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T Slade

Publications and source records attributed to T Slade.

12 recordsLinked to original sources
PubMed2006

Clinical, enzymatic and molecular characterization of nine new patients with malonyl-coenzyme A decarboxylase deficiency.

We report nine new patients with malonic aciduria associated with enzyme-confirmed malonyl-CoA decarboxylase (MCD) deficiency in eight. Clinical details were available on eight, and molecular genetic characterization was obtained for nine. As for 15 previously described patients, cardinal clinical manifestations included developmental delay and cardiomyopathy; metabolic perturbations (e.g. acidosis) and seizures, however, were infrequent or not observed in our patients. For all, detection of elevated malonic acid in urine (+/- increased C3DC acylcarnitine by analysis employing tandem mass spectrometry) led to pursuit of enzyme studies. MCD activities (nmol/h PER mg protein) revealed: control (n = 22), 16.2 +/- 1.8 (SEM; range 5.7-46.2); patients (n = 8, assayed in duplicate), 1.7 +/- 0.3 (10% of parallel control; range 0.6-2.8). Molecular characterization by DNA sequence analysis and multiplex ligation-dependent probe amplification revealed nine novel mutations (c.796C>T; p.Gln266X, c.481delC; p.Leu161CysfsX18, c.1367A>C; p.Tyr456Ser, c.1319G>T; p.Ser440Ile, c.1430C>T; p.Ser477Phe, c.899G>T; p.Gly300Val, c.799-1683_949-1293del3128, and two other large genomic deletions comprising exons 1 or the complete gene) and two known mutations in the MLYCD gene. Our findings increase the number of enzyme-confirmed MCD-deficient patients by >50%, and expand our understanding of the phenotypic and molecular heterogeneity of this rare disorder.

Adolescent↗
PubMed2004

Twelve-month prevalence and disability of DSM-IV bipolar disorder in an Australian general population survey.

BACKGROUND: There have been few large-scale epidemiological studies which have examined the prevalence of bipolar disorder. The authors report 12-month prevalence data for DSM-IV bipolar disorder from the Australian National Survey of Mental Health and Well-Being. METHOD: The broad methodology of the Australian National Survey has been described previously. Ten thousand, six hundred and forty-one people participated. The 12-month prevalence of euphoric bipolar disorder (I and II)--similar to the euphoric-grandiose syndrome of Kessler and co-workers--was determined. Those so identified were compared with subjects with major depressive disorder and the rest of the sample, on rates of co-morbidity with anxiety and substance use disorders as well as demographic features and measures of disability and service utilization. Polychotomous logistic regression was used to study the relationship between the three samples and these dependent variables. RESULTS: There was a 12-month prevalence of 0-5 % for bipolar disorder. Compared with subjects with major depressive disorder, those with bipolar disorder were distinguished by a more equal gender ratio; a greater likelihood of being widowed, separated or divorced; higher rates of drug abuse or dependence; greater disability as measured by days out of role; increased rates of treatment with medicines; and higher lifetime rates of suicide attempts. CONCLUSIONS: This large national survey highlights the marked functional impairment caused by bipolar disorder, even when compared with major depressive disorder.

Adolescent↗
PubMed2003

The performance of the K6 and K10 screening scales for psychological distress in the Australian National Survey of Mental Health and Well-Being.

BACKGROUND: Two new screening scales for psychological distress, the K6 and K10, have been developed but their relative efficiency has not been evaluated in comparison with existing scales. METHOD: The Australian National Survey of Mental Health and Well-Being, a nationally representative household survey, administered the WHO Composite International Diagnostic Interview (CIDI) to assess 30-day DSM-IV disorders. The K6 and K10 were also administered along with the General Health Questionnaire (GHQ-12), the current de facto standard of mental health screening. Performance of the three screening scales in detecting CIDI/DSM-IV mood and anxiety disorders was assessed by calculating the areas under receiver operating characteristic curves (AUCs). Stratum-Specific Likelihood Ratios (SSLRs) were computed to help produce individual-level predicted probabilities of being a case from screening scale scores in other samples. RESULTS: The K10 was marginally better than the K6 in screening for CIDI/DSM-IV mood and anxiety disorders (K10 AUC: 0.90, 95%CI: 0.89-0.91 versus K6 AUC: 0.89, 95%CI: 0.88-0.90), while both were significantly better than the GHQ-12 (AUC: 0.80, 95%CI: 0.78-0.82). The SSLRs of the K10 and K6 were more informative in ruling in or out the target disorders than those of the GHQ-12 at both ends of the population spectrum. The K6 was more robust than the K10 to subsample variation. CONCLUSIONS: While the K10 might outperform the K6 in screening for severe disorders, the K6 is preferred in screening for any DSM-IV mood or anxiety disorder because of its brevity and consistency across subsamples. Precision of individual-level prediction is greatly improved by using polychotomous rather than dichotomous classification.

Adolescent↗
PubMed2003

Social phobia in the Australian National Survey of Mental Health and Well-Being (NSMHWB).

BACKGROUND: This article reports data on social phobia from the first large scale Australian epidemiological study. Prevalence rates, demographic correlates and co-morbidity in the sample that met criteria for social phobia are reported and gender differences examined. METHOD: Data were obtained from a stratified sample of 10641 participants as part of the Australian National Survey of Mental Health and Well-Being (NSMHWB). A modified version of the Composite International Diagnostic Interview (CIDI) was used to determine the presence of social phobia, as well as other DSM-IV anxiety, affective and substance use disorders. The interview also screened for the presence of nine ICD-10 personality disorders, including anxious personality disorder, the equivalent of DSM-IV avoidant personality disorder (APD). RESULTS: The estimated 12 month prevalence of social phobia was 2.3%, lower than rates reported in several recent nationally representative epidemiological surveys and closer to those reported in the Epidemiological Catchment Area study (ECA) and other DSM-III studies. Considerable co-morbidity was identified. Data indicated that the co-morbidity with depression and alcohol abuse and dependence were generally subsequent to onset of social phobia and that the additional diagnosis of APD was associated with a greater burden of affective disorder. Social phobia most often preceded major depression, alcohol abuse and generalized anxiety disorder. CONCLUSIONS: Social phobia is a highly prevalent, highly co-morbid disorder in the Australian community. Individuals with social phobia who also screen positively for APD appear to be at greater risk of co-morbidity with all surveyed disorders except alcohol abuse or dependence.

Adolescent↗
PubMed2001

DSM-IV and ICD-10 generalized anxiety disorder: discrepant diagnoses and associated disability.

BACKGROUND: It is commonly assumed that diagnoses according to DSM-IV and ICD-10 are equivalent. Recent discussions on generalized anxiety disorder (GAD) have suggested that ICD-10 criteria may be identifying a milder form of the disorder than DSM-IV. This report examines prevalence and associated disability of DSM-IV and ICD-10 GAD. METHODS: The Composite International Diagnostic Interview was administered to a community sample of 10,641 people, and the diagnostic criteria that contributed to discrepancies between DSM-IV and ICD-10 GAD were identified. A multiple linear regression analysis was carried out to determine the strength of the relationship between disability, as measured by the SF-12, and discrepant diagnoses of GAD. RESULTS: The concordance between DSM-IV and ICD-10 GAD was fair (kappa = 0.39). The two sources of discrepancy when DSM-IV was positive and ICD-10 was negative resulted from the requirement in ICD-10 that the respondent endorse symptoms of autonomic arousal (ICD-10 criterion B) and the requirement that ICD-10 GAD does not co-occur with panic/agoraphobia, social phobia or obsessive-compulsive disorder (ICD-10 criterion C). The two major sources of discrepancy when ICD-10 was positive and DSM-IV was negative resulted from the requirement in DSM-IV that the worry be excessive (DSM-IV criterion A) and that it causes clinically significant distress or impairment (DSM-IV criterion E). DSM-only GAD cases had significantly higher levels of disability than ICD-only cases of GAD after controlling for demographic variables and the presence of comorbid psychiatric disorders. CONCLUSIONS: While the prevalence rates for DSM-IV and ICD-10 GAD are almost identical, these classification systems are diagnosing different groups of people.

Adult↗
PubMed2001

Interpreting scores on the Kessler Psychological Distress Scale (K10).

OBJECTIVE: To provide normative data on the Kessler Psychological Distress Scale (K10), a scale that is being increasingly used for clinical and epidemiological purposes. METHOD: The National Survey of Mental Health And Well-Being was used to provide normative comparative data on symptoms, disability, service utilisation and diagnosis for the range of possible K10 scores. RESULTS: The K10 is related in predictable ways to these other measures. IMPLICATIONS: The K10 is suitable to assess morbidity in the population, and may be appropriate for use in clinical practice.

Adolescent↗
PubMed2000

Working memory dysfunction in major depression: an event-related potential study.

OBJECTIVES: To study working memory function in untreated major depression using a digit probe identification and matching task. METHODS: We compared behavioural performance and event-related potentials during processing of the Sternberg working memory task in 14 depressed patients and 14 healthy matched control subjects. RESULTS: Patients made more mistakes than controls as the memory load was increased from one to 5 digits and had significantly slower reaction times at all levels of memory load. The patients' event-related potentials (ERPs) differed significantly from controls. Pathological changes were similar for auditory and visual presentation. Surface negative activity in the 157-210 ms section of the waveform was reduced for all levels of memory load, suggesting abnormal sensory/perceptual processing in the modality-specific association cortices, possibly due to a failure of selective attention mechanisms. In the 375-840 ms epoch, the patients' responses showed large amplitude sustained negative activity, maximal at Cz and a reduced late positive wave. The large prolonged negativity in the patients' ERPs suggests activation of additional neuronal assemblies than those normally participating in the task. This could reflect either compensatory mechanism or dysfunction of inhibitory systems. These changes were sensitive to memory load, suggesting that they reflect alterations of memory-related processes. CONCLUSIONS: This study provides objective evidence that major depression significantly affects working memory. The ERP changes in depression could be accounted for by dysfunction of the central executive control of working memory.

Adult↗
PubMed2000

Why does the burden of disease persist? Relating the burden of anxiety and depression to effectiveness of treatment.

Why does the burden of mental disorders persist in established market economies? There are four possibilities: the burden estimates are wrong; there are no effective treatments; people do not receive treatment; or people do not receive effective treatments. Data from the Australian National Survey of Mental Health and Wellbeing about the two commonest mental disorders, generalized anxiety disorder and depression, have been used in examining these issues. The burden of mental disorders in Australia is third in importance after heart disease and cancer, and anxiety and depressive disorders account for more than half of that burden. The efficacy of treatments for both disorders has been established. However, of those surveyed, 40% with current disorders did not seek treatment in the previous year and only 45% were offered a treatment that could have been beneficial. Treatment was not predictive of disorders that remitted during the year. The burden therefore persists for two reasons: too many people do not seek treatment and, when they do, efficacious treatments are not always used effectively.

Adult↗
PubMed1999

A comparison of ICD10 and DSM-IV criteria for posttraumatic stress disorder.

The assumption that participants receiving an ICD10 diagnosis of posttraumatic stress disorder (PTSD) will also receive a DSM-IV diagnosis of PTSD was tested. Data were gathered for 1,364 participants using the Composite International Diagnostic Interview (CIDI). The 12-month prevalence of PTSD was 3% for DSM-IV and 7% for ICD10 Diagnostic Criteria for Research (ICD10-DCR). The agreement between the two systems was fair (kappa = .50). Forty eight percent of the discrepancies between the systems were accounted for by the additional criterion requiring clinically significant distress or impairment included in DSM-IV. The inclusion of symptoms of general numbing of responsiveness accounted for 18% of the discrepancies. It is concluded that ICD10-DCR PTSD cannot be assumed to be identical to DSM-IV PTSD.

Adolescent↗
PubMedDate not supplied

Event-related potential (ERP) correlates of performance of intelligence tests.

Any relationship between measures of cognitive function and brain electrical activity would be of considerable importance in the objective assessment of patients suspected of intellectual impairment. In healthy subjects, we have found a strong correlation between the event-related potentials evoked by a digit probe identification task and scores on intelligence tests (WAIS). Responses from subjects with higher performance on IQ tests are significantly 'more negative' than those from subjects with lower IQ. The characteristics of these IQ-dependent electrophysiological features suggest that they may be related to the subject's ability to focus on a task.

Adult↗
PubMedDate not supplied

Wave form variations in auditory event-related potentials evoked by a memory-scanning task and their relationship with tests of intellectual function.

The inter-subject wave form variability of auditory event-related potentials (ERPs) evoked by digit probe identification in a memory-scanning task (Sternberg paradigm) and the effects of reaction time (RT) and task difficulty were studied in 26 healthy subjects. The response wave forms were compared with the performance of psychological tests of intelligence and memory. ERPs to 1-digit sets consisted of a sequence of waves identified as P100, N170, P250, N290, P400, P560 and N640. The major inter-subject difference in the response wave form was either the presence or absence of the late parietal positive wave P560. This wave occurred significantly more often in responses associated with larger memory sets and slow RT, suggesting that its presence reflects subjective difficulty in performing a task. With increasing set size, the P400 showed variable effects in different subjects, ranging from relative preservation of amplitude, through attenuation, to replacement or overlap by a broad surface-negative wave. This predominantly 'negative-going' effect of increasing task difficulty on the P400 was significantly correlated with scores of psychological tests; the greater the amplitude difference between the responses to easy and more difficult tasks, the better the scores, suggesting that these wave form changes reflect a more effective cognitive processing mechanism.

Acoustic Stimulation↗