Negative and depressive symptoms in schizophrenia

A double-blind, randomized controlled study of the effects of celecoxib on clinical symptoms and cognitive impairment in patients with drug-naïve first episode schizophrenia: pharmacogenetic impact of cyclooxygenase-2 functional polymorphisms

Chronic low-grade peripheral and central nervous system inflammation may have a role in the pathogenesis of schizophrenia (SCZ). Inhibition of cyclooxygenase-2 (COX2), the arachidonic acid pathway, may inhibit cytokine responses and minimize inflammation. In this study, we added the COX2 inhibitor celecoxib to risperidone monotherapy to examine its efficacy on clinical symptoms and cognitive deficits in drug-naïve first episode (DNFE) SCZ patients. First, we genotyped two polymorphisms (rs5275 and rs689466) in the COX-2 gene in a case-control study of 353 SCZ patients and 422 healthy controls. Ninety patients participated in a 12-week, double-blind, randomized, placebo-controlled trial of celecoxib 400 mg/day. We used the Positive and Negative Syndrome Scale (PANSS) and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) to assess clinical symptoms and cognition. Our results show that the COX2 rs5275 polymorphism was significantly correlated with SCZ and positive symptoms. After 12-week treatment, celecoxib significantly improved the PANSS total and three subscale scores of SCZ patients. Furthermore, patients with the rs5275 TT genotype had greater improvement in PANSS total score than patients carrying the C allele. However, no significant difference in RBANS total and subscale scores existed between the celecoxib and placebo groups at week 12. Our findings suggest that COX2 inhibitors may be promising therapeutics for clinical symptoms rather than cognitive impairment in first episode SCZ patients. COX2 rs5275 gene polymorphism may be implicated in the development and the efficacy of treating clinical symptoms in SCZ.Trial Registration Number: The trial was registered with www.clinicaltrials.gov (NCT00686140).

The Relationship Between Depressive Symptoms and Psychological Variables in Patients With Schizophrenia

INTRODUCTION

Depressive symptoms are common in schizophrenia and can be seen at any stage of the disease. Although various models have been proposed to explain the development of depression in schizophrenia, studies investigating related psychological factors are scarce and the studies that have been done usually focus on only a small number of possible factors.

OBJECTIVE

The goal of this study was to investigate the predictability of some psychological factors on depression in patients with schizophrenia. For this purpose, patients with high and low depression scores were compared.

METHODS

Two groups of individuals with schizophrenia, with (n=29) and without (n=31) depression, as determined by scores on the Calgary Depression Scale in Schizophrenia, were compared using a sociodemographic data form, the Positive and Negative Syndrome Scale (PANSS), the Beck Anxiety Inventory, the Rotter Internal-External Locus 2024 of Control Scale, the Multidimensional Scale of Perceived Social Support, and the Stress Coping Styles Scale.

RESULTS

No differences were found between the 2 groups in terms of sociodemographic and clinical characteristics, social support scores, and coping styles. Statistically significant differences were found between the groups on the PANSS positive, negative, and general psychopathology subscales, in PANSS total scores, in anxiety scores, and in locus of control scores.

CONCLUSIONS

This study showed that high levels of negative, positive, and general psychopathological symptoms, external locus of control, and high anxiety scores may be predictive of depression in individuals with schizophrenia. Studies that examine psychological factors in larger patient groups may provide the opportunity to detect and target these factors earlier in the course of schizophrenia, thereby reducing morbidity and mortality.

Factors influencing the outcome of integrated therapy approach in schizophrenia: A narrative review of the literature

The integration of pharmacotherapy with psychosocial interventions has an important role to play in the improvement of functional outcome of subjects with schizophrenia (SCZ), in all stages of the disorder. It is essential for the adequate management of unmet therapeutic needs, such as negative symptoms and cognitive dysfunctions which account for most of the functional impairment of subjects with SCZ and do not respond to available antipsychotics. Enhancing the knowledge on factors involved in the effectiveness of integrated treatment plans is an important step forward for SCZ care. This review aims to identify factors that might influence the impact of integrated treatments on functional outcome. Most studies on the impact of psychosocial treatments on functional outcome of subjects with SCZ did not control for the effect of prescribed antipsychotics or concomitant medications. However, several factors relevant to ongoing pharmacological treatment might influence the outcome of integrated therapy, with an impact on the adherence to treatment (e.g., therapeutic alliance and polypharmacotherapy) or on illness-related factors addressed by the psychosocial interventions (e.g., cognitive dysfunctions or motivational deficits). Indirect evidence suggests that treatment integration should consider the possible detrimental effects of different antipsychotics or concomitant medications on cognitive functions, as well as on secondary negative symptoms. Cognitive dysfunctions can interfere with participation to an integrated treatment plan and can be worsened by extrapyramidal or metabolic side effects of antipsychotics, or concomitant treatment with anticholinergics or benzodiazepines. Secondary negative symptoms, due to positive symptoms, sedation, extrapyramidal side effects or untreated depression, might cause early drop-out and poor adherence to treatment. Researchers and clinicians should examine all the above-mentioned factors and implement appropriate and personalized integrated treatments to improve the outcome of SCZ.

Secondary Sources of Negative Symptoms in Those Meeting Criteria for a Clinical High-Risk Syndrome

BACKGROUND

Negative symptoms are diagnostic characteristics of schizophrenia. They can result from primary (i.e., idiopathic) or secondary (i.e., due to other factors such as depression, anxiety, psychosis, disorganization, medication effects) features of the illness. Although secondary sources of negative symptoms are prevalent among individuals meeting criteria for clinical high-risk syndromes that are due to high rates of comorbidity, the extent to which secondary sources account for variance in negative symptom domains is unknown. Addressing this gap is an important step in informing vulnerability models and treatments for negative symptoms. This study aimed to investigate secondary sources of negative symptoms in those meeting criteria for a clinical high-risk syndrome (N = 192).

METHODS

Simultaneous regression and hierarchical partitioning methods were used to determine the proportion of variance explained by selective serotonin reuptake inhibitor use, anxiety, depression, unusual thought content, and disorganized communication in predicting severity of five negative symptom domains (avolition, anhedonia, asociality, blunted affect, and alogia).

RESULTS

Findings revealed that depression explained the largest proportion of variance in avolition, asociality, and anhedonia. Anxiety was the most predictive of blunted affect, and selective serotonin reuptake inhibitor use explained the most variance in alogia. Analyses within male and female samples revealed that in males, depression explained a large proportion of variance in several negative symptom domains, while in females, selective serotonin reuptake inhibitor use explained variance in alogia.

CONCLUSIONS

Results highlight heterogeneity in variance explained by secondary sources of negative symptoms. These findings guide treatment development for secondary sources of negative symptoms. Furthermore, results inform etiologic models of psychosis and negative symptom conceptualizations.

What are depressive symptoms in acutely ill patients with schizophrenia spectrum disorder?

Background:

Aim was to examine depressive symptoms in acutely ill schizophrenia patients on a single symptom basis and to evaluate their relationship with positive, negative and general psychopathological symptoms.

Methods:

Two hundred and seventy-eight patients suffering from a schizophrenia spectrum disorder were analysed within a naturalistic study by the German Research Network on Schizophrenia. Using the Calgary Depression Scale for Schizophrenia (CDSS) depressive symptoms were examined and the Positive and Negative Syndrome Scale (PANSS) was applied to assess positive, negative and general symptoms. Correlation and factor analyses were calculated to detect the underlying structure and relationship of the patient’s symptoms.

Results:

The most prevalent depressive symptoms identified were depressed mood (80%), observed depression (62%) and hopelessness (54%). Thirty-nine percent of the patients suffered from depressive symptoms when applying the recommended cut-off of a CDSS total score of > 6 points at admission. Negligible correlations were found between depressive and positive symptoms as well as most PANSS negative and global symptoms despite items on depression, guilt and social withdrawal. The factor analysis revealed that the factor loading with the PANSS negative items accounted for most of the data variance followed by a factor with positive symptoms and three depression-associated factors.

Limitations:

The naturalistic study design does not allow a sufficient control of study results for the effect of different pharmacological treatments possibly influencing the appearance of depressive symptoms.

Conclusion:

Results suggest that depressive symptoms measured with the CDSS are a discrete symptom domain with only partial overlap with positive or negative symptoms.

Factor structure of the positive and negative syndrome scale (PANSS) in people at ultra high risk (UHR) for psychosis

INTRODUCTION

The Positive and Negative Syndrome Scale (PANSS), a comprehensive psychopathology assessment scale used in the evaluation of psychopathology in schizophrenia, is also often used in the Ultra-High-Risk (UHR) population. This paper examined the dimensional structure of the PANSS in a UHR sample.

METHODS

A total of 168 individuals assessed to be at UHR for psychosis on the Comprehensive Assessment of At-Risk Mental States (CAARMS) were evaluated on the PANSS, Calgary Depression Scale for Schizophrenia (CDSS), Beck Anxiety Inventory (BAI), Brief Assessment of Cognition in Schizophrenia (BACS), and Global Assessment of Functioning (GAF). Exploratory factor analysis (EFA) of the PANSS was performed to identify the factorial structure. Convergent validity was explored with the CAARMS, CDSS, BAI and BACS.

RESULTS

EFA of the PANSS yielded five symptom factors - Positive, Negative, Cognition/Disorganization, Anxiety/Depression, and Hostility. This 5-factor solution showed good convergent validity with the CAARMS composite score, CDSS, BAI, and BACS. Positive, Negative and Anxiety/Depression factors were associated with functioning.

CONCLUSION

The reported PANSS factor structure may serve to improve the understanding and measurement of clinical symptom dimensions manifested in people with UHR for future research and clinical setting.

The relationship between negative symptoms and depression in schizophrenia: a systematic review

OBJECTIVE

To provide an update on the evidence base for the nature of the relationship between negative symptoms and depressive features in people with schizophrenia, and propose new models that reflect their complex relationship.

METHOD

A systematic review following PRISMA guidelines. A total of 2210 articles were identified from EMBASE, PsychInfo and MEDLINE, and further two articles were hand-searched from references. Twenty-seven met inclusion criteria and were included in the review.

RESULTS

In schizophrenia, primary evidence suggests symptoms of low mood, suicidal ideation and pessimism have more specificity for depression whereas alogia and blunted affect may have more specificity as negative symptoms. Anhedonia, anergia and avolition may be common to both.

CONCLUSION

It may be possible to further distinguish depressive features from negative symptoms in schizophrenia when detailed phenomenology is considered. However, in a proposed dimensional model, these two domains continue to share certain phenomena, highlighting their close relationship.

Secondary negative symptoms - A review of mechanisms, assessment and treatment

Negative symptoms in schizophrenia may be classified as primary or secondary. Primary negative symptoms are thought to be intrinsic to schizophrenia, while secondary negative symptoms are caused by positive symptoms, depression, medication side-effects, social deprivation or substance abuse. Most of the research on secondary negative symptoms has aimed at ruling them out in order to isolate primary negative symptoms. However, secondary negative symptoms are common and can have a major impact on patient-relevant outcomes. Therefore, the assessment and treatment of secondary negative symptoms are clinically relevant. Furthermore, understanding the mechanisms underlying secondary negative symptoms can contribute to an integrated model of negative symptoms. In this review we provide an overview of concepts, evidence, assessment and treatment for the major causes of secondary negative symptoms. We also summarize neuroimaging research relevant to secondary negative symptoms. We emphasize the relevance of recent developments in psychopathological assessment of negative symptoms, such as the distinction between amotivation and diminished expression, which have only rarely been applied in research on secondary negative symptoms.

Relationship of depression with cognitive insight and socio-occupational outcome in patients with schizophrenia

AIM

To evaluate the prevalence of depression using different measures in patients with schizophrenia and to study the relationship of depression in schizophrenia with cognitive insight and clinical insight, disability and socio-occupational functioning.

METHODS

A total of 136 patients with schizophrenia were evaluated for depression, cognitive insight and socio-occupational functioning.

RESULTS

Of the 136 patients included in the study, one-fourth ( N = 34; 25%) were found to have depression as per the Mini International Neuropsychiatric Interview (MINI). The prevalence of depression as assessed by Calgary Depression Scale for Schizophrenia (CDSS), Hamilton depression rating scale (HDRS) and Depressive Subscale of Positive and Negative Syndrome Scale (PANSS-D) was 23.5%, 19.9% and 91.9%, respectively. Among the different scales, CDSS has highest concordance with clinician's diagnosis. Sensitivity, specificity, positive predictive value and negative predictive value for CDSS was also higher than that noted for HDRS and PANSS-D. When those with and without depression as per clinician's diagnosis were compared, those with depression were found to have significantly higher scores on Positive and Negative Syndrome Scale (PANSS) positive and general psychopathology subscales, PANSS total score, participation restriction as assessed by P-scale and had lower level of functioning as assessed by Global Assessment of Functioning (GAF). No significant difference was noted on negative symptom subscale of PANSS, clinical insight as assessed on G-12 item of PANSS, disability as assessed by Indian Disability Evaluation and Assessment Scale (IDEAS) and socio-occupational functioning as assessed by Social and Occupational Functioning Assessment Scale (SOFS). In terms of cognitive insight, those with depression had significantly higher score for both the subscales, that is, self-reflective and self-certainty subscales as well as the mean composite index score.

CONCLUSION

Our results suggest that one-fourth of patients with schizophrenia have depression, compared to HDRS and PANSS-D, CDSS has highest concordance with clinician's diagnosis of depression and presence of depression is related to cognitive insight.

Comorbid Moderate-Severe Depressive Symptoms and their Association with Quality of Life in Chinese Patients with Schizophrenia Treated in Primary Care

This study described the prevalence and correlates of comorbid moderate-severe depressive symptoms (comorbid depression thereafter) and their association with quality of life (QOL) in schizophrenia patients treated in primary care. 623 schizophrenia patients were enrolled. Patients' socio-demographic and clinical characteristics including comorbid depression [defined as a total score of 18 or above on the Montgomery-Asberg Depression Rating Scale (MADRS)] were recorded. Depressive symptoms (defined as a total score of 9 or above on the MADRS) were present in 54.1 % of patients, while 17.7 % had comorbid depression. Analysis of covariance revealed that comorbid depression was significantly associated with lower mental QOL. Multiple logistic regression analysis revealed that more severe positive and negative symptoms, anxiety symptoms, use of first-generation antipsychotics and antidepressants, were independently associated with comorbid depression. Given the negative association between comorbid depression and QOL, attempts to address comorbid depression in schizophrenia patients treated in primary care should be made.

Genetical Genomics of Behavior: A Novel Chicken Genomic Model for Anxiety Behavior

The identification of genetic variants responsible for behavioral variation is an enduring goal in biology, with wide-scale ramifications, ranging from medical research to evolutionary theory on personality syndromes. Here, we use for the first time a large-scale genetical genomics analysis in the brains of chickens to identify genes affecting anxiety as measured by an open field test. We combine quantitative trait locus (QTL) analysis in 572 individuals and expression QTL (eQTL) analysis in 129 individuals from an advanced intercross between domestic chickens and Red Junglefowl. We identify 10 putative quantitative trait genes affecting anxiety behavior. These genes were tested for an association in the mouse Heterogeneous Stock anxiety (open field) data set and human GWAS data sets for bipolar disorder, major depressive disorder, and schizophrenia. Although comparisons between species are complex, associations were observed for four of the candidate genes in mice and three of the candidate genes in humans. Using a multimodel approach we have therefore identified a number of putative quantitative trait genes affecting anxiety behavior, principally in chickens but also with some potentially translational effects as well. This study demonstrates that chickens are an excellent model organism for the genetic dissection of behavior.

Effect of perceived intimacy on social decision-making in patients with schizophrenia

Social dysfunctions including emotional perception and social decision-making are common in patients with schizophrenia. The aim of this study was to determine the level of intimacy formation and the effect of intimacy on social decision in patients with schizophrenia using virtual reality tasks, which simulate complicated social situations. Twenty-seven patients with schizophrenia and 30 healthy controls performed the 2 virtual social tasks: the intimacy task and the social decision task. The first one was to estimate repeatedly how intimate participants felt with each avatar after listening to what avatars said. The second one was to decide whether or not participants accepted the requests of easy, medium, or hard difficulty by the intimate or distant avatars. During the intimacy task, the intimacy rating scores for intimate avatars were not significantly different between groups, but those for distant avatars were significantly higher in patients than in controls. During the social decision task, the difference in the acceptance rate between intimate and distant avatars was significantly smaller in patients than in controls. In detail, a significant group difference in the acceptance rate was found only for the hard requests, but not for the easy and medium difficulty requests. These results suggest that patients with schizophrenia have a deficit in emotional perception and social decision-making. Various factors such as a peculiarity of emotional deficits, motivational deficits, concreteness, and paranoid tendency may contribute to these abnormalities.

Psychometric properties of the self-report version of the Quick Inventory of Depressive Symptoms (QIDS-SR₁₆) questionnaire in patients with schizophrenia

BACKGROUND

Self-report instruments for the assessment of depressive symptoms in patients with psychotic disorders are scarce. The Quick Inventory of Depressive Symptoms (QIDS-SR16) may be a useful self-report instrument, but has received little attention in this field. This paper aimed to test the psychometric properties of the QIDS-SR16 questionnaire in patients with a psychotic disorder.

METHODS

Patients diagnosed with a psychotic disorder from health care institutions in The Netherlands were included in the study. Depressive symptoms were assessed with the QIDS-SR16 and the Calgary Depression Scale for Schizophrenia (CDSS). Psychotic symptoms were assessed with the Positive and Negative Syndrome Scale (PANSS) and extrapyramidal symptoms (EPS) with three EPS rating scales. Spearman's correlation coefficients were used to compare the total score of the QIDS-SR16 with the total scores of the CDSS, PANSS-subscales and EPS rating scales.

RESULTS

In a sample of 621 patients with psychotic disorders, the QIDS-SR16 showed good internal consistency (α = 0.87). The QIDS-SR16 correlated moderately with the CDSS (r = 0.44) and the PANSS subscale for emotional distress (r = 0.47). The QIDS-SR16 showed weak correlation with the PANSS subscale for negative symptoms (r = 0.28) and minimal correlation with EPS rating scales (r = 0.09-0.16).

CONCLUSIONS

The QIDS-SR16 may reliably assess depressive symptoms in patients with psychotic disorders, but its concurrent validity with the CDSS was rather poor in this population. We would recommend developing a new self-report questionnaire for the assessment of depressive symptoms in patients with psychotic disorders.

The extent and origin of discordance between self- and observer-rated depression in patients with psychosis

It is assumed that patients with psychosis have difficulties indicating clinical symptoms accurately in self-reported measures. The present study investigated the ability of self-rating scales to detect symptoms of depression in patients with psychosis and aimed at identifying demographic, clinical and neurocognitive factors that predict the discordance between self-ratings and observer ratings. Inpatients and outpatients with psychosis (n=118) were assessed for depression by applying two observer rating and two self-rating scales. We found reasonable correlation scores between the ratings by patients and observers (range: r=0.50-0.57). In half of the patients (49.2%) the self-ratings corresponded well with the ratings of clinicians. Patients who rated their depressive symptoms as less severe than the clinicians demonstrated more negative symptoms such as blunted affect and poor affective rapport. Patients who rated their depression symptoms as being more severe were characterized by more self-reported general psychopathology. The concordance rates indicate that self-ratings of depression can be a valid additional tool in clinical assessment of patients with psychosis. However, clinicians should be attentive to the fact that some patients might have a general tendency to over-report symptoms and that patients with negative symptoms tend to be rated as more depressed in observer ratings compared with self-assessments.

A systematic review of instruments to measure depressive symptoms in patients with schizophrenia

BACKGROUND

Depressive symptoms require accurate recognition and monitoring in clinical practice of patients with schizophrenia. Depression instruments developed for use in depressed patients may not discriminate depressive symptoms from negative psychotic symptoms.

OBJECTIVE

We reviewed depression instruments on their reliability and validity in patients with schizophrenia.

METHODOLOGY

A systematic literature search was carried out in three electronic databases. Psychometric properties were extracted for those instruments of which reliability, divergent, concurrent and predictive validity were reported in one or more publications.

RESULTS

Forty-eight publications described the reliability and validity of six depression instruments in patients with schizophrenia. The only self-report was the Beck Depression Inventory (BDI). The Brief Psychiatric Rating Scale-Depression subscale (BPRS-D), Positive and Negative Syndrome Scale-Depression subscale (PANSS-D), Hamilton Rating Scale for Depression (HAMD), Montgomery Asberg Depression Rating Scale (MADRS) and Calgary Depression Scale for Schizophrenia (CDSS) were clinician rated. All instruments were reliable for the measurement of depressive symptoms in patients with schizophrenia. The CDSS most accurately differentiated depressive symptoms from other symptoms of schizophrenia (divergent validity), correlated well with other depression instruments (concurrent validity), and was least likely to miss cases of depression or misdiagnose depression (predictive validity).

CONCLUSIONS

We would recommend to use the CDSS for the measurement of depressive symptoms in research and in daily clinical practice of patients with schizophrenia. A valid self-report instrument is to be developed for the use in clinical practice.

Disorganization/cognitive and negative symptom dimensions in the at-risk mental state predict subsequent transition to psychosis

OBJECTIVE

The at-risk mental state (ARMS) is associated with a very high risk of psychosis, but it is difficult to predict which individuals will later develop psychosis on the basis of their presenting symptoms. We investigated psychopathological dimensions in subjects with an ARMS and examined whether particular symptom dimensions predicted subsequent transition to psychosis.

METHOD

The sample comprised 122 subjects (aged 16-35 years) meeting Personal Assessment and Crisis Evaluation clinic criteria for the ARMS recruited through Outreach and Support in South London, a clinical service for people with an ARMS. A principal axis factor analysis was performed on symptom scores, obtained at presentation from the Comprehensive Assessment of the At-Risk Mental State, using Varimax rotation. The relationship between dimension scores and transition to psychosis during the following 24 months was then examined employing Cox regression analysis.

RESULTS

Factor analysis gave rise to a 5-factor solution of negative, anxiety, disorganization/cognitive, self-harm, and manic symptom dimensions, accounting for 37% of the total variance. Scores on the negative and on the disorganization/cognitive dimensions were associated with transition to psychosis during the follow-up period (P = 0.044 and P = 0.005, respectively).

CONCLUSION

The symptoms of the ARMS have a dimensional structure similar to that evident in patients with schizophrenia except for the positive symptom dimension. The association between scores on the disorganization/cognitive and negative dimensions and later transition is consistent with independent evidence that formal thought disorder, subjective cognitive impairments, and negative symptoms are linked to the subsequent onset of psychosis.

The course of depressive symptoms and prescribing patterns of antidepressants in schizophrenia in a one-year follow-up study

BACKGROUND

Antidepressants are frequently prescribed in patients with psychotic disorders, but little is known about their effects in routine clinical practice. The objective was to investigate the prescribing patterns of antidepressants in relation to the course of depressive symptoms in patients with psychotic disorders.

METHODS

A cohort of 214 Dutch patients with psychotic disorders received two assessments of somatic and psychiatric health, including a clinician-rated screening for depressive symptoms, as part of annual routine outcome monitoring.

RESULTS

Depressive symptoms were prevalent among 43% (93) of the patients. Antidepressants were prescribed for 40% (86) of the patients and the majority 83% (71) continued this therapy after one year. Multivariable analysis showed that patients with more severe psychopathology had a higher risk to develop depressive symptoms the following year (OR [95% CI]=0.953 [0.912-0.995]). For patients with depressive symptoms at baseline, polypharmacy was a potential risk factor to keep having depressive symptoms (OR [95% CI]=1.593 [1.123-2.261]). Antidepressant use was not an independent predictor in both analyses.

CONCLUSIONS

Routine outcome monitoring in patients with psychotic disorders revealed a high prevalence of depressive symptoms. Antidepressants were frequently prescribed and continued in routine clinical practice.

The negative symptoms of schizophrenia: category or continuum?

Negative symptoms have been considered to be specific to schizophrenia or a subtype of schizophrenia: the deficit syndrome. In other words, these symptoms have been considered to be categorically different from other forms of human behavior and experience, whether they occur in healthy persons or patients with other psychiatric disorders. In this paper, we advocate a dimensional approach to negative symptoms, which is supported by two main arguments. First, enduring negative symptoms can even be observed in a variety of psychiatric disorders and they are not specific to schizophrenia. Second, we review evidence that negative symptoms show a continuous distribution from apparently healthy subjects to those with a fully developed clinical syndrome. Although the evidence does not allow for a definite decision concerning the dimensional distribution of negative symptoms, it certainly justifies exploring a dimensional approach with respect to its clinical and scientific utility. Understanding negative symptoms as a variation of normal mental processes will strengthen the development of neurocognitive models and treatment approaches.

A new nosology of psychosis and the pharmacological basis of affective and negative symptom dimensions in schizophrenia

Although first rank symptoms focus on positive symptoms of psychosis they are shared by a number of psychiatric conditions. The difficulty in differentiating bipolar disorder from schizophrenia with affective features has led to a third category of patients often loosely labeled as schizoaffective. Research in schizophrenia has attempted to render the presence or absence of negative symptoms and their relation to etiology and prognosis more explicit. A dichotomous population is a recurring theme in experimental paradigms. Thus, schizophrenia is defined as process or reactive, deficit or non-deficit and by the presence or absence of affective symptoms. Laboratory tests confirm the clinical impression showing conflicting responses to dexamethasone suppression and clearly defined differences in autonomic responsiveness, but their patho-physiological significance eludes mainstream theory. Added to this is the difficulty in agreeing to what exactly constitutes useful clinical features differentiating, for example, negative symptoms of a true deficit syndrome from features of depression. Two recent papers proposed that the general and specific cognitive features of schizophrenia and major depression result from a monoamine-cholinergic imbalance, the former due to a relative muscarinic receptor hypofunction and the latter, in contrast, to a muscarinic hypersensitivity exacerbated by monoamine depletion. Further development of these ideas will provide pharmacological principles for what is currently an incomplete and largely, descriptive nosology of psychosis. It will propose a dimensional view of affective and negative symptoms based on relative muscarinic integrity and is supported by several exciting intracellular signaling and gene expression studies. Bipolar disorder manifests both muscarinic and dopaminergic hypersensitivity. The greater the imbalance between these two receptor signaling systems, the more the clinical picture will resemble schizophrenia with bizarre, incongruent delusions and increasingly disorganized thought. The capacity for affective expression, by definition a non-deficit syndrome, will remain contingent on the degree of preservation of muscarinic signaling, which itself may be unstable and vary between trait and state examinations. At the extreme end of muscarinic impairment, a deficit schizophrenia subpopulation is proposed with a primary and fixed muscarinic receptor hypofunction.

The genomic profile of bipolar disorder and schizophrenia overlap and both have a common dopaminergic intracellular signaling which is hypersensitive to various stressors. It is proposed that the concomitant muscarinic receptor upregulation differentiates the syndromes, being marked in bipolar disorder and rather less so in schizophrenia. From a behavioral point of view non-deficit syndromes and bipolar disorder appear most proximate and could be reclassified as a spectrum of affective psychosis or schizoaffective disorders. Because of a profound malfunction of the muscarinic receptor, the deficit subgroup cannot express a comparable stress response. Nonetheless, a convergent principle of psychotic features across psychiatric disorders is a relative monoaminergic-muscarinic imbalance in signal transduction.

Rational suicide: philosophical perspectives on schizophrenia

Suicide prevention is a National Health Service priority in the United Kingdom. People with mental illness are seen to represent one of the most vulnerable groups for suicide and recent British Government policy has focused on prevention and management of perceived risk. This approach to suicide prevention is constructed under a biomedical model of psychiatry, which maintains that suicidal persons suffer from some form of disease or irrational drive towards self-destruction. Many react to the idea of self-inflicted death with instinctive revulsion, which has prevented serious discussion of the concept of rational suicide, particularly in relation to those with schizophrenia. The idea that there may be circumstances in which suicide can be viewed as rational is discussed within the biomedical approach to ethics and wider literature primarily in relation to physical disease, terminal states and chronic pain. It is not deemed a viable choice for those who are considered 'non-autonomous' due to the controlling forces of mental illness. I propose that suicide is not a consequence of mental illness per se, and that it may be seen as a rational response to a realistic perspective on the course and consequences of living with schizophrenia. The denial of dialogue about the validity of suicidal ideation for people with schizophrenia has led to negative consequences for people with serious mental illness in terms of justice and recognition of person-hood.

Psychiatric comorbidities and schizophrenia

Psychiatric comorbidities are common among patients with schizophrenia. Substance abuse comorbidity predominates. Anxiety and depressive symptoms are also very common throughout the course of illness, with an estimated prevalence of 15% for panic disorder, 29% for posttraumatic stress disorder, and 23% for obsessive-compulsive disorder. It is estimated that comorbid depression occurs in 50% of patients, and perhaps (conservatively) 47% of patients also have a lifetime diagnosis of comorbid substance abuse. This article chronicles these associations, examining whether these comorbidities are "more than chance" and might represent (distinct) phenotypes of schizophrenia. Among the anxiety disorders, the evidence at present is most abundant for an association with obsessive-compulsive disorder. Additional studies in newly diagnosed antipsychotic-naive patients and their first-degree relatives and searches for genetic and environmental risk factors are needed to replicate preliminary findings and further investigate these associations.

Patterns of stress in schizophrenia

Although it is widely recognized that stress plays a key role in the pathophysiology of schizophrenia, little is known regarding the particular types of stress patients experience. Less is known about the interplay among stressful events, personality mediators, and emotional responses. In this study, we investigated 10 stress dimensions in 29 patients with schizophrenia and 36 healthy volunteers using the Derogatis Stress Profile (DSP), and the relationship between these dimensions and symptoms in patients. Overall, patients had an approximate 0.75 standard deviation increase in stress compared with healthy volunteers. Significant increases in stress among patients compared with healthy volunteers were observed specifically in areas related to domestic environment, driven behavior, and depression, but not in health, attitude posture, time pressure, relaxation potential, role definition, hostility, or anxiety. More DSP-rated depression among patients correlated significantly with greater negative symptom severity. Patients with a shorter duration of antipsychotic drug exposure had significantly greater hostility than did patients with a longer duration of exposure, but did not differ in any other dimension. Continued investigation of domestic environmental stressors, driven behavior, and depression may be useful in identifying high-risk groups, and understanding symptom exacerbation and precipitants of relapse in patients already diagnosed with schizophrenia.

Depression in schizophrenia: methodological artifact or distinct feature of the illness?

In schizophrenia, there is a conceptual overlap between depressive and negative symptoms. This study examined the dimensional structure of depressive symptoms and their overlap with negative symptoms in a large sample of older medicated schizophrenia outpatients. Self-reported depression was obtained with the Beck Depression Inventory-II (BDI-II). Three components from this scale (i.e., dysphoria, psychosomatic and regret domains) showed excellent factorability and good consistency. However, adequate construct validity and correlates with outcomes were found for the dysphoria and regret domains, but not for the total score or the psychosomatic domain. Thus, the evaluation of domains within the BDI-II provides a more pure and clinically-relevant assessment of depressed mood in schizophrenia than the use of this scale as a whole.

Emotional processing in schizophrenia

INTRODUCTION

Persons with schizophrenia have impaired emotional processing, involving experience, expression, and recognition of emotions.

METHODS

This article reviews the historical descriptions and more recent work on emotion processing in schizophrenia.

RESULTS

Although abilities of emotional processing relate directly to interpersonal communication and psychosocial functioning, methodological issues exist in the current body of studies and resultant knowledge, which limit translation to novel treatment options.

CONCLUSIONS

Further improvement in emotion processing in persons with stable schizophrenia are unlikely to result from conventional pharmacotherapy of psychosis. New treatment modalities and behavioural interventions offer possible improvements in quality of life and psychosocial functioning.

Anhedonia in schizophrenia: a review of assessment strategies

Anhedonia, the diminished capacity to experience pleasant emotions, is a common, treatment-resistant feature of schizophrenia that is often included among the negative symptoms of this disorder. This selective review describes the 3 most commonly used approaches to assess anhedonia in schizophrenia: interview-based measures, self-report trait questionnaires, and laboratory-based assessments of emotional experience. For each assessment approach, psychometric properties, relationships to other symptoms and features of schizophrenia, and relationships with the other assessment approaches are evaluated. It is concluded that anhedonia can be reliably assessed and constitutes a distinctive, clinically important aspect of schizophrenia that should be included in a comprehensive evaluation of negative symptoms. Current efforts to define more precisely the nature of the hedonic deficit in schizophrenia are discussed, and recommendations for optimal assessment of anhedonia in clinical trials of novel treatments for negative symptoms are provided.

Depressive and negative symptoms in schizophrenia: different effects on clinical features

OBJECTIVE

The primary aim of this study was to investigate whether depressive symptoms were significantly associated with functional outcome measures in a clinically stable group of outpatients with schizophrenia. We also analyzed whether depressive and negative symptoms presented different patterns of predictors.

METHOD

Seventy-eight consecutive outpatients meeting Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria for schizophrenia in the stable period were enrolled in this cross-sectional study. Assessment were performed using the Calgary Depression Scale for Schizophrenia, Positive and Negative Syndromes Scale (PANSS), Clinical Global Impression Scale-severity, Social and Occupational Functioning Assessment Scale, Sheehan Disability Scale, and Quality of Life Scale. A neuropsychologic battery including the vocabulary and block design subtests of the Wechsler Adult Intelligence Scale-Revised, Wechsler Memory Scale, Wisconsin Card Sorting Test, and Continuous Performance Test was also administered to the patients. Two multiple regressions were performed testing demographic and clinical factors, rating scales, and cognitive measures as independent variables and Calgary Depression Scale for Schizophrenia and PANSS-negative subscale scores as dependent variables.

RESULTS

Four variables were predictors of depressive symptoms in our sample of schizophrenic patients: 2 outcome measures (Sheehan Disability Scale and Quality of Life Scale), gender, and Continuous Performance Test reaction time. Predictors of negative symptoms were the measures of severity of psychopathology (Clinical Global Impression Scale-severity and PANSS-general psychopathology subscale) and the cognitive tests Wechsler Adult Intelligence Scale-Revised block design and Wechsler Memory Scale.

CONCLUSION

We found that depressive symptoms in schizophrenia are mainly a function of the level of social adjustment and quality of life, whereas negative symptoms constitute an indicator of severity of schizophrenia. The 2 symptom dimensions showed also distinct cognitive correlates.

The demystification of autoscopic phenomena: experimental propositions

Autoscopic phenomena (AP) are rare, illusory visual experiences during which the subject has the impression of seeing a second own body in extrapersonal space. AP consist of out-of-body experience, autoscopic hallucination, and heautoscopy. Recent neurologic reports support the role of multisensory integration deficits of body-related information and vestibular dysfunctions in AP at the temporo-parietal junction. A caveat to test the underlying neurologic and cognitive mechanisms of AP has been their rare and spontaneous occurrence. Recent evidence linked AP to mental own-body imagery engaging brain mechanisms at the temporo-parietal junction. These recent observations open a new avenue for testing AP-related cognitive mechanisms in selected clinical and normal populations. We review evidence on several clinical syndromes (psychosis, depression, anxiety, depersonalization, body dysmorphic disorder), suggesting that some of these syndromes may relate to AP-proneness, thereby leading to testable propositions for future research on body and self processing in addition to AP.

Depressive syndrome in major psychoses: a study on 1351 subjects

The aim of this study was to investigate depressive symptomatology across distinct major psychiatric disorders. A total of 1351 subjects affected by major depressive disorder (MDD = 389), bipolar disorder (BP = 511), delusional disorder (DD = 93) and schizophrenia (SKZ = 358) were included in our study. Subjects were assessed using the Operational Criteria for Psychotic Illness checklist (OPCRIT). The most frequently represented depressive symptoms in MDD were Loss of energy/tiredness, Loss of pleasure, Poor concentration, and Sleep disorders. Compared with MDD, BP had higher occurrences of Agitated activity, Excessive sleep, and Increased appetite and/or Weight gain, as well as lower Loss of pleasure. In our sample, 32.3% and 26.8% of DD and SKZ, respectively, had quite consistent depressive symptomatology, with at least four or more depressive symptoms. The most common depressive symptoms were Sleep disorders, Poor concentration and Loss of energy/Tiredness, followed by Psychomotor symptoms in SKZ only. Excessive self-reproach, Suicidal ideation, and Appetite and/or Weight changes were more specific to mood disorders. Finally, compared with SKZ, DD suffered from more depressive symptoms and had more severe depressive symptomatology. A quite consistent level of depressive symptomatology is therefore present in subpopulations of delusional and schizophrenic subjects other than in affective subjects. We identified some symptoms that are common across all major psychoses and symptoms that are more specific to each group.

Possible Relationship Between Testosterone and Comorbid Major Depressive Episode in Male Patients With Schizophrenia Treated With Typical Antipsychotic Medications

In this cross-sectional study, the author tested the hypothesis that serum testosterone levels were associated with depressive illness in chronic male schizophrenia patients. The subjects were 49 male inpatients meeting DSM-IV criteria for schizophrenia treated with typical antipsychotic medications. The author found that the schizophrenia patients with major depressive episodes (MDE) had been taking significantly higher dosages of antipsychotic medications than those without an MDE. Also, there was a trend for the serum testosterone concentration to be lower in schizophrenia patients with an MDE. It is suggested that we should be aware of testosterone levels when we find depression in chronic male schizophrenia patients, especially those treated with high-dose typical antipsychotic medications.

Selective serotonin reuptake inhibitor augmentation in the treatment of negative symptoms of schizophrenia

The treatment of negative symptoms of schizophrenia presents a major clinical challenge. This review examines the evidence pertaining to the efficacy, tolerability and safety of adding selective serotonin reuptake inhibitors (SSRIs) to antipsychotic agents in the treatment of negative symptoms in schizophrenia. Important methodological issues such as differentiating primary and secondary negative symptoms are discussed. The balance of available evidence indicates that at least some SSRIs, fluvoxamine and fluoxetine, can ameliorate primary negative symptoms in chronic schizophrenia patients who are treated with typical antipsychotics. The combination is safe and well tolerated although, as antipsychotic drug concentrations may be elevated, attention to dose and drug monitoring should be considered as appropriate. The effect of SSRI augmentation of atypical antipsychotics requires further study. Combination with clozapine may require particular caution because of potential toxicity if serum clozapine levels rise steeply. SSRI augmentation may be a useful addition to the treatment of schizophrenia.

Influence of depressive symptoms and premorbid adjustment on factor structure of phenomenology of schizophrenia: a study from India

This study investigated the nature of factor structure of schizophrenia syndromes using a sample of 151 patients with schizophrenia according to DSM-IV. The patients were assessed on the Scale for the Assessment of Positive Symptoms (SAPS), the Scale for the Assessment of Negative Symptoms (SANS), Hamilton Depression Rating Scale (HDRS) and the Phillips Rating Scale of Premorbid Adjustment in schizophrenia. Three factors-negative syndrome, reality-distortion syndrome and disorganized syndrome were extracted when only SAPS and SANS were analysed. Addition of the Phillips Rating Scale scores to SAPS and SANS ratings in the factorial equation led to splitting of the negative syndrome though reality-distortion and disorganized syndromes remained stable. Factor analysis of the HDRS scores with SAPS and SANS ratings resulted in the HDRS loading highly on reality-distortion syndrome and splitting of negative syndrome. Factor analysis of all the variables taken together resulted in delineation of four factors. The study suggests a link between depression and reality distortion. Apathy and anhedonia seem to be linked to premorbid adjustment.

Depressive symptoms in chronic schizophrenia patients: any differences between patients with and without a major depressive episode?

The author investigated the differences between schizophrenia patients with and without a major depressive episode (MDE) using the Japanese Calgary Depression Scale for Schizophrenics. The total depression score was correlated with the dosage of antipsychotics in patients without an MDE, but such a correlation was not found in patients with an MDE.

Postpsychotic depression in schizophrenia patients

Depression is a frequent comorbidity in the course of schizophrenia and is associated with increased mortality from suicide. Postpsychotic depression is defined as the syndrome of major depression occurring following remission of psychotic symptoms in a person with schizophrenia. Various proposed causes, differential diagnosis, and issues regarding management of postpsychotic depression are discussed.

Depressive, positive, negative and parkinsonian symptomsin schizophrenia

OBJECTIVE

Depressive symptoms are common in schizophrenia but their relationship to the positive and negative symptoms of the disorder and to extrapyramidal side-effects remains unclear. Considerable overlap exists between these symptom clusters when rated with traditional clinical rating scales. The aim of this study was to investigate the relationship of depressive to positive, negative and parkinsonian symptoms using the recent adaptation of the Positive and Negative Syndrome Scale (PANSS).

METHOD

The study involved the cross-sectional measurement of symptoms in a sample of community-treated and hospitalized patients with schizophrenia. Structured assessment included thePANSS, Montgomery-Asberg Depression Rating Scale (MADRS) and the Extrapyramidal Side Effects Rating Scale (ESRS).

RESULTS

Depressive symptoms were common and correlated with positive and negative symptoms. These correlations were of a similar magnitude using either the original PANSS factor structure or the newer pentagonal model. The overlap between depressive and negative symptoms was limited to certain items in the rating scales and there was a clear separation between these symptom clusters and the other items. Parkinsonian symptoms also correlated with negative symptoms rated with either PANSS model.

CONCLUSION

Use of the pentagonal PANSS model does not improve its capacity to distinguish between depressive and negative symptoms. Positive, negative, parkinsonian and depressive symptoms overlap using common rating scales but there appears to be some separation between these symptom domains when rated with individual scale items rather than total scale scores.

Anhedonia in depression and schizophrenia: a reexamination

The purpose of this study was to utilize factor analysis to help determine whether anhedonia is a symptom of both depression and schizophrenia. Measures of depression, positive and negative symptoms of schizophrenia, and anhedonia were administered to a group of schizophrenic patients (N = 54) and to a group of patients with major depressive disorder (N = 27). The correlation matrix among the various scales was subjected to an oblique exploratory factor analysis. Three factors were extracted, accounting for three quarters of the variance. The first measured depression, the second measured positive symptoms, and the third measured negative symptoms. Anhedonia loaded significantly on the first factor but not on the third, suggesting that it is a symptom of depression rather than schizophrenia. These results were corroborated by means of confirmatory factor analysis. We conclude that anhedonia is a symptom of depression and that it only appears to be a symptom of schizophrenia because it is a component of emotional blunting which is indeed a negative symptom of schizophrenia.

Fluvoxamine as an adjunctive agent in schizophrenia

Schizophrenia is a common mental disorder that has an early onset and rates high as a cause of medical disability. Antipsychotic agents are the mainstay of treatment but response is often inadequate. Negative symptoms (disturbances in volition, social interaction and affective functions) are particularly difficult to treat and form a major obstacle to rehabilitation. A promising approach to improve response of negative symptoms has been to add a selective serotonin reuptake inhibitor (SSRI) antidepressant to antipsychotic treatment. This review examines evidence pertaining to the efficacy, tolerability, and safety of the SSRI fluvoxamine, combined with antipsychotic agents, in the treatment of negative symptoms in schizophrenia. Important methodological issues, such as differentiating primary and secondary negative symptoms, are discussed. The balance of available evidence indicates that fluvoxamine can improve primary negative symptoms in chronic schizophrenia patients treated with typical antipsychotics and suggests that it may also do so in some patients treated with clozapine. This combination is generally safe and well tolerated although, as antipsychotic drug concentrations may be elevated, attention to dose and drug monitoring should be considered appropriately. Combination with clozapine may require particular caution because of potential toxicity if serum clozapine levels rise steeply. The fluvoxamine doses effective in augmentation are lower than those usually used to treat depression. Evidence regarding the use of fluvoxamine augmentation to treat phenomena, such as obsessions and aggression, which may be associated with schizophrenia, is also examined. An important goal of future studies will be to define which patient groups can benefit from combined treatment.

Quality of life in schizophrenia: contributions of anxiety and depression

A number of studies have demonstrated a strong relationship between quality of life in schizophrenia and general psychopathology measures, and moreover, that the positive, negative, and disorganized symptoms are less related to quality of life. The current investigation examined the relationship between quality of life and symptomatology in 63 stabilized outpatients diagnosed with schizophrenia or schizoaffective disorder. Consistent with other findings, more severe depression, as rated on the Brief Psychiatric Rating Scale (BPRS) was associated with lower general life satisfaction and lower satisfaction with daily living, finances, health, and social life. In addition, higher anxiety ratings on the BPRS were associated with less satisfaction with global quality of life, daily activities, family, health and social relationship, even when controlling for positive symptoms, negative symptoms, or depression. No other symptoms of schizophrenia were as strongly associated with subjective quality of life. Anxiety was also significantly correlated with a number of positive and negative symptoms while depression was substantially less related. These findings, suggest that more precise analyses of general psychopathology, and anxiety in particular, may be necessary to further clarify the factors involved in quality of life in schizophrenia. In addition, these findings suggest future directions for theories of affect and treatment in schizophrenia.

Depressive symptoms in stable chronic schizophrenia: prevalence and relationship to psychopathology and treatment

The prevalence and correlates of the depressive syndrome were explored in a population of 120 patients with stable, chronic schizophrenia living in the community. The presence of clinically significant depressive symptoms was defined by a score of 17 or greater on the Beck Depression Inventory. Patients were examined to assess severity of schizophrenic symptoms and medication side-effects. Sixteen of the 120 patients (13.3%) had significant depressive symptoms. Depressive symptoms were significantly correlated with the hostility/suspiciousness (P<0.0001), the positive symptom (P=0.0009) factor of the BPRS and with scores on the Significant Others Scale, a measure of patients' perceived lack of social support (P=0.0004). The association between depression and akathisia approached significance (P=0.007). There was no correlation with demographic variables, alcohol intake, antipsychotic dosage or anticholinergic dosage. Using a scale that rates the subjective aspects of the depressive syndrome, we found no evidence of a relationship between depression and negative symptoms in this population. These results indicate that persistent depressive symptoms in stable patients in the community are related to the degree of persistent positive psychotic symptoms, patient perceptions of social support and, weakly, to the degree of akathisia but not other aspects of antipsychotic treatment.

Depression Scale (DEPS) in schizophrenia

OBJECTIVE

To explore the applicability of the Depression Scale (DEPS), a screening instrument for detecting depression in primary health care, in schizophrenia.

METHOD

The DEPS was compared with the Calgary Depression Scale (CDS) among 63 patients with schizophrenia.

RESULTS

Using the CDS as a gold standard, the positive and negative predictive values of the DEPS for the diagnosis of depression were 41% and 97%, respectively. The correlation between the total CDS scores and the total DEPS scores was 0.73.

CONCLUSION

The DEPS appears to be useful for screening depression among schizophrenic patients, but the positive diagnosis must be confirmed with a clinical interview.

Positive and negative symptoms and and adjustment in severely mentally ill outpatients

Studying the relationships among clinical symptoms and adjustment can clarify prognostic factors in severe mental disorders, highlight syndromes that may be the focus of different treatments, and illuminate causal relationships connecting premorbid, 'acute', and long-term psychopathological features. This article examines the relationship between positive and negative symptoms and community adjustment in 398 community mental health center outpatients maintained on neuroleptic medication. Outcome measures include psychiatric hospitalization, employment, and social involvement. Affective symptomatology, premorbid social competence, and three neuropsychological measures are additional independent variables. Positive and negative symptoms are significantly correlated with separate aspects of contemporaneous adjustment, as well as with subsequent hospitalization. Negative symptoms are predominantly related to prior hospitalization, employment, and social interactions; positive symptoms are primarily related to subsequent hospitalization. Disordered attention is most related to global neuropsychological impairment; avolition is mainly associated with degree of employment. Findings are separable from the effects of schizophrenic vs. non-schizophrenic diagnosis. Special attention is paid to a central group of negative symptoms, to separating negative symptoms from neuropsychological deficits, and to distinguishing premorbid from current social functioning.

Depressive symptoms and schizophrenic relapses: the effect of four neuroleptic drugs

1. A prevalence of depressive symptomatology, ranging from 25% to 80% has been reported during the course of schizophrenia. 2. Depressive symptoms were assessed in 144 schizophrenic patients (DSM IV) during an acute exacerbation phase. 3. Depressive symptoms showed a prevalence ranging from 5.5% (severe clinical pictures) to 54.8 (mild clinical pictures). 4. The authors did not find a correlation between depressive symptoms per se and the presence of negative psychotic symptoms. Depression may be linked not so much to negative symptoms but to the psychotic state itself. 5. Depressive symptomatology concurrently occurred with schizophrenic relapses and improved together with the psychotic clinical picture, independently of the neuroleptic drug employed. Haloperidol, haloperidol decanoate and fluphenazine decanoate all showed a similar improvement of depressive symptoms. 6. L-sulpiride showed a trend to be most effective on depressive symptomatology in comparison to the other neuroleptics.

The structure of schizophrenic symptoms: a meta-analytic confirmatory factor analysis

To quantitatively review all presently available evidence about the interrelations between positive and negative schizophrenic symptoms, we created an aggregate matrix of the intercorrelations among schizophrenic symptoms by combining data from 28 independent samples using meta-analytic procedures (net bivariate dfs ranging from 683 to 1657). Using confirmatory factor analyses, we then statistically compared four theoretically derived models of the structure of schizophrenic symptoms. Although a three-factor model (Liddle, 1987) best fit the data, results suggest that either more factors or different symptoms are required to account well for the latent structure underlying schizophrenic symptomatology. The nature of such augmented approaches, the opportunities and constraints inherent to multifactorial models, and the limitations of current instruments are discussed.

Depression in schizophrenia: I. Association with neuropsychological deficits

BACKGROUND

The presence of depression in schizophrenia has been well described with regard to stage and symptoms of illness; however, little is known about the possible etiology.

METHODS

In an effort to advance the understanding of the neurobiology of depression in schizophrenia, we grouped patients with schizophrenia based on their ratings on the 21-item Hamilton Depression Rating Scale. There were 63 patients (35 men, 28 women) in the high (> or = 18) depression group and 81 patients (52 men, 29 women) in the low (< 18) depression group. The groups were compared in demographic, clinical, and eight neuropsychological domains.

RESULTS

The two groups differed in age at onset of illness, severity of delusions, and performance in a single neuropsychological domain: attention. The specific component of impaired attention was vigilance, with poorest performance seen in women with higher depression scores.

CONCLUSION

The presence of specific attentional impairment associated with depressive symptoms in schizophrenia is consistent with the hypothesis of frontal lobe dysfunction in depression, because these regions have been implicated in attentional processes.

Factor structure of symptoms in functional psychoses

Global ratings from the Scale for the Assessment of Positive Symptoms and Scale for the Assessment of Negative Symptoms were subjected to principal-component analysis (PCA) in 80 schizophrenia patients, 76 patients with schizophreniform disorder, 80 patients with schizoaffective and mood disorders, and 78 patients with delusional, brief reactive, and atypical psychoses. The resulting factors were correlated with depressive, manic, and catatonic syndromes, and subjected to a multivariate analysis of variance across DSM-III-R diagnoses. PCAs revealed that psychosis, disorganization, and negative factors were also present in each of the nonschizophrenic groups. The disorganization factor tended to be related to the manic syndrome, and the negative factor to depressive and catatonic syndromes. Overall, the three factors had little diagnostic relevance in functional psychoses, although the negative factor was relatively more characteristic of schizophrenia. The data suggest that positive, negative, and disorganization factors are not specific to schizophrenia; this is consistent with a dimensional view of psychopathology in functional psychoses.

Depressive symptoms in acute schizophrenic inpatients

Prospective and longitudinal assessment of depressive, positive, and negative symptoms were performed on 86 newly admitted schizophrenic patients. The improvement of depressive symptoms was significantly correlated with the improvement in positive symptoms, but did not correlate with the improvement in negative symptoms. However, depressive symptoms were heterogeneous. Principal components analysis was used to subdivide depressive symptoms into five factors. The improvement of the depression-anxiety factor was significantly associated with improvement of positive symptoms. On the other hand, improvement of negative symptoms was significantly related to that of the reduced activity factor. The change in hypochondriasis had a significant positive correlation with the change in positive symptoms and had a significant negative correlation with the change in negative symptoms. Changes in the other factors of depressive symptoms did not appear to be associated with changes in positive or negative symptoms. The present findings suggest that the various depressive symptoms associated with acute schizophrenia may have different pathophysiological origins.

Construct validity of negative symptoms: an empirical and conceptual review

The construct validity of negative symptoms is reviewed, and findings on deficit negative symptoms are also incorporated. A valid negative symptom construct should: (a) have replicable relationships with observable phenomena and other constructs; (b) have good reliability, temporal stability, and homogeneity; and (c) predict prognosis and response to treatment, possess convergent and discriminant validity, and be useful to clinicians. Although a number of well-replicated findings provide support for the validity of the construct, modification is warranted. Specifically, the data suggest that there is a highly correlated set of negative symptoms, which includes flat affect, alogia, anhedonia, and avolition. Primary and enduring symptoms from this set have good predictive and discriminant validity and can be studied in the context of the deficit syndrome, as well as with current negative symptom rating scales. Future studies should examine whether deficit negative symptoms are better conceptualized as a dimension or a category, elucidate the relationship between deficit symptoms and additional clinical and behavioral variables (e.g., response to newer neuroleptic medications and diminished emotional responding), and explore differences between the pattern of correlates of deficit symptoms and those of the positive and thought disorder symptoms.

Depression in schizophrenia: a comparison of three measures

Depression, as a feature of schizophrenia, is well established. However, clarifying the exact nature of this relationship has been problematic. The clinical measures routinely utilized to evaluate depression have not been specifically designed for use in schizophrenia, and it is well recognized that a variety of depressive symptoms overlap with other features common to this illness, e.g. negative symptoms, neuroleptic induced side effects. The present study compared three commonly used measures of depression (Hamilton Depression Rating Scale (Ham-D), Calgary Depression Scale (CDS) and the depression subscale of the Positive and Negative Syndrome scale (PANSS-D) in a group of outpatients with schizophrenia, evaluating the degree of association between the scales. Additionally, the relationship between each of the depression measures, negative symptoms and extrapyramidal symptoms (EPS) was calculated. Results revealed that all three measures of depression were significantly correlated, although the CDS was unique in its ability to distinguish between depression, negative symptoms and EPS. It is concluded that the CDS, when compared with the HAM-D and the PANSS-D, is the most suitable measure of depression in schizophrenia.

A study of the interrelationship between and comparative interrater reliability of the SAPS, SANS and PANSS

We assessed the comparative interrater reliability of the SANS/SAPS and PANSS as measures of symptomatology in schizophrenia and also examined the interrelationship between scores on these instruments. Two experienced raters used these Scales to assess positive and negative symptoms in a group of 85 patients with a DSM III-R diagnosis of schizophrenia. Ratings were based on structured clinical interviews, review of case notes and consultation with staff familiar with the patients. Comparable levels of interrater reliability were found for each system of measuring symptomatology, but levels of interrater reliability were on the whole lower than have been reported in the past. There were high correlations between overall indices of positive and negative symptomatology derived from the two measurement systems.

Negative symptoms and affective disturbance in schizophrenia and related disorders

OBJECTIVE

To review the data and discuss clinical recommendations for treating negative symptoms of schizophrenia. Negative symptoms (e.g., poverty of thought, affective blunting) have been regarded as part of schizophrenia since Kraepelin's early descriptions, although they remain a subject of controversy. For example, it is unclear if negative symptoms are distinct from other psychiatric symptoms such as depression, or are in actuality depression within schizophrenia. Recent evidence suggests that negative symptoms are independent of depression.

METHOD

Factor analytic studies have suggested that a negative factor (loss of affect, volition, poverty of thinking) may be distinguished from other components and is separable from a depression factor. Experimental use of vignettes have also been useful in the assessment of negative symptoms. A second controversial area is whether or not the presence or absence of affect is the fundamental issue separating schizophrenia from other psychoses.

RESULTS

A continuum of psychosis has been hypothesized, with unipolar psychotic depression at one pole and schizophrenia with defect state at the other. Within this proposed continuum, negative symptoms are associated only with schizophrenia without affect and with defect state schizophrenia. As such, variation in affect could be a primary determinant of the type of psychosis.

CONCLUSION

It appears that negative symptoms are a distinct aspect of schizophrenia and may aid in our understanding of psychotic disorders.