Case Control Study
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Psychiatr. Dec 22, 2015; 5(4): 404-411
Published online Dec 22, 2015. doi: 10.5498/wjp.v5.i4.404
Comprehensive neurocognitive assessment of patients with anorexia nervosa
Andrea Phillipou, Caroline Gurvich, David Jonathan Castle, Larry Allen Abel, Susan Lee Rossell
Andrea Phillipou, David Jonathan Castle, Department of Psychiatry, the University of Melbourne, Melbourne 3010, Australia
Andrea Phillipou, Larry Allen Abel, Department of Optometry and Vision Sciences, the University of Melbourne, Melbourne 3010, Australia
Andrea Phillipou, Department of Mental Health, the Austin Hospital, Melbourne 3084, Australia
Caroline Gurvich, Susan Lee Rossell, Monash Alfred Psychiatry Research Centre, Melbourne 3004, Australia
David Jonathan Castle, Susan Lee Rossell, Department of Psychiatry, St Vincent’s Hospital, Melbourne 3065, Australia
David Jonathan Castle, Faculty of Health Sciences, Australian Catholic University, Melbourne 3065, Australia
Susan Lee Rossell, Brain and Psychological Sciences Research Centre, Swinburne University of Technology, Melbourne 3122, Australia
Author contributions: Phillipou A, Gurvich C, Castle DJ, Abel LA and Rossell SL designed the research and wrote the paper; Phillipou A performed the research.
Supported by The Jack Brockhoff Foundation (3410); the Dick and Pip Smith Foundation; Australian Postgraduate Award; and the David Hay Memorial Fund Award.
Institutional review board statement: The study was granted independent ethics approval by the Human Research Ethics committees at St Vincent’s Hospital [Human Research Ethics Committee A (HREC-A)] (057/12), Austin Health [Non Drug Study Advisory Committee (NDSAC)] (H2012/04646) and The Melbourne Clinic [The Melbourne Clinic Research Ethics Committee (TMC REC)] (235). In addition, the study received expedited ethics approval from Swinburne’s Human Research Ethics Committee (SUHREC) (2012/277) and was registered with The University of Melbourne Health Sciences Human Ethics Sub-Committee (HESC) (1239068), on the basis of the prior St Vincent’s Hospital review.
Informed consent statement: All participants gave written informed consent prior to study inclusion.
Conflict-of-interest statement: Professor Castle reports grants and personal fees from Eli Lilly, grants and personal fees from Janssen-Cilag, Roche, Allergen, Bristol-Myer Squibb, Pfizer, Lundbeck, AstraZeneca and Hospira during the conduct of the study, outside the submitted work; and personal fees from Eli Lilly, Bristol-Myer Squibb, Lundbeck, Janssen-Cilag, Pfizer, Organon, Sanofi-Aventis, Wyeth, Hospira and Servier, outside the submitted work. Associate Professor Abel reports personal fees from Actelion Pharmaceuticals, Switzerland, outside the submitted work. Dr. Phillipou, Professor Rossell and Dr. Gurvich report no conflicts of interest.
Data sharing statement: Technical appendix, statistical code, and dataset available from the lead author at ap@unimelb.edu.au. No additional data are available.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: David Jonathan Castle, MD, Professor of Psychiatry, Department of Psychiatry, St Vincent’s Hospital, Level 2, 46 Nicholson St, Fitzroy, Melbourne 3065, Australia. david.castle@svha.org.au
Telephone: +61-3-92314751 Fax: +61-3-92314802
Received: June 24, 2015
Peer-review started: June 29, 2015
First decision: August 26, 2015
Revised: August 31, 2015
Accepted: October 1, 2015
Article in press: October 8, 2015
Published online: December 22, 2015
Processing time: 177 Days and 13.1 Hours
Abstract

AIM: To utilise a comprehensive cognitive battery to gain a better understanding of cognitive performance in anorexia nervosa (AN).

METHODS: Twenty-six individuals with AN and 27 healthy control participants matched for age, gender and premorbid intelligence, participated in the study. A standard cognitive battery, the Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Battery, was used to investigate performance on seven cognitive domains with the use of 10 different tasks: speed of processing [Brief Assessment Of Cognition In Schizophrenia: Symbol Coding, Category Fluency: Animal Naming (Fluency) and Trail Making Test: Part A], attention/vigilance [Continuous Performance Test - Identical Pairs (CPT-IP)], working memory [Wechsler Memory Scale (WMS®-III): Spatial Span, and Letter-Number Span (LNS)], verbal learning [Hopkins Verbal Learning Test - Revised], visual learning [Brief Visuospatial Memory Test - Revised], reasoning and problem solving [Neuropsychological Assessment Battery: Mazes], and social cognition [Mayer-Salovey-Caruso Emotional Intelligence Test: Managing Emotions]. Statistical analyses involved the use of multivariate and univariate analyses of variance.

RESULTS: Analyses conducted on the cognitive domain scores revealed no overall significant difference between groups nor any interaction between group and domain score [F(1,45) = 0.73, P = 0.649]. Analyses conducted on each of the specific tasks within the cognitive domains revealed significantly slower reaction times for false alarm responses on the CPT-IP task in AN [F(1,51) = 12.80, P < 0.01, Cohen’s d = 0.982] and a trend towards poorer performance in AN on the backward component of the WMS®-III Spatial Span task [F(1,51) = 5.88, P = 0.02, Cohen’s d = -0.665]. The finding of slower reaction times of false alarm responses is, however, limited due to the small number of false alarm responses for either group.

CONCLUSION: The findings are discussed in terms of poorer capacity to manipulate and process visuospatial material in AN.

Keywords: Cognition, Eating disorder, Body image, Spatial processing, Short-term memory

Core tip: The findings of this study suggest that individuals with anorexia nervosa (AN) have largely intact cognitive performance, which notably differs to the cognitive profile of other psychiatric illnesses, such as schizophrenia, bipolar disorder and major depressive disorder, which are all associated with significant cognitive deficits. However, a trend for AN participants to perform poorer on the backward component of a spatial span task was revealed. This suggests a poorer capacity to process and manipulate visuospatial information in AN, which may be related to the distortions of body image experienced by these individuals.