Are neuropsychological deficits trait markers in OCD?
ABSTRACT Neuropsychological deficits are potential endophenotype markers. In obsessive-compulsive disorder (OCD), there is impairment in executive functions and nonverbal memory. However, studies have largely examined neuropsychological functioning in patients during the symptomatic phase. The state independent nature of neuropsychological deficits in OCD is not established. For neuropsychological deficits to be endophenotype markers, they have to be state-independent. We compared neuropsychological functions in recovered OCD patients with matched healthy controls.
We assessed 30 recovered DSM-IV OCD patients without any concurrent comorbidity or lifetime history of schizophrenia, bipolar disorder, tics and alcohol/substance abuse and 30 healthy controls individually matched for age, sex and education. They were assessed on different neuropsychological dimensions: attention, executive function, memory and intelligence. For between-group comparisons, we employed univariate analyses, and to identify neuropsychological variables that differentiate cases and controls, we used backward conditional logistic regression for matched case-control design.
Patients in the recovered phase of the illness had significant deficits in tests of set-shifting ability, alternation, response inhibition and nonverbal memory but had intact performance in other tests. In the logistic regression, scores on the Wisconsin Card Sorting Test 'categories completed' and the Rey's Complex Fig. Test 'delayed recall' were significant after controlling for the possible confounding effects of age and education. There was no correlation between illness-related variables and neuropsychological deficits.
Deficits in certain executive functions and nonverbal memory are possibly state independent. Neuropsychological deficits are possibly candidate endophenotype markers for OCD and may help clarify genetic contributions. Future studies should evaluate unaffected siblings to establish deficits are endophenotype markers. Prospective studies with serial measurements of cognitive deficits are also needed to assess whether these deficits are cumulative with the progression of illness.
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ABSTRACT: Obsessive-compulsive disorder (OCD) is a serious and often chronically disabling condition. The current dominant model of OCD focuses on abnormalities in prefrontal-striatal circuits that support executive function (EF). While there is growing evidence for EF impairments associated with OCD, results have been inconsistent, making the nature and magnitude of these impairments controversial. The current meta-analysis uses random-effects models to synthesize 110 previous studies that compared participants with OCD to healthy control participants on at least one neuropsychological measure of EF. The results indicate that individuals with OCD are impaired on tasks measuring most aspects of EF, consistent with broad impairment in EF. EF deficits were not explained by general motor slowness or depression. Effect sizes were largely stable across variation in demographic and clinical characteristics of samples, although medication use, age, and gender moderated some effects.03/2015; 3(2):301-330. DOI:10.1177/2167702614534210
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ABSTRACT: The inconsistent nature of the neuropsychology literature pertaining to obsessive-compulsive disorder (OCD) has long been recognized. However, individual studies, systematic reviews, and recent meta-analytic reviews were unsuccessful in establishing a consensus regarding a disorder-specific neuropsychological profile. In an attempt to identify methodological factors that may contribute to the inconsistency that is characteristic of this body of research, a systematic review of methodological factors in studies comparing OCD patients and non-psychiatric controls on neuropsychological tests was conducted. This review covered 115 studies that included nearly 3500 patients. Results revealed a range of methodological weaknesses. Some of these weaknesses have been previously noted in the broader neuropsychological literature, while some are more specific to psychiatric disorders, and to OCD. These methodological shortcomings have the potential to hinder the identification of a specific neuropsychological profile associated with OCD as well as to obscure the association between neurocognitive dysfunctions and contemporary neurobiological models. Rectifying these weaknesses may facilitate replicability, and promote our ability to extract cogent, meaningful, and more unified inferences regarding the neuropsychology of OCD. To that end, we present a set of methodological recommendations to facilitate future neuropsychology research in psychiatric disorders in general, and in OCD in particular. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.Psychiatry Research 04/2015; DOI:10.1016/j.psychres.2015.04.025 · 2.68 Impact Factor
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ABSTRACT: Background: Evolutionary theories link pathogenesis of psychiatric disorders with anomalous cerebral asymmetry. Asymmetry assessment using line bisection task performance is less examined in obsessive compulsive disorder (OCD). Thus, we examined anomalous cerebral asymmetry in OCD using line bisection task. Method: 30 OCD patients and 30 matched healthy controls were examined using a reliable and valid two-hand line bisection task (LBS). LBS task performance was assessed by raters blind to subject status with good inter-rater reliability. The comparative profiles of LBS scores were analyzed using analysis of covariance. Correlation between clinical correlates and LBS scores were assessed using Spearman correlation analysis. Results: OCD patients bisected significantly less number of lines to left than controls using right-hand (F=7.94; p=0.007) as well as left-hand (F=8.67; p=0.005). There was a significant right ward deviation in patients than controls (F=13.19; p=0.001). Rightward deviation had significant negative correlation with CGI-improvement (rho= - 0.37; p=0.04) and positive correlation with change in YBOCS-score (rho=0.34; p=0.01) and baseline YBOCS-score (rho=0.38; p=0.008). Conclusion: Study findings suggest abnormal right hemisphere function in OCD. This anomalous cerebral asymmetry may be a predictor of good treatment response. Prospective studies need to examine the utility of LBS task in predicting the outcome in OCD.Acta Neuropsychiatrica 03/2015; DOI:10.1017/neu.2015.23 · 0.61 Impact Factor