Cognitive impairment in anorexia nervosa is not due to depressed mood

Maternal Separation in ABA Rats Promotes Cell Proliferation in the Dentate Gyrus of the Hippocampus

Anorexia nervosa (AN) is a serious eating disorder characterized by self-starvation and excessive weight loss. Several studies support the idea that life stressors during the postnatal period could play a pivotal role in the pathogenesis of AN, underlying the multifactorial etiology of this disease. The activity-based anorexia (ABA) animal model mimics core features of the mental disorder, including severe food restriction, weight loss, and hyperactivity. Previous results obtained in our lab showed that maternal separation (MS) induces behavioral changes in anorexic-like ABA rats in a sexually dimorphic way: in females, the MS promoted hyperactivity and a less anxious-like phenotype in ABA animals; in males, instead, the MS attenuated the anxiolytic effect of the ABA protocol. These results led us to investigate the effect of the MS on brain areas involved in the control of the anxiety-like behavior. We focused our attention on the adult hippocampal neurogenesis, a process involved in the response to environmental stimuli and stressful condition. We analyzed the volume of the whole hippocampus and the proliferation rate in the dentate gyrus (DG) by quantifying Ki67-cells density and characterizing neuronal phenotype (DCX) and glial cells (GFAP) with double-fluorescence technique. The results obtained showed that only in maternally separated anorexic rats there is an increase of proliferation in DG, underlying the presence of a synergic effect of MS and ABA that boost the proliferation of new neurons and glia progenitors in a more evident way in females in comparison to males.

A further assessment of decision-making in anorexia nervosa

Objective:

Anorexia nervosa (AN) may be associated with impaired decision-making. Cognitive processes underlying this impairment remain unclear, mainly because previous assessments of this complex cognitive function were completed with a single test. Furthermore, clinical features such as mood status may impact this association. We aim to further explore the hypothesis of altered decision-making in AN.

Method:

Sixty-three adult women with AN and 49 female controls completed a clinical assessment and were assessed by three tasks related to decision-making [Iowa Gambling Task (IGT), Balloon Analogue Risk Task (BART), Probabilistic Reversal Learning Task (PRLT)].

Results:

People with AN had poorer performance on the IGT and made less risky choices on the BART, whereas performances were not different on PRLT. Notably, AN patients with a current major depressive disorder showed similar performance to those with no current major depressive disorder.

Conclusion:

These results tend to confirm an impaired decision making-process in people with AN and suggest that various cognitive processes such as inhibition to risk-taking or intolerance of uncertainty may underlie this condition Furthermore, these impairments seem unrelated to the potential co-occurent major depressive disorders.

Are Weight Status and Cognition Associated? An Examination of Cognitive Development in Children and Adolescents with Anorexia Nervosa 1 Year after First Hospitalisation

Objective

The aim of this study was to characterise the association between the cognitive profile and weight restoration in children and adolescents with anorexia nervosa.

Methods

The study was a longitudinal, matched case–control, multicentre study. An assessment of cognitive functions was conducted by using the Wechsler Intelligence Scale for Children–III/the Wechsler Adult Intelligence Scale–III, the Test of Memory and Learning–second edition, Trail Making Tests A and B, the Rey–Osterrieth Complex Figure Test and the Cambridge Neuropsychological Test Automated Battery.

Results

One hundred twenty individuals, 60 patients with anorexia nervosa with mean age of 14.65 (SD 1.820) years and 60 healthy controls with mean age of 14.76 (SD 1.704) years, participated. No association was found between weight recovery and cognitive functions. However, a significant increase in motor speed was found in Trail Making Test A (p = 0.004), Reaction Time (RTI) five‐choice movement time (p = 0.002) and RTI simple movement time (p = 0.011), resulting in a normalisation corresponding to that found in healthy controls. Furthermore, a significantly lower score in the perceptual organization index (p = 0.029) was found at follow‐up.

Conclusions

Weight recovery appears not to be associated with cognition. Copyright © 2016 The Authors European Eating Disorders Review published by Eating Disorders Association and John Wiley & Sons Ltd

Does depression matter in neuropsychological performances in anorexia nervosa? A descriptive review

OBJECTIVE

This review aims to examine the impact of depressive symptoms on the assessment of cognitive flexibility, central coherence, and decision-making in individuals with anorexia nervosa (AN).

METHOD

An online search was carried out using PubMed and PsycInfo. Articles were selected for review if they were published in English between 1990 and 2014 and used the Wisconsin Card Sorting Test, the Trail Making Task parts A and B, the Brixton Test, the Rey-Osterrieth Complex Figure Test, and/or the Iowa Gambling Task.

RESULTS

Sixty-two studies were included. Thirty (48%) of the studies statistically assessed the association between depression and neurocognition in AN versus healthy controls. Where significant correlations were found, it became clear that the more serious the depression, the greater the neuropsychological impairment. Only six (10%) studies examined whether increased depressive symptoms were able to eliminate the differences between individuals with AN and healthy controls, and one study found that depressive symptoms did eliminate group differences in cognitive flexibility and decision-making.

DISCUSSION

Only a subgroup of articles on neuropsychology in AN adjusted for depression. However, given the role of depression that some articles suggest, future studies should pay closer attention to the evaluation of this potential confounder.

Neuropsychological function in patients with anorexia nervosa or bulimia nervosa

OBJECTIVE

This study explored the neuropsychological performance of patients diagnosed with anorexia nervosa (AN) or bulimia nervosa (BN) compared with healthy controls (HCs). An additional aim was to investigate the effect of several possible mediators on the association between eating disorders (EDs) and cognitive function.

METHOD

Forty patients with AN, 39 patients with BN, and 40 HCs who were comparable in age and education were consecutively recruited to complete a standardized neuropsychological test battery covering the following cognitive domains: verbal learning and memory, visual learning and memory, speed of information processing, visuospatial ability, working memory, executive function, verbal fluency, attention/vigilance, and motor function.

RESULTS

The AN group scored significantly below the HCs on eight of the nine measured cognitive domains. The BN group also showed inferior performance on six cognitive domains. After adjusting for possible mediators, the nadir body mass index (lowest lifetime BMI) and depressive symptoms explained all findings in the BN group. Although this adjustment reduced the difference between the AN and HC groups, the AN group still performed worse than the HCs regarding verbal learning and memory, visual learning and memory, visuospatial ability, working memory, and executive functioning.

DISCUSSION

Patients with EDs scored below the HCs on several cognitive function measures, this difference being most pronounced for the AN group. The nadir BMI and depressive symptoms had strong mediating effects. Longitudinal studies are needed to identify the importance of weight restoration and treatment of depressive symptoms in the prevention of a possible cognitive decline.

Comparison in decision-making between bulimia nervosa, anorexia nervosa, and healthy women: influence of mood status and pathological eating concerns

BACKGROUND

Decision-making is reported to be impaired in anorexia nervosa (AN) and bulimia nervosa (BN), but the influence of mood status, pathophysiological eating, and weight concerns on the performance of decision-making ability between AN and BN is still unclear. The aims of this study were to investigate differential impairments in the decision-making process between AN, BN, and healthy controls (HC), and secondly, to explore the role of mood status, such as anxiety, depression, pathological eating, and weight concerns, in decision-making ability.

METHODS

Patients suffering from AN (n = 22), BN (n = 36) and age-matched HC (n = 51) were assessed for their decision-making abilities using the Iowa Gambling Task (IGT). Self-reported questionnaires including the Eating Disorder Examination Questionnaire (EDE-Q), the Bulimia Investigatory Test, Edinburgh (BITE), the Eating Disorders Inventory, the Maudsley Obsessive-Compulsive Inventory measuring obsessive-compulsive traits, the Hospital Anxiety and Depression Scale, and the Toronto Alexithymia Scale were used to assess pathological eating concerns and attitude to feelings.

RESULTS

Significant differences in IGT performance were observed between BN and HC. Significant negative correlation was found between IGT performance and the BITE symptom subscale in AN. In BN, there was a negative correlation between the EDE-Q weight concerns subscale and IGT performance. It was also found that increased anxiety, depression, and eating/weight concerns predicted poorer decision-making.

CONCLUSION

Different patterns of association between pathological eating concerns/behaviors and performances in decision-making ability were found between AN, BN, and HC. Anxiety, depressive mood status, and eating/weight concerns were related to decision-making ability.

Cognitive profile of children and adolescents with anorexia nervosa

Objective

Few studies of cognitive functioning in children and adolescents with anorexia nervosa (AN) have been conducted. The aim of this study was to examine the neurocognitive and intelligence profile of this clinical group.

Method

The study was a matched case–control (N = 188), multi-centre study including children and adolescents with AN (N = 94) and healthy control participants (N = 94).

Results

The results suggest that Full Scale Intelligence Quotient (Wechsler Intelligence Scale for Children-III/Wechsler Adult Intelligence Scale-III) in this patient group is close to the normal population mean of 100. Individuals with AN exhibited significantly worse performance in nonverbal intelligence functions (i.e. Wechsler Intelligence Scale for Children-III/Wechsler Adult Intelligence Scale-III, Perceptual Organization Index) and in verbal memory (Test of Memory and Learning—Second Edition, Memory for Stories) and motor speed (Cambridge Neuropsychological Test Automated Battery, Simple and Choice Reaction Time) compared with healthy control participants. No significant difference in set-shifting ability (Cambridge Neuropsychological Test Automated Battery, Intra-Extra Dimensional Set Shift and Trail Making Test B) was found.

Conclusions

Inefficiency in nonverbal intelligence functions and in specific cognitive functions was found in this study of children and adolescents with AN. © 2014 The Authors. European Eating Disorders Review published by John Wiley & Sons, Ltd.

Intellectual function in patients with anorexia nervosa and bulimia nervosa

OBJECTIVE

This study aimed to examine cognitive function in individuals with anorexia nervosa (AN) and bulimia nervosa (BN) on the basis of IQ measures, indexes and subtests of the Wechsler Adult Intelligence Scale – Third Edition (WAIS-III).

METHODS

A total of 41 patients with AN, 40 patients with BN and 40 healthy controls (HC), matched for sex, age and education, were recruited consecutively to complete the WAIS-III.

RESULTS

The AN group showed a significantly lower performance than the HC group on most global measures and on eight of the 13 administered subtests. Minor differences in verbal function were detected between the BN group and the HC group.

CONCLUSION

The patients with eating disorders showed normal intellectual functions compared with the normative population. However, the AN group displayed a consistently lower performance than the matched HC group, which performed above normative means. The BN group performed at a level between that of the AN and HC groups.

Is impaired set-shifting a feature of "pure" anorexia nervosa? Investigating the role of depression in set-shifting ability in anorexia nervosa and unipolar depression

Impaired set-shifting has been reported in patients with anorexia nervosa (AN) and in patients with affective disorders, including major depression. Due to the prevalent comorbidity of major depression in AN, this study aimed to examine the role of depression in set-shifting ability. Fifteen patients with AN without a current comorbid depression, 20 patients with unipolar depression (UD) and 35 healthy control participants were assessed using the Trail Making Test (TMT), the Wisconsin Card Sorting Test (WCST) and a Parametric Go/No-Go Test (PGNG). Set-shifting ability was intact in patients with AN without a comorbid depression. However, patients with UD performed significantly poorer in all three tasks compared to AN patients and in the TMT compared to healthy control participants. In both patient groups, set-shifting ability was moderately negatively correlated with severity of depressive symptoms, but was unrelated to BMI and severity of eating disorder symptoms in AN patients. Our results suggest a pivotal role of comorbidity for neuropsychological functioning in AN. Impairments of set-shifting ability in AN patients may have been overrated and may partly be due to comorbid depressive disorders in investigated patients.

Decision-making and planning in full recovery of anorexia nervosa

OBJECTIVE

Based on findings of persisting neuropsychological impairments in women recovered from anorexia nervosa (rec AN), this study examined decision-making and planning, for achieving a desired goal, as central executive functions in a large sample of rec AN. The definition of recovery included physiological, behavioral, and psychological variables.

METHOD

A total of 100 rec AN women were compared to 100 healthy women, 1:1 matched for age and educational level. Decision-making was assessed with the Iowa Gambling Task and planning with the Tower of London. Expert interviews and self-ratings were used for assessing the inclusion/exclusion criteria and control variables.

RESULTS

Compared to healthy controls, rec AN women were better in decision-making and worse in planning even after considering control variables.

DISCUSSION

This study does not support results from other studies showing that rec AN participants perform better in decision-making. Results from this study show that planning is impaired even after full recovery from AN.

Estimated intelligence quotient in anorexia nervosa: a systematic review and meta-analysis of the literature

BACKGROUND

It has been hypothesised that people with anorexia nervosa have a higher intelligence quotient (IQ) level than the general population. The purpose of this review was to systematically appraise the research into reported IQ levels in people with anorexia nervosa.

METHODS

A search using the terms intelligence quotient, IQ, intelligence, cognition, eating disorders and anorexia was conducted in electronic databases only.

RESULTS

In all, 30 peer-reviewed studies written in English that used well established measures of intelligence quotient (the National Adult Reading Test and Wechsler Intelligence Scales) were identified. This review established that people with anorexia nervosa score 10.8 units and 5.9 units above the average intelligence quotient of the normative population on the National Adult Reading Test and Wechsler Intelligence Scales, respectively. An association was found between Body Mass Index and intelligence quotient, as measured by the National Adult Reading Test.

CONCLUSIONS

More studies including other eating disorder categories and recovered people are needed to explore important questions regarding the role of the intelligence quotient in treatment response.

Predictors of neuropsychological recovery in treatment for anorexia nervosa

Previous research indicates that individuals with Anorexia Nervosa (AN) often experience some degree of neuropsychological dysfunction. Although most aspects of cognition improve with treatment, factors that predict neuropsychological improvement remain elusive. The present study investigated whether cognitive reserve, the estimated level of premorbid cognitive functioning, and AN subtype predicted neuropsychological improvement during inpatient treatment for AN. Neuropsychological functioning was assessed pre- and post-hospitalization in 28 women with AN (18 with restricting type and 10 with binge-eating/purging type), and cognitive reserve was estimated at admission using a word reading test. Level of cognitive reserve and AN subtype were both significant predictors of neuropsychological improvement in this sample. Cognitive reserve was significantly associated with improvements in verbal memory, semantic fluency, basic auditory attention and visuospatial construction. Participants with AN binge-eating/purging type demonstrated significantly greater neuropsychological improvement during treatment than did participants with AN restricting type. Information about cognitive reserve and AN subtype may provide clinicians with valuable prognostic information and help guide treatment.

In first presentation adolescent anorexia nervosa, do cognitive markers of underweight status change with weight gain following a refeeding intervention?

OBJECTIVE

To determine the nature and severity of cognitive functioning impairment in adolescent anorexia nervosa (AN) when underweight and following weight gain.

METHOD

In 37 first admission adolescent (12-18 years) AN patients and 45 matched controls, general cognitive functions were assessed at baseline and follow-up using the IntegNeuro-computerized battery. AN participants were tested between days 3 and 10 of their admission when underweight, with retesting conducted after weight restoration.

RESULTS

When underweight, AN participants performed more poorly than controls on sensori-motor speed tasks and exhibited a susceptibility to interference, but had superior working memory. Once the weight is restored, individuals significantly improved relative to their own performance. Relative to controls, they were significantly faster on attention and executive function tasks, exhibited superior verbal fluency, working memory, and a significantly superior ability to inhibit well-learnt responses.

DISCUSSION

Cognitive impairments in adolescent AN appear to normalize with refeeding and weight gain.

Implications of starvation-induced change in right dorsal anterior cingulate volume in anorexia nervosa

OBJECTIVE

Converging evidence suggests a role for the anterior cingulate cortex (ACC) in the pathophysiology of anorexia nervosa (AN). This study sought to determine whether ACC volume was affected by starvation in active AN and, if so, whether this had any clinical significance.

METHOD

Eighteen patients with active AN and age- and gender-matched normal controls underwent magnetic resonance imaging (MRI). Sixteen patients (89%) with AN had intelligence quotients (IQ) testing at intake, 14 (78%) had repeat MRIs after weight normalization, and 10 (56%) had outcome data at 1-year posthospitalization.

RESULTS

Right dorsal ACC volume was significantly reduced in active AN patients versus controls and was correlated with lower performance IQ. While ACC normalization occurred with weight restoration, smaller change in right dorsal ACC volume prospectively predicted relapse after treatment.

CONCLUSION

Reduced right dorsal ACC volume during active AN relates to deficits in perceptual organization and conceptual reasoning. The degree of right dorsal ACC normalization during treatment is related to outcome.

Central coherence in eating disorders: a systematic review

BACKGROUND

This review systematically appraised the research evidence for local versus global information processing to test the hypothesis that people with eating disorders (ED) had weak central coherence.

METHOD

Searches on Medline, EMBASE, PsycINFO and ISI Web of Science databases were conducted in November 2006 and subsequently updated in September 2007. Each search was conducted in two steps: (1) neuropsychological tasks measuring central coherence and (2) words related to cognitive functioning in eating disorders. Data were summarized in a meta-analysis if the number of studies for a given test was >5.

RESULTS

Data were extracted from 16 studies. Meta-analyses were conducted for four tasks obtaining moderate effect sizes. The majority of studies found global processing difficulties across the ED spectrum. The results are less clear regarding local processing.

CONCLUSIONS

People with ED have difficulties in global processing. It is less certain as to whether they have superior local processing. Currently, there is insufficient evidence to refute the weak central coherence hypothesis.

Cognitive function and brain structure in females with a history of adolescent-onset anorexia nervosa

OBJECTIVE

Abnormalities in cognitive function and brain structure have been reported in acutely ill adolescents with anorexia nervosa, but whether these abnormalities persist or are reversible in the context of weight restoration remains unclear. Brain structure and cognitive function in female subjects with adolescent-onset anorexia nervosa assessed at long-term follow-up were studied in comparison with healthy female subjects, and associations with clinical outcome were investigated.

PATIENTS AND METHODS

Sixty-six female subjects (aged 21.3 +/- 2.3 years) who had a diagnosis of adolescent-onset anorexia nervosa and treated 6.5 +/- 1.7 years earlier in a tertiary care hospital and 42 healthy female control subjects (aged 20.7 +/- 2.5 years) were assessed. All participants underwent a clinical examination, magnetic resonance brain scan, and cognitive evaluation. Clinical data were analyzed first as a function of weight recovery (n = 14, <85% ideal body weight; n = 52, >or=85% ideal body weight) and as a function of menstrual status (n = 18, absent/irregular menses; n = 29, oral contraceptive pill; n = 19, regular menses). Group comparisons were made across structural brain volumes and cognitive scores.

RESULTS

Compared with control subjects, participants with anorexia nervosa who remained at low weight had larger lateral ventricles. Twenty-four-hour urinary free-cortisol levels were positively correlated with volumes of the temporal horns of the lateral ventricles and negatively correlated with volumes of the hippocampi in clinical participants. Participants who were amenorrheic or had irregular menses showed significant cognitive deficits across a broad range of many domains.

CONCLUSIONS

Female subjects with adolescent-onset anorexia nervosa showed abnormal cognitive function and brain structure compared with healthy individuals despite an extended period since diagnosis. To our knowledge, this is the first study to report a specific relationship between menstrual function and cognitive function in this patient population. Possible mechanisms underlying neural and cognitive deficits with anorexia nervosa are discussed. Additional examination of the effects of estrogen on cognitive function in female subjects with anorexia nervosa is necessary.

Stability of neuropsychological performance in anorexia nervosa

INTRODUCTION

We investigated the stability of neuropsychological performance and eating disorder (EDO) symptoms before, immediately after, and 2 years after inpatient treatment. We also examined relationships between neuropsychological and EDO measures.

METHODS

Sixteen women who were admitted for inpatient treatment of anorexia nervosa participated in three evaluations: (1) at admission to the hospital, (2) at discharge, and (3) at a follow-up exam approximately two years after discharge.

RESULTS

Body mass index increased significantly from each testing session to the next. Endorsement of eating disorder symptoms was significantly decreased at discharge and at follow-up compared to admission. In terms of cognitive performance, total scores on a brief neuropsychological battery (RBANS) were significantly greater at follow-up than at admission. We found no relationships between EDO symptoms and cognitive function at any of the three sessions.

CONCLUSIONS

The current findings suggest that EDO symptoms and cognitive performance in anorexia nervosa patients can show improvement as long as two years after hospitalization, but there is no evidence that EDO symptoms are related to neuropsychological performance.

Neuropsychological study of underweight and "weight-recovered" anorexia nervosa compared with bulimia nervosa and normal controls

OBJECTIVE

To compare executive, memory and visuospatial functioning of DSM-IV anorexia nervosa (AN), bulimia nervosa (BN), and normal controls (NC).

METHOD

A comparison of women involving: (i) 16 AN with body mass indices (BMI) < or = 17.5 kg/m(2); (ii) 12 AN with BMI > 18.5 kg/m(2) for at least 3 months; (iii) 13 BN; and (iv) 16 NC participants was performed with groups of similar age and intelligence. Groups were assessed with EDE-12, MADRS, HAMA, Cognitive Drug Research (CDR) battery, and Bechara tasks.

RESULTS

Significant impairments in CDR Power of Attention were present in underweight AN and BN participants. CDR Morse Tapping was significantly impaired in all clinical groups. The BN and weight-recovered AN groups were significantly impaired on CDR immediate word recall. The BN group alone was significantly impaired on CDR delayed word recall.

CONCLUSION

Attentional impairment is similar in AN and BN. Impaired motor tasks in AN persist after "weight-recovery" and are similar to impairments in BN. BN may be discriminated from AN on word recall.

Neuropsychologische Beeinträchtigungen und kognitive Verarbeitung von Essensreizen bei Anorexia nervosa

Zusammenfassung. Essstörungen stellen eine wichtige psychiatrische Behandlungsindikation dar. Es ist bekannt, dass bei diesen Erkrankungen auch klinisch relevante kognitive Defizite und Auffälligkeiten in der Informationsverarbeitung bestehen, die im Alltag der PatientInnen zu Beeinträchtigungen führen. Insbesondere im Hinblick auf die schwierige und langwierige Behandlung und hohen Rückfallquoten dieser Patientengruppe ist die Berücksichtigung dieser kognitiven Besonderheiten in der Therapie von Essstörungen wichtig. Der vorliegende Artikel beschreibt neurokognitive Auffälligkeiten bei Anorexia nervosa (AN) in verschiedenen relevanten Funktionsbereichen. Im zweiten Teil der Arbeit werden aktuelle Verhaltens- und Bildgebungsstudien zur Verarbeitung von nahrungsrelevanten Stimuli dargestellt.

Available pharmacological treatments for anorexia nervosa

Currently, no medications are approved by the FDA for the treatment of anorexia nervosa (AN). However, there are several promising pharmacological targets. Treatment includes a weight restoration and a weight maintenance phase and different pharmacological treatments may be useful in one phase, but not the other. Although cyproheptadine has some modest benefit during the weight restoration phase, it is not widely used. Fluoxetine administered during the weight maintenance phase decreases relapse rate. The medications currently being most widely studied are the atypical antipsychotics, particularly olanzapine. Emerging evidence suggests that some AN patients have psychotic symptoms that may respond to antipsychotic agents. There are promising case reports and open-label studies of the atypical antipsychotics, but as yet, no randomised, placebo-controlled, double-blind studies have been reported. Additional novel treatment approaches are urgently needed for this group of severely ill patients who have a high premature mortality rate.

Neuropsychological investigation of decision-making in anorexia nervosa

Anorexia nervosa (AN) could be considered a form of obsessive-compulsive disorder in which an impairment of the cognitive domain related to decision-making was found. We explored this function in AN patients, as well as possible differences between restricting type and binge/purge type, with the aim of examining the hypothesis that AN is part of the obsessive-compulsive spectrum. Decision-making was assessed in 59 inpatients with AN and 82 control subjects using the Gambling task, which simulates real-life decision-making by assessing the ability to balance immediate rewards against long-term negative consequences. We confirmed the supposed deficit of decision-making in AN. However, restricting and binge eating/purge subtypes showed different patterns of decision-making impairment. Poor performance on the Gambling task is not a mere consequence of starvation and does not appear to be related to illness severity. The decision-making deficiency that some AN patients show is linked to those individual features that contribute to the phenomenological expression of the disorder.