Cavum septum pellucidum and adhesio interthalamica in schizophrenia: an MRI study

Several studies have independently suggested that patients with schizophrenia are more likely to have an enlarged cavum septum pellucidum (CSP) and an absent adhesio interthalamica (AI), respectively. However, neither finding has been consistently replicated and it is unclear whether there is an association between these two midline brain abnormalities. Thus, we compared the prevalence of absent AI and the prevalence, size and volume of CSP in 38 patients with schizophrenia and 38 healthy controls using magnetic resonance imaging (MRI). There were no between group differences in the presence or volume of CSP; however, an enlarged CSP was commoner among patients than controls. There was also a positive correlation between CSP ratings and volumes. No differences in the presence or absence of the AI were found between patients and controls; however, an absent AI was commoner in male patients with schizophrenia than females. There was absolutely no overlap between the presence of a large CSP and an absence of AI. In conclusion, our findings are in line with several case series and other MRI investigations that have shown a higher incidence of putatively developmental brain abnormalities in patients with schizophrenia, particularly in males, and support the neurodevelopmental model of this disorder.

Clinical validity and intrarater and test-retest reliability of the Structured Clinical Interview for DSM-5 - Clinician Version (SCID-5-CV)

AIM

The Structured Clinical Interview for the DSM is one of the most used diagnostic instruments in clinical research worldwide. The current Clinician Version of the instrument (SCID-5-CV) has not yet been assessed in respect to its psychometric qualities. We aimed to assess the clinical validity and different reliability indicators (interrater test-retest, joint interview, face-to-face vs telephone application) of the SCID-5-CV in a large sample of 180 non-prototypical and psychiatric patients based on interviews conducted by raters with different levels of clinical experience.

METHODS

The SCID-5-CV was administered face-to-face and by telephone by 12 psychiatrists/psychologists who took turns as raters and observers. Clinical diagnoses were established according to DSM-5 criteria and the longitudinal, expert, all data (LEAD) procedure. We calculated the percentage of agreement, diagnostic sensitivity and specificity, and the level of agreement (kappa) for diagnostic categories and specific diagnoses.

RESULTS

The percentage of positive agreement between the interview and clinical diagnoses ranged between 73% and 97% and the diagnostic sensitivity/specificity were >0.70. In the joint interview, the levels of positive agreement were high (>75%) and kappa levels were >0.70 for most diagnoses. The values were less expressive, but still adequate, for interrater test-retest interviews.

CONCLUSION

The SCID-5-CV presented excellent reliability and high specificity as assessed with different methods. The clinical validity of the instrument was also confirmed, which supports its use in daily clinical practice. We highlight the adequacy of the instrument to be used via telephone and the need for careful use by professionals with little experience in psychiatric clinical practice.

Performance of schizophrenic patients in the Stroop Color Word Test and electrodermal responsiveness after acute administration of cannabidiol (CBD)

OBJECTIVE

The last decade has seen increasing evidence of dysfunctions in the endogenous cannabinoid system in schizophrenia and of its relationship with the typical cognitive impairment of the disorder. Studies in animal models, healthy volunteers, and psychotic patients clearly suggest an antipsychotic-like effect of cannabidiol. This study investigated the effects of cannabidiol on selective attention in 28 schizophrenic patients using the Stroop Color Word Test and on these patients' electrodermal responsiveness to auditive stimuli.

METHOD

The subjects attended two experimental sessions, the first one without the administration of drugs. In the second session the subjects were divided into three groups that received either a single dose of cannabidiol 300 mg or cannabidiol 600 mg or placebo.

RESULTS

The three groups did not differ significantly with respect to electrodermal measures in the two experimental sessions. When the first and second sessions were compared improved performance was found in all three groups, with patients who received placebo and cannabidiol 300 mg performing better than those who received cannabidiol 600 mg.

CONCLUSION

The single, acute administration of cannabidiol seems to have no beneficial effects on the performance of schizophrenic patients in the Stroop Color Word Test, although the hypothesis that chronic administration may lead to improvement cannot be disregarded.

[Cannabis and mood]

OBJECTIVE

Evaluate the relationship between acute and chronic use of cannabis and mood changes.

METHOD

Articles were selected by electronic search in PubMed. Chapters in books and reference lists of selected articles were also reviewed. As the research did not involve humans, there was no evaluation by a Research Ethics Committee.

RESULTS

High rates of comorbidity between use/abuse/dependence of cannabis and affective disorders in longitudinal studies and in clinical samples were observed. Longitudinal studies indicate that, in long-term, the higher use of cannabis is associated with an increased risk of developing bipolar disorder, and probably, major depression in subjects initially without affective disorder, but was not found increased risk of cannabis use among those initially only with mania or depression. Another important observation is that substance abuse in bipolar patients may be associated with a number of negative characteristics, such as difficulty in recovering the affective symptoms, more hospitalizations, poor compliance with treatment, increased risk of suicide, aggression and a poor response to lithium. Psychosocial and pharmacological treatments are indicated for the management of comorbidity between cannabis and affective disorders.

CONCLUSION

The relationship between cannabis use and mood changes are observed both in the epidemiological research and in the clinical settings.

Bits and q-bits in a psychiatric ward

The present study is a trial on expressing the whole state of a psychiatric ward as a linear combination of base states in a Hilbert space. Real data were collected by observing the behavior of the patients from the psychiatric ward of the Clinical Hospital from Faculdade de Medicina de Ribeirão Preto for 12 days and, according to standard procedures, 18 behavioral parameters were daily measured for each patient. The whole data set was analyzed and, by taking the standard grades as eigenstates, the state of the ward was daily expressed by a linear combination of them, allowing the estimation of state transition matrices and of the quantum variability measure. Coefficients of the linear combination can be interpreted as square roots of probabilities and informational entropy is associated to each state resulting in the classical variability measure. Temporal evolutions of the classical and quantum variability measures are plotted trying to relate them to the behavioral state of the whole ward.

Cannabidiol monotherapy for treatment-resistant schizophrenia

Cannabidiol (CBD), one of the major products of the marijuana plant, is devoid of marijuana's typical psychological effects. In contrast, potential antipsychotic efficacy has been suggested based on preclinical and clinical data (Zuardi et al., 2002). In this report, we further investigated the efficacy and safety of CBD monotherapy in three patients with treatment-resistant schizophrenia (TRS). This was an in-patient study. All patients were given placebo for the initial 5 days, and from the 6th to 35th day (inclusive) they received CBD (initial oral dose of 40 mg reaching 1280 mg/day). On the 36th day, CBD treatment was discontinued and replaced by placebo for 5 days, which was subsequently switched to olanzapine for over 15 days. Efficacy, tolerability and side effects were assessed. One patient showed mild improvement, but two patients didn't show any improvement during CBD monotherapy. All patients tolerated CBD very well and no side effects were reported. These preliminary data suggest that CBD monotherapy may not be effective for TRS.

Proton magnetic resonance spectroscopy of the frontal lobe in schizophrenics: a critical review of the methodology

Schizophrenic patients undergoing proton magnetic resonance spectroscopy show alterations in N-acetyl aspartate levels in several brain regions, indicating neuronal dysfunction. The present review focuses on the main proton magnetic resonance spectroscopy studies in the frontal lobe of schizophrenics. A MEDLINE search, from 1991 to March 2004, was carried out using the key-words spectroscopy and schizophrenia and proton and frontal. In addition, articles cited in the reference list of the studies obtained through MEDLINE were included. As a result, 27 articles were selected. The results were inconsistent, 19 papers reporting changes in the N-acetyl aspartate levels, while 8 reported no change. Methodological analysis led to the conclusion that the discrepancy may be due the following factors: (i) number of participants; (ii) variation in the clinical and demographic characteristics of the groups; (iii) little standardization of the acquisition parameters of spectroscopy. Overall, studies that fulfill strict methodological criteria show N-acetyl aspartate decrease in the frontal lobe of male schizophrenics.

Factor structure of Bech's version of the Brief Psychiatric Rating Scale in Brazilian patients

The objective of the present study was to evaluate the factor structure of Bech's version of the Brief Psychiatric Rating Scale (BPRS), translated into Portuguese. The BPRS was administered to a heterogeneous group of psychiatric inpatients (N = 98) and outpatients (N = 62) in a University Hospital. Each patient was evaluated from one to eight times. The interval between consecutive interviews was one week for the inpatients and one month for the outpatients. The results were submitted to factorial analysis. The internal consistency of the total scale and of each factor was also estimated. Factorial analysis followed by normalized orthogonal rotation (Varimax) yielded four factors: Withdrawal-Retardation, Thinking Disorder, Anxious-Depression and Activation. Internal consistency measured by Cronbach's alpha coefficient ranged from 0.766 to 0.879. The data show that the factor structure of the present instrument is similar to that of the American version of the BPRS which contains 18 items, except for the absence of the fifth factor of the latter scale, Hostile-Suspiciousness.

A structured interview guide increases Brief Psychiatric Rating Scale reliability in raters with low clinical experience

OBJECTIVE

To assess the beneficial impact of a structured interview on the reliability of BPRS ratings in raters with low clinical experience.

METHOD

Each patient was rated once a week in two separate interviews, conducted on the same day. The first interview was conducted by a rater with low clinical experience (recruited from a group of five residents in psychiatry and one clinical psychologist in training). All second interviews were conducted by the same highly experienced psychiatrist.

RESULTS

The number of items with full agreement between observers increased with the use of SIG. The value of intraclass correlation coefficients for individual items and the total score also increased, approaching reported studies with experienced raters.

CONCLUSION

These results suggest that the use of SIG reduces variability of information gathering in reliability testing of BPRS with less experienced raters.