Neuropsychiatry

Annotated Abstracts of Journal Articles
2014, 4th Quarter

Neuropsychiatry

Annotations by Nicholas Kontos, MD
December 2014

  1. Insular cortex: structural and functional neuroanatomy
  2. The role of alexithymia in the development of functional motor symptoms (conversion disorder)
  3. Attention! A good bedside test for delirium?

 

PUBLICATION #1 — Neuropsychiatry
Insular cortex: structural and functional neuroanatomy
Shura RD, Hurley RA, Taber KH
J Neuropsychiatry Clin Neurosci 2014 Fall; 26(4):iv-282 [“Windows to the Brain” column; link is to full text article]

ANNOTATION (Nicholas Kontos)

The Finding:  While the existence of the insula/insular cortex/island of Reil has been known for about a century, it is only lately being studied rigorously and vigorously. This paper provides a nice graphical and textural summary of these findings. The anatomy, connectivity, and some neuropsychiatric implications (in frontotemporal dementia and, to a lesser degree, schizophrenia) are summarized.

Strengths and Weaknesses:  Excellent figures and a succinct summary of a large and complex literature that clinicians are unlikely to come across on their own. [Incidentally, the “Windows to the Brain” section of the Journal of Neuropsychiatry and Clinical Neuroscience features this sort of review every issue.] Still a relatively early area of study, the conclusions drawn here about the insula’s functions might be unsatisfying to some (e.g., one section’s dense discussion is summarized by saying “more research is needed, and sources seem to agree that the insula is involved in complex and multimodal functions”).

Relevance: With increasing attention to “interoception” as a significant neuropsychiatric player in psychosomatic research, the insula, as a candidate neural network hub for that activity, warrants our attention as a field.

INTRODUCTION OF FULL TEXT ARTICLE
(No abstract available)

Although the insula was described by Brodmann and von Economo early in the 20th century, there has been a recent surge in interest in this area. Comprising only approximately 2% of cortical surface area, research over the last two decades supports participation of the insular cortex in a wide range of functional circuits. There is growing evidence that the insula is important to neuropsychiatric disorders, especially in relation to dysfunctions involving higher order cognitive, emotional, and social networks. The insula’s primary role is believed to be that of multimodal integration. With this increased research attention, knowledge regarding the insula’s role in clinical syndromes has also increased.

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PUBLICATION #2 — Neuropsychiatry
The role of alexithymia in the development of functional motor symptoms (conversion disorder)
Demartini B, Petrochilos P, Ricciardi L, Price G, Edwards MJ, Joyce E
J Neurol Neurosurg Psychiatry 2014; 85(10):1132-7

ANNOTATION (Nicholas Kontos)

The Finding: Alexithymia appears to be significantly overrepresented in patients with conversion movement disorders relative to both patients with “organic” movement disorders and healthy controls.

Strengths and Weaknesses:  The introduction nicely brings conversion disorder and alexithymia into the DSM-5 era. The discussion section attempts, intriguingly if not seamlessly (e.g., hard to tell if/whether the authors consider conversion disorder distinct from other forms of “somatization”) to weave together alexithymia and a neurobiological/cognitive model of conversion in a way that might have practical implications for treatment selection. As with many studies of conversion, there is a question of whether groups with one type of neurological presentation are comparable to others. Here, for instance, there is a between-groups issue regarding the study of these movement disorder patients versus previous studies which have largely found unremarkable differences in alexithymia rates in PNES vs. epilepsy subjects. There is also a within-group issue in this study; as the authors point out, their “organic” movement disorder group contained a hugely disproportionate (>80%) number of dystonia patients that did not match well with the conversion patient group, or broadly with usual movement disorder populations.

Relevance: This paper studies and discusses alexithymia in conversion disorder in a way that accommodates the supposed etiologic neutrality of DSMs III onward, and the removal of the inciting stressor criterion from DSM-5 conversion disorder. It raises interesting questions about not only the further study of conversion disorder, but also its treatment.

ABSTRACT (PubMed)

Background: The mechanisms leading to the development of functional motor symptoms (FMS) are of pathophysiological and clinical relevance, yet are poorly understood.

Aim: The aim of the present study was to evaluate whether impaired emotional processing at the cognitive level (alexithymia) is present in patients affected by FMS. We conducted a cross-sectional study in a population of patients with FMS and in two control groups (patients with organic movement disorders (OMD) and healthy volunteers).

Methods: 55 patients with FMS, 33 patients affected by OMD and 34 healthy volunteers were recruited. The assessment included the 20-item Toronto Alexithymia Scale (TAS-20), the Montgomery-Asberg Depression Rating Scale, the Reading the Mind in the Eyes’ Test and the Structured Clinical Interview for Personality Disorders.

Results: Alexithymia was present in 34.5% of patients with FMS, 9.1% with OMD and 5.9% of the healthy volunteers, which was significantly higher in the FMS group (χ(2) (2)=14.129, p<0.001), even after controlling for the severity of symptoms of depression. Group differences in mean scores were observed on both the difficulty identifying feelings and difficulty describing feelings dimensions of the TAS-20, whereas the externally orientated thinking subscale score was similar across the three groups. Regarding personality disorder, χ(2) analysis showed a significantly higher prominence of obsessive-compulsive personality disorder (OCPD) in the FMS group (χ(2) (2)=16.217, p<0.001) and 71.4% of those with OCPD also reached threshold criteria for alexithymia.

Conclusions: Because alexithymia is a mental state denoting the inability to identify emotions at a cognitive level, one hypothesis is that some patients misattribute autonomic symptoms of anxiety, for example, tremor, paraesthesiae, paralysis, to that of a physical illness. Further work is required to understand the contribution of OCPD to the development of FMS.

 

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PUBLICATION #3 — Neuropsychiatry
Attention! A good bedside test for delirium?
O’Regan NA, Ryan DJ, Boland E, et al
J Neurol Neurosurg Psychiatry 2014; 85(10):1122-31

ANNOTATION (Nicholas Kontos)

The Finding
Simple attention screening (months of year backwards) is a sensitive and surprisingly specific detector of delirium in hospitalized (non-intensive care) populations. It is enhanced by combining with screens for subjective confusion and/or a visuospatial attention task.

Strengths and Weaknesses:  This article highlights the continued problems that exist in delirium detection in the general hospital setting, reviews proposed remedies, and makes a convincing argument for a much simpler solution than has been referred previously. The study design was audacious (all assessments of the >200 pts took place on the same day; this included screening followed by second screening with the CAMb, followed by psychiatric assessment) but appears to have been carried out rigorously. The authors do an excellent job of identifying the potential limiting factors of the study. The biggest quibble is that attention is far from a specific delirium finding, and probably ought not be taken as such in a cross sectional assessment. However, as noted by the authors, very, very few patients with documented dementia in this study did not have delirium. The fact that patients with cognitive impairment are more susceptible to delirium may mitigate the usual insensitivity of attentional impairment as a diagnostic screen. Also, technically, months of the year backwards is not a pure attention screen as it employs working memory as well (as opposed to forwards digit span). However, for the purposes of this study, it does the job.

Relevance: There may be simpler correctives to the miserable state of delirium detection in the general hospital than is currently thought. This paper will not add much to an experienced psychiatrist’s diagnostic toolkit, but may have quality improvement implications.

ABSTRACT (PubMed)

Background: Routine delirium screening could improve delirium detection, but it remains unclear as to which screening tool is most suitable. We tested the diagnostic accuracy of the following screening methods (either individually or in combination) in the detection of delirium: MOTYB (months of the year backwards); SSF (Spatial Span Forwards); evidence of subjective or objective ‘confusion’.

Methods: We performed a cross-sectional study of general hospital adult inpatients in a large tertiary referral hospital. Screening tests were performed by junior medical trainees. Subsequently, two independent formal delirium assessments were performed: first, the Confusion Assessment Method (CAM) followed by the Delirium Rating Scale-Revised 98 (DRS-R98). DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, fourth edition) criteria were used to assign delirium diagnosis. Sensitivity and specificity ratios with 95% CIs were calculated for each screening method.

Results: 265 patients were included. The most precise screening method overall was achieved by simultaneously performing MOTYB and assessing for subjective/objective confusion (sensitivity 93.8%, 95% CI 82.8 to 98.6; specificity 84.7%, 95% CI 79.2 to 89.2). In older patients, MOTYB alone was most accurate, whereas in younger patients, a simultaneous combination of SSF (cut-off 4) with either MOTYB or assessment of subjective/objective confusion was best. In every case, addition of the CAM as a second-line screening step to improve specificity resulted in considerable loss in sensitivity.

Conclusions: Our results suggest that simple attention tests may be useful in delirium screening. MOTYB used alone was the most accurate screening test in older people.

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