaneous documentation of symptoms throughout the illness, permitting a longitudinal study of the course of symptoms. We sought to describe this course, and to determine the influences of sex, age of onset, and treatment on its evolution.

METHODS

Using the modified Diagnostic Evaluation After Death, we performed standardized chart reviews of 99 chronic inpatients who remained in state institutions through the 1960's and 1970's and subsequently died in those institutions. Data were available from the onset of illness until death.

RESULTS

We found significant decreases in positive symptoms and increases in negative symptoms over the course of the illness. Symptom patterns were analyzed by repeated measures ANOVA. Onset before age 25 was associated with greater numbers of negative symptoms at a given age (p = 0.05). Female sex was associated with greater numbers of positive symptoms (p=0.04). The widespread introduction of neuroleptic drugs in the mid-1950's did not affect the trends in symptom patterns.

CONCLUSIONS

The lifetime course of schizophrenia in chronically institutionalized individuals is characterized by a decrease in positive symptoms and an increase in negative symptoms. Schizophrenia with earlier onset is associated with greater numbers of negative symptoms throughout life. In this sample of patients, chronically hospitalized until death, neuroleptic drugs failed to effect a persistent decrease in positive symptoms.

Symptom components of standard depression scales and past suicidal behavior

BACKGROUND

Global severity on depression scales may obscure associations between specific symptoms and suicidal behavior.

METHODS

We studied 298 persons with major depressive disorder. Factor analysis of the 24-item Hamilton Depression Rating Scale (HDRS) and the Beck Depression Inventory (BDI) was used to compare symptom clusters between past suicide attempters and non-attempters.

RESULTS

Factor analyses extracted five HDRS and three BDI factors. Suicide attempters had significantly lower scores on an HDRS anxiety factor and higher scores on a BDI self-blame factor. The factor scores correlated with total number of suicide attempts and with known risk factors for suicidal behavior.

LIMITATIONS

The differences in factor scores between suicide attempters and non-attempters were significant but modest and may be most relevant in suggesting areas for further clinical studies. Structured diagnostic interviews in this study may have limited the detection of Bipolar II or milder bipolar spectrum disorders.

CONCLUSIONS

Depressed suicide attempters exhibit comparably severe mood and neuro-vegetative symptoms, but less anxiety and more intense self-blame than non-attempters. This clinical profile may help guide studies of biological correlates and of treatments to reduce suicide risk.

Neuroanatomic correlates of psychopathologic components of major depressive disorder

BACKGROUND

The Hamilton Depression Rating Scale (HDRS) is widely used to measure the severity of depression in mood disorders. Total HDRS score correlates with brain metabolism as measured by fludeoxyglucose F 18 ([(18)F]-FDG) positron emission tomography. The HDRS comprises distinct symptom clusters that may be associated with different patterns of regional brain glucose metabolism.

OBJECTIVE

To examine associations between HDRS component psychopathologic clusters and resting glucose cerebral metabolism assessed by [(18)F]-FDG positron emission tomography. Patients We evaluated 298 drug-free patients who met the DSM-III-R criteria for major depressive disorder.

MAIN OUTCOME MEASURES

Five principal components were extracted from the 24-item HDRS for all subjects and ProMax rotated: psychic depression, loss of motivated behavior, psychosis, anxiety, and sleep disturbance. The [(18)F]-FDG scans were acquired in a subgroup of 43 drug-free patients in twelve 5-minute frames. Voxel-level correlation maps were generated with HDRS total and factor scores.

RESULTS

Total HDRS score correlated positively with activity in a large bilateral ventral cortical and subcortical region that included limbic, thalamic, and basal ganglia structures. Distinct correlation patterns were found with the 3 individual HDRS factors. Psychic depression correlated positively with metabolism in the cingulate gyrus, thalamus, and basal ganglia. Sleep disturbance correlated positively with metabolism in limbic structures and basal ganglia. Loss of motivated behavior was negatively associated with parietal and superior frontal cortical areas.

CONCLUSIONS

Different brain regions correlate with discrete symptom components that compose the overall syndrome of major depression. Future studies should extend knowledge about specific regional networks by identifying responsible neurotransmitters related to specific psychopathologic components of mood disorders.

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.

METHOD

Fifty-five subjects (25 OCD, 15 PD/A, 15 controls) without current depressive episode underwent structured clinical interview for DSM-IV, Yale-Brown Obsessive Compulsive Scale, Hamilton Anxiety Rating Scale, Hamilton Depression Rating Scale. Neuropsychological battery assessed: executive functions, visual discrimination, spatial memory and learning, verbal memory, general intellectual functioning.

RESULTS

OCD showed controlled fluency, visual-spatial construction, learning and memory deficits; PD/A spatial learning impairment. OCD was discriminated from PD/A and controls by three tests scores, predicting group membership for 76.4% of the cases.

CONCLUSION

Visual-constructive and controlled fluency deficits seem specific in OCD, while the spatial learning deficit, shared with PD patients, may not be disorder-specific, but anxiety-related. Results support the proposed ventral frontal-striatal circuit involvement in OCD.

Regional cerebral blood flow and cognitive deficits in chronic lyme disease

This study examined brain functioning in patients with Lyme encephalopathy. Eleven patients underwent neuropsychological tests and Xenon(133)-regional cerebral blood flow (rCBF) studies, using an external detector system. Each rCBF scan was age- and sex-matched to two archival, normal controls. While few differences were noted on gray-matter flow indices (ISI, fg), Lyme patients demonstrated significant flow reductions in white matter index (k(2)) (p=.004), particularly in the posterior temporal and parietal lobes bilaterally (p=.003). Flow reductions in white matter areas were significantly associated with deficits in memory (r=.66, p=.027) and visuospatial organization (r=.62, p=.041). Results suggest that Lyme encephalopathy may be a disease primarily affecting the cerebral white matter.

Positron emission tomography of regional brain metabolic responses to a serotonergic challenge and lethality of suicide attempts in major depression

BACKGROUND

Lower serotonergic activity correlates with high-lethality suicide attempts in major depression. Postmortem studies of serotonin receptors in suicides localize changes to the ventral prefrontal cortex (PFC). We studied serotonergic response in ventral PFC in depressed patients surviving a high-lethality suicide attempt.

METHODS

Depressed patients with a history of a high-lethality suicide attempt (n = 16) were compared with those with low-lethality attempts (n = 9) for level of depression, suicidal intent and ideation, impulsivity, aggression, and neuropsychological test performance. Subjects were scanned while medication free after a single-blind placebo and after fenfluramine hydrochloride administration on a second day. Brain responses were measured by positron emission tomography imaging of fludeoxyglucose F 18 and serial prolactin levels. Scans were compared by means of statistical parametric mapping. Correlations of changes in relative regional cerebral uptake (rCMRglu) with clinical and neuropsychological measures were assessed.

RESULTS

Depressed high-lethality suicide attempters had lower rCMRglu in ventral, medial, and lateral PFC compared with low-lethality attempters. This difference was more pronounced after fenfluramine administration. Lower ventromedial PFC activity was associated with lower lifetime impulsivity, higher suicidal intent (planning), and higher-lethality suicide attempts. Higher verbal fluency was positively correlated with rCMRglu in the same regions.

CONCLUSIONS

Prefrontal localized hypofunction and impaired serotonergic responsivity are proportional to the lethality of the suicide attempt and may mediate the effects of suicide intent and impulsivity on lethality. Positron emission tomographic neuroreceptor studies are needed to determine whether postmortem serotonin receptor findings are also present in vivo and contribute to the abnormal rCMRglu responses.

A controlled study of cognitive deficits in children with chronic Lyme disease

Although neurologic Lyme disease is known to cause cognitive dysfunction in adults, little is known about its long-term sequelae in children. Twenty children with a history of new-onset cognitive complaints after Lyme disease were compared with 20 matched healthy control subjects. Each child was assessed with measures of cognition and psychopathology. Children with Lyme disease had significantly more cognitive and psychiatric disturbances. Cognitive deficits were still found after controlling for anxiety, depression, and fatigue. Lyme disease in children may be accompanied by long-term neuropsychiatric disturbances, resulting in psychosocial and academic impairments. Areas for further study are discussed.

Structural abnormalities of subicular dendrites in subjects with schizophrenia and mood disorders: preliminary findings

BACKGROUND

Postmortem studies of the subiculum from subjects with schizophrenia have detected smaller pyramidal cell bodies and diminished immunoreactivity for the dendritic protein, microtubule-associated protein 2. While these findings suggest that subicular pyramidal cell dendrites may be structurally altered in subjects with schizophrenia, this possibility had not been tested directly.

METHODS

Rapid Golgi impregnation of archival brain specimens was used to compare the morphologic characteristics of subicular dendrites in subjects with schizophrenia (n = 13) and mood disorders (n = 6) with subjects without psychiatric disease (n = 8). The specimens were processed and analyzed by physicians blind to diagnosis. The extent of dendritic trees in the subiculum and fusiform gyrus was examined by Sholl analysis. Spine density on apical dendrites of subicular pyramidal cells was determined at a fixed distance from the cell body.

RESULTS

Spine density and arborization of subicular apical dendrites were significantly related to diagnostic group. Spine density was significantly lower in the schizophrenia and mood disorder groups than in the nonpsychiatric group. Among the mood disorder cases, diminished spine density was apparently related to a strong family history of major psychiatric diseases. There were no significant effects of diagnostic group on Sholl analysis of nonapical subicular dendrites nor on Sholl analysis of dendrites of neocortical pyramidal cells in the fusiform gyrus.

CONCLUSIONS

We have observed an association between schizophrenia and major mood disorders and structural abnormalities of subicular apical dendrites. Further studies are needed to test this association in a larger sample and to evaluate the potential role of family history and of confounding factors, such as medications and chronic institutionalization.

Application of cognitive scales to medical records of schizophrenia inpatients

The Scales of Cognitive Impairment Rated From Institutional Records (SCIRFIR), a battery based on commonly used dementia rating instruments, was tested on the records of 26 chronically institutionalized, elderly schizophrenia patients, for the purpose of retrospectively evaluating the long-term course of cognitive change in schizophrenia and relating it to available autopsy materials. The inter-rater reliability of the component scales was high (Intraclass Correlations = 0.78-0.96), the final item scores were comparable to ratings on living subjects, and Alzheimer-type neuropathological changes were associated with a markedly deteriorating course. The substantial potential of this method is discussed.

Senile degeneration and cognitive impairment in chronic schizophrenia

OBJECTIVE

This study was an investigation of the role of Alzheimer-type senile degenerative abnormalities in the cognitive impairment of chronic schizophrenia.

METHOD

The study group comprised 145 deceased elderly institutionalized psychiatric patients: 66 with schizophrenia, 26 with mood disorders, 36 with dementia, and 17 with other psychiatric diagnoses. The comparison group included 16 deceased elderly individuals without neurologic or psychiatric disease. Psychiatric diagnoses and cognitive status were established by standardized review of medical records. Neuritic senile plaques and neurofibrillary tangles were identified immunohistochemically and counted, by investigators blind to clinical information, in standardized regions of each brain.

RESULTS

Of the subjects with schizophrenia, 68% had definite cognitive impairment, but only 8% satisfied neuropathological criteria for Alzheimer's disease. Among the schizophrenia subjects without Alzheimer's disease, definite cognitive impairment was associated with higher levels of plaques and tangles. The schizophrenia subjects without definite cognitive impairment had fewer plaques and tangles than the unimpaired nonpsychiatric subjects.

CONCLUSIONS

Most cases of cognitive impairment in schizophrenia could not be attributed to Alzheimer's disease. An association of mild Alzheimer-type pathology with definite cognitive impairment was unique to schizophrenia. Enhanced sensitivity to the effects of aging on the brain may be a manifestation of diminished cognitive reserve in schizophrenia.

A brain imaging (single photon emission computerized tomography) study of semantic and affective processing in psychopaths

Psychopaths have been described as human predators who use charm, intimidation, and violence to control others and to satisfy their own needs. Underlying their propensity to violate social norms and expectations is a profound lack of empathy, guilt, or remorse, affective processes that have long resisted scientific investigation. Using brain imaging technology we found that psychopaths differed from nonpsychopaths in the pattern of relative cerebral blood flow during processing of emotional words. The results were consistent with the hypothesis that there are anomalies in the way psychopaths process semantic and affective information.

Blunted serotonergic responsivity in depressed inpatients

We found a 38% lower maximal prolactin response to an oral challenge dose of 60 mg of dl-fenfluramine relative to placebo in younger (< 30 years) depressed inpatients compared with the response in age-matched healthy controls (p < .03). Severity of depression did not correlate with prolactin response. Prolactin responses in older depressed patients (> or = 30 years) did not differ from older controls. Younger depressed patients differed from older depressed patients in terms of earlier age of onset of first lifetime episode of major depression, greater degree of suicidal intent during a recent suicide attempt, double the level of hopelessness on admission to hospital, and a higher rate of comorbid borderline personality disorder. A blunted prolactin response to fenfluramine may be interpreted as evidence for reduced serotonergic function in younger depressed patients and may underlie their observed greater suicidality and hopelessness.

The relationship of platelet 5-HT2 receptor indices to major depressive disorder, personality traits, and suicidal behavior

Previous research has suggested that major depression and suicidal behavior may be associated with altered serotonin receptor function. In this study, platelet serotonin2 (5-HT2) receptor binding indices were measured in conjunction with serotonin-amplified platelet aggregation, a response mediated by the platelet 5-HT2 receptor complex, in depressed patients and normal controls. The magnitude of serotonin-amplified platelet aggregation was positively correlated with the number of platelet 5-HT2 receptor sites in both groups. Mean values for the receptor binding indices and the receptor-mediated response did not differ significantly between patients and controls, although patients exhibited a wider range of values for each parameter compared with controls. Exploratory analyses were undertaken to determine clinical variables that might contribute to the increased variance in depressed individuals. These analyses failed to reveal a statistically significant relationship between any of the platelet 5-HT2 receptor measures and the subtype or severity of depressive illness, or the presence of comorbid borderline personality disorder. Although the mean number of receptor sites did not differ between patients who had recently attempted suicide and those who had never attempted suicide, a strong positive correlation (p = 0.002) was found between receptor number and the degree of medical damage resulting from the suicidal act. Furthermore, the ratio of the serotonin-amplified platelet aggregation response to platelet 5-HT2 receptor number, an index of the mean responsivity of an individual receptor complex, was lower in suicide attempters versus nonattempters (p = 0.06) and normal controls (p = 0.01). Exploratory analyses also suggested that recent exposure to psychotropic medication may result in a significant increase in platelet 5-HT2 receptor number (p = 0.03). Thus, although the study did not show a consistent alteration in platelet 5-HT2 receptor indices in major depression, the data suggest that specific factors such as suicidality and drug exposure may explain some of the variance in depressed patients.

Quinolinic acid in cerebrospinal fluid and serum in HIV-1 infection: relationship to clinical and neurological status

Quinolinic acid is an "excitotoxic" metabolite and an agonist of N-methyl-D-aspartate receptors. Of patients infected with human immunodeficiency virus type 1 (HIV-1) who were neurologically normal or exhibited only equivocal and subclinical signs of the acquired immunodeficiency syndrome (AIDS) dementia complex, concentrations of quinolinic acid in cerebrospinal fluid (CSF) were increased twofold in patients in the early stages of disease (Walter Reed stages 1 and 2) and averaged 3.8 times above normal in later-stage patients (Walter Reed stages 4 through 6). However, in patients with either clinically overt AIDS dementia complex, aseptic meningitis, opportunistic infections, or neoplasms, CSF levels were elevated over 20-fold and generally paralleled the severity of cognitive and motor dysfunction. CSF concentrations of quinolinic acid were significantly correlated to the severity of the neuropsychological deficits. After treatment of AIDS dementia complex with zidovudine and treatment of the opportunistic infections with specific antimicrobial therapies, CSF levels of quinolinic acid decreased in parallel with clinical neurological improvement. By analysis of the relationship between levels of quinolinic acid in the CSF and serum and integrity of the blood-brain barrier, as measured by the CSF:serum albumin ratio, it appears that CSF levels of quinolinic acid may be derived predominantly from intracerebral sources and perhaps from the serum. While quinolinic acid may be another "marker" of host- and virus-mediated events in the brain, the established excitotoxic effects of quinolinic acid and the magnitude of the increases in CSF levels of the acid raise the possibility that quinolinic acid plays a direct role in the pathogenesis of brain dysfunction associated with HIV-1 infection.