Recognising psychiatric symptoms. Relevance to the diagnostic process

Resident training in psychopathology and uncertainty in a clinical situation

The central theme of this article is the way in which psychiatry physicians-in-training deal with uncertainty in the discussion of clinical cases in Mexico. Methodologically, it is approached from the field of clinical ethnography and the narrative interpretation of plots in performative actions where there are sequences of communicative exchanges. In this way, it focuses on a detailed description of situations where clinical cases are reviewed to decipher, explain, and understand intersubjective meanings in the face of the emergence of uncertainty, its management, and the implications on decisions and actions. The study finds that limitations within the field of psychiatry lie in the nosographic construction of disease and its translation into the diagnostic hypotheses made by clinicians, where there are wide margins of ambiguity. The strategies implemented in the face of uncertainty are use of drugs, the collegiate review of the case, and utilization of intuition as a spontaneous, preconscious daily practice. The specific case described here provides a microscopic observation of the complex scenarios in which uncertainty occurs in educational and teaching processes, clearly revealing how patient care is articulated. The narratives and their interpretation are materials for training/curriculum and psychiatric clinical practice.

Dynamical systems in computational psychiatry: A toy-model to apprehend the dynamics of psychiatric symptoms

Introduction

These last years, scientific research focuses on the dynamical aspects of psychiatric disorders and their clinical significance. In this article, we proposed a theoretical framework formalized as a generic mathematical model capturing the heterogeneous individual evolutions of psychiatric symptoms. The first goal of this computational model based on differential equations is to illustrate the nonlinear dynamics of psychiatric symptoms. It offers an original approach to nonlinear dynamics to clinical psychiatrists.

Methods

In this study, we propose a 3+1 dimensions model (x, y, z + f) reproducing the clinical observations encountered in clinical psychiatry with: a variable modeling environmental noise (z) on the patient's internal factors (y) with its temporal specificities (f) and symptomatology (x). This toy-model is able to integrate empirical or simulated data from the influence of perceived environmental over time, their potential importance on the internal and subjective patient-specific elements, and their interaction with the apparent intensity of symptoms.

Results

Constrained by clinical observation of case formulations, the dynamics of psychiatric symptoms is studied through four main psychiatric conditions were modeled: i) a healthy situation, ii) a kind of psychiatric disorder evolving following an outbreak (i.e., schizophrenia spectrum), iii) a kind of psychiatric disorder evolving by kindling and bursts (e.g., bipolar and related disorders); iv) and a kind of psychiatric disorder evolving due to its high susceptibility to the environment (e.g., spersistent complex bereavement disorder). Moreover, we simulate the action of treatments on different psychiatric conditions.

Discussion

We show that the challenges of dynamical systems allow to understand the interactions of psychiatric symptoms with environmental, descriptive, subjective or biological variables. Although this non-linear dynamical model has limitations (e.g., explanatory scope or discriminant validity), simulations provide at least five main interests for clinical psychiatry, such as a visualization of the potential different evolution of psychiatric disorders, formulation of clinical cases, information about attracting states and bifurcations, or the possibility of a nosological refinement of psychiatric models (e.g., staging and symptom network models).

Clinical & diagnostic issues in catatonia

The concept of catatonia was formulated in the 1860s by Karl Ludwig Kahlbaum. He coined and gave the name catatonia to the syndromic entity in which the mood symptoms (depression and mania) were primary, and motor symptoms (mutism, negativism, stereotypies, catalepsy and verbigeration) the most characteristic. Although the name has remained stable, this concept has changed in the last century concerning the details of its definition until the current integrative approach in DSM 5. Catatonic phenomena are main components of the ‘motor abnormalities’ domain in psychiatric, neurologic and general medical disorders and they have to be evaluated in the context of a full psychopatological and neurological examination. In this article, we make a review about clinical and diagnostic issues in catatonia. Catatonic phenomena comprise both state and trait characteristics and have prognostic validity in psychosis. Moreover, providing that motor abnormalities are closer to neurobiological underpinnings than other psychotic symptoms (e.g., positive symptoms of schizophrenia), catatonic phenomena should be studied specifically as targets for neurobiological research.

Development of a clinician-administered National Institutes of Health-Brief Fatigue Inventory: A measure of fatigue in the context of depressive disorders

OBJECTIVE

Fatigue is a complex, multidimensional condition. Although it is often associated with depression, it is not known whether it has a distinct network from depression or whether it can be clinically evaluated, separately. This study describes preliminary findings in the development of a brief, clinician-administered instrument to measure fatigue in the context of depressive disorders using items from existing clinician-administered depression and mania scales.

METHODS

Based on items from prior fatigue measurements, items were selected from the Hamilton Depression Rating Scale (HDRS), Montgomery-Asberg Depression Rating Scale (MADRS), Young Mania Rating Scale, and Structured Interview Guide for HDRS with Atypical Depression. The final items composed the NIH-Brief Fatigue Inventory (NIH-BFI). Responses from 89 depressed adults collected pre- and post-antidepressant therapy (ADT) determined the reliability and consistency of the NIH-BFI using Cronbach's alpha and principal components analysis (PCA). Correlations of the NIH-BFI and fatigue items from other scales before and after ADT explored validity.

RESULTS

The 7-item NIH-BFI had Cronbach alphas ranging from 0.81 to 0.88 and PCA indicating a single dimension. The NIH-BFI score was strongly correlated (r = 0.73, p < 0.001) with fatigue items from Beck Depression Index, with MADRS without fatigue items (r = 0.77, p < 0.001), and HDRS without fatigue items (pre: r = 0.69, p < 0.001).

CONCLUSIONS

Preliminary findings show support for internal consistency reliability and validity of the NIH-BFI, a clinician-administered measure of fatigue. Further testing in other clinical populations is recommended to obtain additional information on reliability and validity. The NIH-BFI provides a method for clinician-rated fatigue that may be a separate from depression.

Misunderstanding psychopathology as medical semiology: an epistemological enquiry

In our everyday clinical experience we encounter significant problems directly related to the instability of psychopathological concepts. In order to trace the origin of this inconsistency, the nature of these concepts will be explored in their historical development. They will be compared to those pertaining to medical semiology, paying special attention to the specific nature of the 'object' each of them refers to. While concepts belonging to medical semiology refer to natural objects and retain their meaning independently of the patient's context, psychopathological concepts refer to fragments of experience, which lose their significance if detached from their contextual horizon. The instability of psychopathological concepts is a consequence of the misunderstanding of psychopathology as medical semiology. As an alternative to this view, it will be argued that psychopathology represents an active and never-ending process aimed at the creation of intelligibility.

Phenotyping psychosis: room for neurocomputational and content-dependent cognitive endophenotypes?

INTRODUCTION

The endophenotype research strategy aims at reducing complex clinical phenomena to reveal a more tractable mapping to underlying genes. Cognitive dysfunctions have been widely pursued as target endophenotype in schizophrenia. We critically discuss the promise and limitations of this approach.

METHODS

Relevant theoretical and empirical issues on genes and behaviour, neurocognitive structure and psychopathology were selectively reviewed and discussed.

RESULTS

Some important inherent limitations of the current cognitive endophenotype approach were identified. These include reliance on (1) classic neuropsychology; (2) deficit measures; and (3) a general information processing approach with the use of content-independent, neutral stimuli. As a result, many current cognitive endophenotypes are likely to overlap and converge with general cognitive impairments, which may be shared with other disorders.

CONCLUSIONS

We propose three novel directions for further psychosis endophenotype research: (1) in addition to such content-independent computational processes, which operate in a similar way regardless of the stimuli, it is important to consider the potential roles of "content-dependent endophenotypes", which operate on different stimuli in consistently different manners. Advances in cognitive studies suggest there may be evolutionarily important aspects of cognition which are content-dependent. We propose that both content-independent and content-dependent processes should be addressed in psychosis research. (2) In line with the emphasis on content, close attention should be paid to the study of "psychopathological endophenotypes" in addition to cognitive endophenotypes. (3) "Neurocomputational endophenotypes" may be defined by parsing cognitive processes into "subsystems" with specific computational processing algorithms and considering key computational parameters suggested from these models. These potential "neurocomputational endophenotypes" (such as neuronal noise, synaptic learning algorithms) are potentially intermediate variables located between the levels of cognition and neurobiology.

Problems with retrospective studies of the presence of schizophrenia

Studies concerning the presence of schizophrenia in the distant past are controversial. Some authors maintain that schizophrenia-like illnesses existed in antiquity, while others argue that this is quite doubtful. Imprecise definition of schizophrenia, imposition of the current concept of schizophrenia onto the past, difficulties in interpreting ancient texts describing schizophrenia-like conditions, and cultural variables involved in the clinical definition of schizophrenia underlie these controversies. This article reviews the methodological issues that arise in such retrospective studies of schizophrenia.

How do experts recognize schizophrenia: the role of the disorganization symptom

OBJETIVE: Research on clinical reasoning has been useful in developing expert systems. These tools are based on Artificial Intelligence techniques which assist the physician in the diagnosis of complex diseases. The development of these systems is based on a cognitive model extracted through the identification of the clinical reasoning patterns applied by experts within the clinical decision-making context. This study describes the method of knowledge acquisition for the identification of the triggering symptoms used in the reasoning of three experts for the diagnosis of schizophrenia. METHOD: Three experts on schizophrenia, from two University centers in Sao Paulo, were interviewed and asked to identify and to represent the triggering symptoms for the diagnosis of schizophrenia according to the graph methodology. RESULTS: Graph methodology showed a remarkable disagreement on how the three experts established their diagnosis of schizophrenia. They differed in their choice of triggering-symptoms for the diagnosis of schizophrenia: disorganization, blunted affect and thought disturbances. CONCLUSIONS: The results indicate substantial differences between the experts as to their diagnostic reasoning patterns, probably under the influence of different theoretical tendencies. The disorganization symptom was considered to be the more appropriate to represent the heterogeneity of schizophrenia and also, to further develop an expert system for the diagnosis of schizophrenia.

Decision support system for the diagnosis of schizophrenia disorders

Clinical decision support systems are useful tools for assisting physicians to diagnose complex illnesses. Schizophrenia is a complex, heterogeneous and incapacitating mental disorder that should be detected as early as possible to avoid a most serious outcome. These artificial intelligence systems might be useful in the early detection of schizophrenia disorder. The objective of the present study was to describe the development of such a clinical decision support system for the diagnosis of schizophrenia spectrum disorders (SADDESQ). The development of this system is described in four stages: knowledge acquisition, knowledge organization, the development of a computer-assisted model, and the evaluation of the system's performance. The knowledge was extracted from an expert through open interviews. These interviews aimed to explore the expert's diagnostic decision-making process for the diagnosis of schizophrenia. A graph methodology was employed to identify the elements involved in the reasoning process. Knowledge was first organized and modeled by means of algorithms and then transferred to a computational model created by the covering approach. The performance assessment involved the comparison of the diagnoses of 38 clinical vignettes between an expert and the SADDESQ. The results showed a relatively low rate of misclassification (18-34%) and a good performance by SADDESQ in the diagnosis of schizophrenia, with an accuracy of 66-82%. The accuracy was higher when schizophreniform disorder was considered as the presence of schizophrenia disorder. Although these results are preliminary, the SADDESQ has exhibited a satisfactory performance, which needs to be further evaluated within a clinical setting.

Animal models of depression: navigating through the clinical fog

Animal models of human disease have proven of considerable value in elucidating basic pathophysiological mechanisms and in developing novel treatments. However, modelling human mental disorders in experimental animals is fraught with difficulties. Depression models generally lack both clinical and scientific credibility and have, thus far, failed to inform treatment strategies previously acquired through serendipity. The complexity and heterogeneity of the clinical states labelled 'depression' dictate that we continue to work with a crude and uninformative taxonomy within which 'core' clinical and pathophysiological features of depression are not clearly identified. Consequently, much of the neuroscience of animal modelling is framed around physiological and neurobiological phenomena that may be of relevance to only a minority of patients. Additionally, inferring pathophysiology from apparent treatment responses overestimates the efficacy of existing treatments and tends to ignore reliable demonstrations of the 'antidepressant effects' of non-pharmacological interventions. Whilst animal modelling remains a potentially important approach towards understanding neurobiological mechanisms in depression, we need to address the poverty of reliable clinical science that should inform model development.

[Descriptive psychopathology: is there a common language?]

We elaborated a review of some of the main books of descriptive psychopathology, Brazilian and international ones, with the objective of examining if there is uniformity among the various authors about concepts and terminology. We observed that there is not truly a common language: some concepts are used by some authors but are ignored by others; a same term is utilized with different meanings; and a same concept is assigned by different terms. Here some points of divergence among the various authors are presented and discussed.

Extrapyramidal symptoms and signs in first-episode, antipsychotic exposed and non-exposed patients with schizophrenia or related psychotic illness

Movement disorders in first-episode psychosis are increasingly recognized; however, the prevalence and clinical correlates are uncertain. We compared antipsychotic exposed (< 12 weeks) with nonexposed first-episode patients, and report prevalence as well as clinical and demographic variables associated with extrapyramidal dysfunction. Data are baseline assessments from a multicentre, international drug trial of first-episode psychosis (n = 535). Analysis included the Extrapyramidal Symptom Rating Scale, Premorbid Adjustment Scale, and the Positive and Negative Syndrome Scale. Of non-exposed patients, 28.1% (n = 47/167) had at least one mild sign of extrapyramidal dysfunction, as did 46.3% (n = 169/365) of previously exposed patients. Hypokinetic Parkinsonism was the most prevalent disorder. The severity of movement disorders and negative symptoms were correlated; however, the effect sizes were small. Logistic regression analysis indicated that the salient risk factors for all patients were: previous antipsychotic exposure [odds ratio (OR) = 2.4; 95% confidence interval (CI) 1.6-3.6] and poor premorbid functioning (OR = 1.8; 95% CI 1.2-2.6). For the non-exposed group (n = 167), the significant risk factors were: having severe mental illness in the family (OR = 2.9; 95% CI 1.2-7.2) and poor premorbid functioning (OR = 2.3; 95% CI 1.0-5.3). For the previously exposed group (n = 368), the significant variables were: poor premorbid functioning (OR = 1.8; 95%CI 1.2-2.8) and shorter duration of untreated psychosis (OR = 0.78; 95% CI 0.64-0.94). Although antipsychotic exposure was associated with extrapyramidal signs, the results indicate that many first-episode patients with no exposure to antipsychotics also had extrapyramidal dysfunction. In this group, family history and poor premorbid functioning appear to be associated with increased risk for movement disorders.

Information-Gathering Strategies in Behavioral Assessment

Summary: In behavioral assessment, the strategy theoretically most coherent for case formulation is to carry out a functional analysis aimed at discovering, among other factors, functionally relevant stimuli acting upon the problem-behavior. However, little is known about the decision-making processes involved in this task. Although many authors have suggested prescriptive models for this process, the strategies used by clinicians when gathering information seem to be left to experience and common sense. The present research is an attempt to increase the knowledge about this process of information gathering. The study was carried out with psychology students in their final year who already had enough theoretical knowledge to gather this kind of information, but still lacked practical experience. Subjects were asked to gather information aimed at checking a hypothesis about the functional role on a given behavior of either an antecedent or a subsequent (i.e., reinforcing) stimulus. The results show that information gathered to test a reinforcing stimulus hypothesis is more homogeneous than information to test a hypothesis about a functionally relevant antecedent stimulus. The strategies used to test both types of hypotheses are different. In both instances, however, subjects more frequently gathered information useful to refute or refine the hypothesis than information useful to verify it.

How many and which are the psychopathological dimensions in schizophrenia? Issues influencing their ascertainment

During the last two decades, much effort has been made to precisely characterize the symptom dimensions of schizophrenia. A number of dimensional models have been proposed, the most popular of which has been a three-dimensional model consisting of psychotic, negative and disorganizational symptoms. This model, however, has been criticized as too simplistic, and more complex models have been proposed, although to date there has been no consensus as to the number and nature of dimensions necessary to account for the whole range of schizophrenic symptoms. In the present paper, the authors review the main methodological issues which have led to the current confusion about the number of dimensions underlying schizophrenic psychopathology. Among the main issues influencing the delimitation of dimensions are: statistical procedures for determining the number of factors, phase of the illness, level of analysis of symptoms (i.e., symptoms or groups of symptoms), and measurement instrument used. Studies analyzing either a broad range of symptoms or particular symptoms at a finer level have produced a rather complex picture of schizophrenic dimensions. There is evidence supporting the existence of eight major dimensions of psychopathology: psychosis, disorganization, negative, mania, depression, excitement, catatonia and lack of insight. The dimensional structure of symptoms becomes even more complex if one considers that these big dimensions can be further divided into more elementary components. A hierarchical approach for organizing the complex dimensional structure of schizophrenic symptoms is proposed.

Toward a generalizable model of symptoms in major depressive disorder

BACKGROUND

This study has two goals: 1) to establish a generalizable model of the symptoms observed in outpatients with major depressive disorder (MDD); and 2) to compare symptom coverage of the Inventory of Depressive Symptomatology, Clinician-Rated (IDS-C) and Self-Report (IDS-SR) to that of the Hamilton Depression Rating Scale (HDRS) and Beck Depression Inventory (BDI).

METHODS

A factor analysis of IDS-C, IDS-SR, HDRS, and BDI items was carried out on 324 adult outpatients with MDD. Patients with coexisting Axis I or III illness or those taking psychotropic medication were excluded.

RESULTS

Ten primary factors were identified, six of which were substantially intercorrelated, defining a second-order factor of general depression severity. Schmid-Leiman orthogonalization identified the symptoms most associated with general severity.

CONCLUSIONS

The IDS provided more complete factors coverage than did the HDRS or BDI and thus may be more useful in research on symptom profiles.

Are positive and negative symptoms relevant to cross-sectional diagnosis of schizophrenic and schizoaffective patients?

The value of positive and negative symptoms for cross-sectional differential diagnosis was studied in a sample of 103 consecutively admitted patients with schizophrenia and schizoaffective psychoses. A semistructured interview for schizophrenia was used. Subjects were diagnosed by Research Diagnostic Criteria (RDC) and classified as schizophrenic, depressive schizoaffective, and manic schizoaffective disorders. DSM-III-R criteria for schizophrenia were used to assign RDC schizophrenics to two groups: "true" schizophrenic (fulfilling both DSM-III-R and RDC criteria) and schizophreniform (fulfilling RDC but not DSM-III-R criteria). The Scale for the Assessment of Positive Symptoms (SAPS) and Scale for the Assessment of Negative Symptoms (SANS) were used. Our findings showed that both positive and negative symptoms were relevant to differential diagnosis between schizophrenia and other psychotic disorders. However, negative symptoms presented higher significant differences between diagnostic groups than positive symptoms. These results were obtained by global ratings and by scoring on individual symptoms of SAPS and SANS. Treatment with neuroleptic and biperidene drugs did not alter symptomatologic differences between groups that resulted from repeated analyses of covariance. Certain symptoms and clusters of symptoms were found to be of higher severity of higher severity in only one diagnostic group. They were as follows: pressure of speech for manic schizoaffective disorder; guilt for depressive schizoaffective; high scores on negative symptoms for depressive schizoaffective and schizophrenic disorders; inappropriate affect for schizophrenic disorder; and three "psychomotor retardation" symptoms of the affective flattening subscale of SANS (unchanging facial expression, decreased spontaneous movements, and paucity of expressive gestures) for depressive schizoaffective disorder.(ABSTRACT TRUNCATED AT 250 WORDS)