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Biomedical subjects

M P Austin

Publications and source records attributed to M P Austin.

At least 37 records · Page 2Linked to original sources

Qualitative and quantitative analyses of a 'lock and key' hypothesis of depression.

BACKGROUND: We examine a 'lock and key' ('L-K') hypothesis to depression which posits that early adverse experiences establish locks that are activated by keys mirroring the earlier adverse experience to induce depression. METHODS: Two-hundred and seventy clinically depressed patients were examined with open-ended and pre-coded interview questions to ascertain both early adverse experiences and precipitating life events. Qualitative and quantitative data analyses examined for any associations between developmental 'locks' and precipitating 'keys'. RESULTS: Qualitative assessment suggested 'L-K' links in almost one-third of the sample, and examples are provided. While quantitative analyses indicated significant associations between several identical 'lock' and 'key' constructs, evidence of specificity was rare. When individual 'locks' and 'keys' were consolidated into three higher-order constructs, variable models were suggested, including a non-specific link, a specific link and absence of any link. 'L-K' links appeared more likely in those with 'non-melancholic' (versus 'melancholic') depression, with the seemingly greater relevance to 'reactive' (versus 'neurotic') depression in the quantitative analyses inviting speculation that that 'disorder' may be more a reaction to a salient rather than a severe stressor. CONCLUSIONS: This exploratory study suggests that early adverse experiences may variably establish specific and non-specific patterns of vulnerability to having depression triggered by exposure to salient mirroring life event stressors.

Adjustment Disorders↗

On modelling personality disorders: are personality style and disordered functioning independent or interdependent constructs?

Current descriptors of personality disorder (PD) are an amalgam of two constructs, personality style and/or disorder. We seek to determine whether their intrinsic personality style descriptors are proxy measures of, or independent of, disordered personality functioning. In a sample of depressed patients, psychiatrists rated 16 differing PD personality style vignettes and assessed eight differing manifestations of disordered functioning. When "personality" vignettes and identified personality clusters were intercorrelated with "disorder" variables, interdependence was generally evident, suggesting that the personality descriptors underpinning current definition of the PDs actually act as proxy criteria for assessing disorder because they are, in and of themselves, descriptors of pathological functioning. The obsessional personality vignette provided an exception, seeming to be independent of disordered function. Such results assist consideration of how best to model, define and measure the personality disorders.

Adolescent↗

"Acting out" and "acting in" as behavioral responses to stress: a qualitative and quantitative study.

In a sample of 270 depressed patients, we describe some behaviors in response to stress. One third acknowledged "acting out" behaviors--angry, destructive acts and "out of control" behaviors. Four fifths acknowledged "acting in" behaviors--most commonly withdrawal. As a percentage of subjects acknowledged both response styles (with alternate expression influenced by situation), we developed a dimensional self-report measure within a subsample of 177 who attended a follow-up reassessment. Assignment to four groups with contrasting expressions of "acting out" and "acting in" scores demonstrated differences in age, diagnostic status, age of onset of depression, and self-injurious behaviors.

Acting Out↗

An aetiological model of non-melancholic depression: study design and validity of the measures.

OBJECTIVE: The aim of this paper is to describe an approach to sub-typing non-melancholic depression and to determine which raters from a variety of backgrounds provided the most valid information on study variables. METHOD: A sample of non-melancholic depressed patients is described. Multiple raters (i.e. patients, psychiatrists, referrers and corroborative witnesses) completed measures of the patient's trait anxiety levels, severity of recent life event stressors and personality functioning. RESULTS: The study and representative data are reported. Congruence between several measures employed indicated that psychiatrist rating of disordered personality was superior to corroborative witness report. Assessment of anxiety traits indicated reasonable agreement between referrers and corroborative witnesses but poor agreement between those ratings and interview-elicited ratings. There were also discrepancies in quantifying 'severity' of life event stress, with patients and their corroborative witnesses rating such events as more severe than either the interviewing psychiatrist or psychiatrists involved in consensus rating sessions. Importantly, the psychiatrists' capacity to quantify the relative contribution of disordered personality, anxiety and life-event stress to the particular depressive episode was supported. CONCLUSIONS: Results indicate some of the difficulties in operationalising determinants that may contribute to and sub-type the non-melancholic depressions, and demonstrate the advantages of using a range of rating strategies and raters. In this study, psychiatrist-generated judgements are clearly favoured, although the advantages of also assessing trait anxiety and life-event stress impact by self-report strategies are conceded. Some techniques for estimating the contribution of disordered personality function, anxiety and life-event stress are offered for both their research and their clinical utility.

Adjustment Disorders↗

Use of psychotropic medications in breast-feeding women: acute and prophylactic treatment.

OBJECTIVES: The postnatal period is a time of increased onset and relapse of mental illness. It poses a clinical dilemma, as many mothers requiring medication acutely or prophylactically will also choose to breast feed. The present paper first reviews the safety of psychotropes in breast-fed infants and the usefulness of prophylaxis for women at risk of postpartum affective relapse and, second, provides guidelines in the use of psychotropic drugs in breast-feeding women. METHODS: A Medline review was conducted reviewing all papers published during the period 1993-1998 (and their associated bibliographies) on the use of psychotropes in breast-feeding women and the prophylactic usefulness of medications in women at risk of affective postpartum relapse. RESULTS: Findings are based on case reports and small, mostly uncontrolled studies. Both tricyclic antidepressants (TCA) and specific serotonin re-uptake inhibitors (SSRIs) appear to be relatively safe in breast feeding. Antidepressants commenced in the early postpartum period may reduce depressive relapse. While prophylactic lithium appears to significantly reduce relapse of affective psychosis in the puerperium, there have been no studies of the anticonvulsants in the puerperium. Finally, high dose antipsychotics should be avoided, as they may be associated with long-term adverse sequelae in the infant. CONCLUSIONS: On the basis of current knowledge, the use of SSRIs, TCA, carbamazepine, sodium valproate and short-acting benzodiazepines in breast feeding is relatively safe. If lithium is to be used, close collaboration with a paediatrician is essential. The long-term risks of antipsychotics, especially at high doses, remain to be clarified. Before a decision can be made, the risk-benefit ratio must be clearly outlined and discussed with the mother and her partner.

Antidepressive Agents, Tricyclic↗

Neural network subtyping of depression.

OBJECTIVE: To examine the applicability of a neural network classification strategy to examine the independent contribution of psychomotor disturbance (PMD) and endogeneity symptoms to the DSM-III-R definition of melancholia. METHOD: We studied 407 depressed patients with the clinical dataset comprising 17 endogeneity symptoms and the 18-item CORE measure of behaviourally rated PMD. A multilayer perception neural network was used to fit non-linear models of varying complexity. A linear discriminant function analysis was also used to generate a model for comparison with the non-linear models. RESULTS: Models (linear and non-linear) using PMD items only and endogeneity symptoms only had similar rates of successful classification, while non-linear models combining both PMD and symptoms scores achieved the best classifications. CONCLUSIONS: Our current non-linear model was superior to a linear analysis, a finding which may have wider application to psychiatric classification. Our non-linear analysis of depressive subtypes supports the binary view that melancholic and non-melancholic depression are separate clinical disorders rather than different forms of the same entity. This study illustrates how non-linear modelling with neural networks is a potentially fruitful approach to the study of the diagnostic taxonomy of psychiatric disorders and to clinical decision-making.

Behavioral Symptoms↗

Dysfunctional parenting: over-representation in non-melancholic depression and capacity of such specificity to refine sub-typing depression measures.

We examine the proposition that dysfunctional parenting is more likely to be experienced by those with non-melancholic (compared to melancholic) depression and that, as a consequence, such specificity allows the validity of varying definitions of melancholia to be examined and their utility sharpened. We study a sample of 245 non-psychotic patients meeting DSM-III-R criteria for a major depressive episode and assign them to melancholic and non-melancholic sub-sets according to five separate sub-typing measures (DSM-III-R; DSM-IV; Newcastle; 'Clinical' and CORE criteria). We assess dysfunctional parenting by use of the Parental Bonding Instrument (PBI), and by structured psychiatrist assessment and self-report ratings of a range of dysfunctional parental experiences, with independent assessment and self-report ratings of a range of dysfunctional parental experiences, with independent assessment of the last by reports from corroborative witnesses and from the patients' referring therapists. The five sub-typing measures assigned varying percentages of the sample (24-42%) to a 'melancholic' sub-type. When Newcastle Index assignments were examined, there was no evidence that dysfunctional parenting had any specificity to non-melancholic depression. Neither the DSM-III-R nor DSM-IV systems demonstrated specificity in relation to PBI scores, but several interview-assessed dysfunctional parenting characteristics were over-represented in their non-melancholic sub-sets. 'Clinical' definition showed the greatest over-representation of dysfunctional parenting to those assigned as having non-melancholic depression. The CORE measure, a behaviourally weighted measure of psychomotor disturbance, was the next most differentiating. Importantly, those assigned as having non-melancholic depression by all five measures were more likely to be rated by corroborative witnesses as being exposed to anomalous parenting, validating the subjects' self-reports, arguing against results being an artefact of clinician-based assessment, and supporting the specificity of dysfunctional parenting to a depressive sub-type.

Adolescent↗

Plumbing the depths: some problems in quantifying depression severity.

We first report further studies of the psychometric properties of the AUSSI), a brief (11-item) self-report depression measure assessing mood state severity and disability in a sample of 270 subjects. Total scores (combining mood state and disability) correlated well with another self-report measure of depression severity, the Beck, but minimally with both Hamilton and DSM-III-R Global Assessment of Function (GAF) scores. For a sub-sample where we had complete data sets (including a corroborative witness [CW] form of the AUSSI), we established moderate levels of agreement between self-report and CW AUSSI scores, important in supporting validity of its disability sub-scale. Against expectation, neither mood nor disability AUSSI scale scores differed across clinically meaningful depressive sub-types, while differentiation was demonstrated for the Hamilton and GAF measures. Differentiation for the Hamilton measure was clearly driven by several type-specific component clinical features, but also presumably contributed to by the clinician-rater format. Our study raises questions about the varying reference bases and semantics used by patients, corroborative witnesses and clinicians in rating depression severity, and which may generate similar or contrasting severity estimates across varying depressive sub-types.

Adolescent↗

Distinguishing psychotic depression from melancholia.

We contrast 25 patients with "psychotic depression" (PD) against two age- and sex-matched groups of melancholic depressed patients. In terms of clinical features, specificity of PD was suggested for several features, including delusions, morbid cognitions (involving guilt and a sense of deserving punishment), hallucinations and constipation. In addition, the PDs had significantly higher levels of behaviourally rated psychomotor disturbance. A comprehensive list of risk factors to depression (e.g., socio-demographic, family history, parental influences, medical disorders, anxiety, stressors and personality style) were examined, without clear differentiation between the comparison groups apart from the suggestion that being a "worrier" and having tenuous stability under stress was over-represented in the PDs. Findings favour the view that psychotic depression is a sub-type of melancholic depression (accounting for the similar expression of the majority of clinical and possible aetiological variables across our contrasted "types'). Findings also suggest possible benefits from future phenomenological studies of psychotic depression relying more on observer-based rather than self-report or symptom data sets. Aetiological studies would benefit from focussing on those features identified as distinguishing the condition from melancholic depression.

Adult↗

Increased rate of psychosis and psychomotor change in depression with age.

BACKGROUND: We examined the phenomenology of depression in younger (< 60 years old) versus older (> or = 60 years) subjects and, more specifically, the interaction between age and psychomotor disturbance associated with depression. METHOD: Two hundred and eighty-five patients with a DSM-III-R diagnosis of unipolar major depression referred to a mood disorders unit were assessed using the CORE rating scale, a sign-based system for defining melancholia. Subjects were also assessed using the Hamilton Rating Scale for Depression, Zung Depression Scale, Newcastle Endogenous Depression Inventory and the General Health Questionnaire. RESULTS: The total CORE score (and each of its subscales) was found to interact with age. Rates of psychotic and melancholic depression increased with age. Elderly depressives suffered more severe depression (higher HRSD scores), appetite loss and weight loss. Level of psychomotor disturbance and rates of psychosis did not differ between those elderly subjects with an early onset (before the age of 60 years) and those with a late onset (at or after 60 years) of depression. CONCLUSIONS: There appear to be robust phenomenological differences in depression between older and younger subjects. The association between age and psychomotor change may assist our understanding of the neurobiology of depression.

Adult↗

The development of a refined measure of dysfunctional parenting and assessment of its relevance in patients with affective disorders.

BACKGROUND: The Parental Bonding Instrument (PBI) measures fundamental parenting dimensions (care and over-protection), but does not directly assess abusive parenting. METHODS: We describe the development of the Measure of Parenting Style (the MOPS), comprising refined PBI scales assessing parental indifference and over-control, as well as a scale assessing parental abuse. RESULTS: We examine psychometric properties of the MOPS, while several analyses build to the concurrent validity of the abuse scale as an experimental measure. We examine the extent to which both the PBI and the MOPS scales showed specificity of dysfunctional parenting to the non-melancholic depressive subtype, and across a range of anxiety disorders. Non-melancholic depressed patients returned anomalous parenting scale scores (compared to melancholic subjects), but only when such subtyping decisions were clinician-generated. Those receiving DSM-III-R lifetime anxiety diagnoses of panic disorder and of social phobia returned higher PBI protection and MOPS over-control scores than non-anxious subjects, while differences were not established for those with generalized anxiety disorder or obsessive compulsive disorder. CONCLUSIONS: We consider the likely utility of the MOPS scale and note the module capacity of separate MOPS and PBI scales, which allow a set of options for assessing perceived parenting characteristics.

Adolescent↗

Defining the personality disorders: description of an Australian database.

OBJECTIVE: We seek to improve the definition and classification of the personality disorders (PDs) and derive a large database for addressing this objective. METHOD: The paper describes the rationale for the development of a large set of descriptors of the PDs (including all DSM-IV and ICD-10 descriptors, but enriched by an additional 109 items), the design of parallel self-report (SR) and corroborative witness (CW) measures, sample recruitment (of 863 patients with a priori evidence of personality disorder or disturbance) and preliminary descriptive data. RESULTS: Analyses (particularly those comparing ratings on molar PD descriptions with putative PD dimensions) argue for acceptable reliability of the data set, while both the size of the sample and the representation of all PD dimensions of interest argue for the adequacy of the database. CONCLUSIONS: We consider in some detail current limitations to the definition and classification of the PDs, and foreshadow the analytic techniques that will be used to address the key objectives of allowing the PDs to be modelled more clearly and, ideally, measured with greater precision and validity.

Adult↗

Subcortical hyperintensities on magnetic resonance imaging: clinical correlates and prognostic significance in patients with severe depression.

In 39 hospital inpatients with severe primary depressive disorders, we evaluated the relationships between subcortical hyperintensities on magnetic resonance imaging (MRI) and clinical features, neuropsychological impairment and response to standard therapies. Both white matter and gray nuclei lesions were associated with older age and the absence of a family history of affective disorder. White matter hyperintensities were also associated with onset of first affective episode after the age of 50 years and impaired psychomotor speed. Most importantly, the severity of white matter hyperintensities predicted a poorer response to treatment (r = -0.44, p < .01). Negative correlations of the same order were detected in those (n = 20) who received electroconvulsive therapy (r = -0.42, p = .06) and those (n = 19) who received pharmacotherapy alone (r = -.49, p < .05). This study provides preliminary evidence supporting the clinical and prognostic significance of extensive white matter hyperintensities in patients with severe depression.

Activities of Daily Living↗

Sub-typing depression, I. Is psychomotor disturbance necessary and sufficient to the definition of melancholia?

Melancholia is most commonly distinguished from non-melancholic depression by the presence of psychomotor disturbance (PMD) and a set of 'endogeneity' symptoms. We examine the capacity of an operationalized clinician-rated measure of PMD (the CORE system) to predict diagnostic assignment to 'melancholic/endogenous' classes by the DSM-III-R and Newcastle systems. Examining a pre-established CORE cut-off score (> or = 8) against independent diagnostic assignment, PMD was present in 51% of those assigned as melancholic by DSM-III-R, and 85% of those assigned as endogenous by the Newcastle system, quantifying the extent to which it is 'necessary' to the two definitions of 'melancholia'. Additionally, multivariate analyses established that the addition of a refined set of historically suggested endogeneity symptoms added only slightly to overall discrimination of melancholic and non-melancholic depressives. While only few endogeneity symptoms independent of psychomotor disturbance were suggested, their specific relevance varied against system definition of melancholia (appetite/weight loss and terminal insomnia being identified for DSM-III-R; anhedonia for Newcastle; and diurnal variation in mood and energy for both systems). Results allow consideration of the relative importance of two domains (psychomotor disturbance and 'endogeneity' symptoms) to clinical definition of melancholia, and have the potential to assist both classification and pursuit of neurobiological determinants. We interpret findings as suggesting a 'core and mantle' model for conceptualizing the clinical features of melancholia, with psychomotor disturbance as the core and with independent endogeneity symptoms as only a thin mantle.

Adult↗

Sub-typing depression, II. Clinical distinction of psychotic depression and non-psychotic melancholia.

We have attempted to clarify clinical differentiating features of psychotic depression. Forty-six depressed subjects meeting DSM-III-R criteria for major depression with psychotic features were compared with (i) DSM-defined melancholic, (ii) Newcastle-defined endogenous, and (iii) a residual DSM-defined major depressive episode group. Additionally, a 'bottom up' latent class analysis (LCA) suggested a larger sample of 82 'psychotic depressive' subjects, and multivariate analyses contrasted these subjects with both LCA-identified melancholic and all residual depressed subjects. Analyses suggested that, in addition to two features with absolute specificity (delusions and hallucinations), both the DSM-defined and LCA-defined 'psychotic depressive' subjects were significantly more likely to demonstrate marked psychomotor disturbance, to report two morbid cognitions (feeling sinful and guilty; feeling deserving of punishment), as well as be more likely to report constipation, terminal insomnia, appetite/weight loss and (variable across the defined 'psychotic depressive' groups) loss of interest and pleasure. The study identifies a wider set of potentially discriminating clinical variables than previous studies, as well as both indicating the existence and assisting identification of 'true' psychotic depression in the absence of formal psychotic features being acknowledged or elicited.

Adult↗

A clinical perspective on SPECT.

The potential clinical utility of SPECT (Single Photon Emission Computed Tomography) brain imaging to clarifying certain diagnostic dilemmas faced by clinical psychiatrists is considered generally and is illustrated by several case vignettes. Three case histories consider dementia vs depressive pseudodementia, two the possibility of a cerebral vasculitis in patients with auto-immune conditions, and two whether the patient had a "type" of depression likely to benefit from a course of ECT. Published studies reviewing the utility of SPECT in dementia, depression, depressive "pseudodementia" and cerebral lupus are considered. It is suggested that SPECT is an important investigatory technique providing additional information that may assist some diagnostic decisions, while its utility in assisting other clinical decisions awaits clarification.

Adult↗

Uptake of 99mTc-exametazime shown by single photon emission computerized tomography in obsessive-compulsive disorder compared with major depression and normal controls.

Twelve patients with obsessive-compulsive disorder (OCD) were investigated at rest using single photon emission computerized tomography with 99mTc-exametazime. The uptake of 99mTc-exametazime was expressed relative to calcarine/occipital cortex. Patients were matched for drug treatment with 12 patients with a major depressive episode and the patient groups were compared with a control group. Significant bilateral decreases in tracer uptake were confined to basal ganglia in the OCD group. There was a paradoxical positive correlation between anxiety ratings and tracer uptake to basal ganglia in the OCD group. The findings confirm that the functional topography of OCD implicates altered function in the basal ganglia.

Adult↗