Obsessive-compulsive disorder symptom dimensions show specific relationships to psychiatric comorbidity

Sex differences in neural responses to disgusting visual stimuli: implications for disgust-related psychiatric disorders

BACKGROUND

A majority of patients with disgust-related psychiatric disorders such as animal phobias and contamination-related obsessive-compulsive disorder are women. The aim of this functional magnetic resonance imaging (fMRI) study was to examine possible sex differences in neural responses to disgust-inducing stimuli that might help explain this female predominance.

METHODS

Thirty-four healthy adult volunteers (17 women, all right-handed) were scanned while viewing alternating blocks of disgusting and neutral pictures from the International Affective Picture System. Using a partially-silent fMRI sequence, the participants rated their level of discomfort after each block of pictures. Skin conductance responses (SCR) were measured throughout the experiment. All participants completed the Disgust Scale.

RESULTS

Both women and men reported greater subjective discomfort and showed more SCR fluctuations during the disgusting picture blocks than during the neutral picture blocks. Women and men also demonstrated a similar pattern of brain response to disgusting compared with neutral pictures, showing activation in the anterior insula, ventrolateral and dorsolateral prefrontal cortices, and visual regions. Compared with men, women had significantly higher disgust sensitivity scores, experienced more subjective discomfort, and demonstrated greater activity in left ventrolateral prefrontal regions. However, these differences were no longer significant when disgust sensitivity scores were controlled for.

CONCLUSIONS

In healthy adult volunteers, there are significant sex-related differences in brain responses to disgusting stimuli that are irrevocably linked to greater disgust sensitivity scores in women. The implications for disgust-related psychiatric disorders are discussed.

Factors associated with major depressive disorder occurring after the onset of obsessive-compulsive disorder

BACKGROUND

We aimed to investigate the correlates of major depressive disorder (MDD) occurring after the onset of obsessive-compulsive disorder (OCD).

METHODS

Forty-three OCD patients who developed MDD after the onset of OCD (OCD-MDD group) and 67 OCD patients without MDD (non-MDD, NMDD group) were compared with regard to sociodemographic characteristics, clinical history, symptom severity, types of obsessions and compulsions, insight degree, comorbid axis I and axis II diagnosis and quality-of-life level.

RESULTS

The OCD-MDD group scored significantly higher on measures of obsessions, compulsions and depression severity than did the NMDD. Significantly more aggressive obsessions were identified in the OCD-MDD group than in the NMDD group. The OCD-MDD group was also significantly more likely than the NMDD group to have generalized anxiety disorder (GAD). There was no significant difference in the rate of personality disorders between the groups. The OCD-MDD group reported significantly lower levels of quality of life (QOL) in the domains of physical health, psychological health and social relationships. Depression severity was associated with obsession but not with compulsion severity. In a logistic regression model, obsession severity, presence of GAD and aggressive obsessions emerged as the factors associated with the occurrence of MDD.

LIMITATIONS

To exclude ineligible patients, we gathered the information about past mood episodes cross-sectionally.

CONCLUSIONS

These results suggest that psychopathological processes mediated by specific obsessions as well as excessive anxiety and worries may render the neurocircuities more vulnerable to the development of MDD. The occurrence of MDD in OCD cannot sufficiently be explained as a secondary complication to the disability of OCD.

Obsessive-compulsive and eating disorders: comparison of clinical and personality features

The aim of the present study was to determine whether anorexia nervosa (AN), bulimia nervosa (BN) and obsessive-compulsive disorder (OCD) share clinical and psychopathological traits. The sample consisted of 90 female patients (30 OCD; 30 AN; 30 BN), who had been consecutively referred to the Department of Psychiatry, University Hospital of Bellvitge, Barcelona. All subjects met DSM-IV criteria for those pathologies. The assessment consisted of the Maudsley Obsessive-Compulsive Inventory (MOCI), Questionnaire of obsessive traits and personality by Vallejo, Eating Attitudes Test-40 (EAT-40), Eating Disorder Inventory (EDI), and Beck Depression Inventory (BDI). ANCOVA tests (adjusted for age and body mass index) and multiple linear regression models based on obsessive-compulsiveness, obsessive personality traits and perfectionism, as independent variables, were applied to determine the best predictors of eating disorder severity. On ancova several significant differences were found between obsessive-compulsive and eating-disordered patients (MOCI, P < 0.001; EAT, P < 0.001; EDI, P < 0.001), whereas some obsessive personality traits were not eating disorder specific. A total of 16.7% OCD patients presented a comorbid eating disorder, whereas 3.3% eating disorders patients had an OCD diagnosis. In the eating disorder group, the presence of OC symptomatology was positively associated (r = 0.57, P < 0.001) with the severity of the eating disorder. The results were maintained after adjusting for comorbidity. Although some obsessive-compulsive and eating disorder patients share common traits (e.g. some personality traits especially between OCD and AN), both disorders seem to be clinically and psychopathologically different.

Obsessive-compulsive symptoms in sibling pairs concordant for obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) is a heterogeneous disorder of unknown etiology. Phenotypic studies of affected sib-pairs (SPs) may help to characterize familial components of the phenotype. To determine whether SPs affected with OCD are similar in age at onset of obsessive-compulsive symptoms (OCS), symptom dimensions and presence of tic disorders (TDs). Forty OCD siblings ranging from 13 to 59 years old were evaluated by expert psychiatrists or psychologists. Families with two or more siblings affected with OCD were recruited from several OCD clinics in Brazil. The Yale Brown Obsessive-Compulsive Scale Checklist was used to assess OCS and the severity of OCD. The OCD diagnoses were made according to the DSM-IV. The chi-square test was used to assess concordance of TD presence within SPs based on the TD frequency reported in the literature (30%). There were significantly more siblings with early-onset OCS than with late-onset OCS (P = 0.002). Age at onset of OCS correlated positively and significantly between the two members of each SP (P = 0.005). Fourteen patients (35%) were diagnosed with TDs. There was no concordance of the TD presence within the SPs. When both were male, there was a significant sibling correlation in the contamination obsessions/cleaning compulsions dimension (ICC = 0.74; P = 0.002). Similarly, when both siblings were female, they were comparable in the hoarding obsessions/compulsions dimension (ICC = 0.76; P = 0.01). Familial factors seem to contribute to specific OCD phenotypic components such as age at onset of OCS and specific dimensions. The obvious influence of gender is as yet unexplained.

Does obsessive-compulsive personality disorder belong within the obsessive-compulsive spectrum?

It has been proposed that certain Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition Axis I disorders share overlapping clinical features, genetic contributions, and treatment response and fall within an "obsessive-compulsive" spectrum. Obsessive-compulsive personality disorder (OCPD) resembles obsessive-compulsive disorder (OCD) and other spectrum disorders in terms of phenomenology, comorbidity, neurocognition, and treatment response. This article critically examines the nosological profile of OCPD with special reference to OCD and related disorders. By viewing OCPD as a candidate member of the obsessive-compulsive spectrum, we gain a fresh approach to understanding its neurobiology, etiology, and potential treatments.

The relationship between compulsive behaviour and academic achievement across the three genetic subtypes of Prader-Willi syndrome

BACKGROUND

Prader-Willi syndrome (PWS) is a genetic syndrome associated with several physical, cognitive and behavioural characteristics. For many individuals with this syndrome, compulsive behaviour is often noted in both food and non-food situations. The focus of this paper is on the non-food-related compulsions in individuals with PWS and comparing differences across the three genetic subtypes of the syndrome.

METHODS

Compulsive behaviours in 73 people with PWS were assessed using the Yale-Brown Obsessive Compulsive Scale and the Compulsive Behavior Checklist. Compulsive behaviour and its relation to IQ and academic achievement also were evaluated. Phenotypic differences were characterized for the three most common genetic subtypes of the disorder: 16 individuals with the long Type I (TI) 15q deletion, 26 individuals with the short Type II (TII) 15q deletion and 31 individuals with maternal disomy 15.

RESULTS

There appeared to be important differences between the two deletion subtypes. Specifically, individuals with the TI deletion had more compulsions regarding personal cleanliness (i.e. excessive bathing/grooming), and their compulsions were more difficult to interrupt and interfered with social activities more than the other subtypes. Individuals with the TII deletion were more likely to have compulsions related to specific academic areas (i.e. rereading, erasing answers and counting objects or numbers).

CONCLUSIONS

These findings may help clinicians and researchers identify possible intervention strategies and supports based on the behavioural phenotype associated with genetic subtype in individuals with PWS.

Symptom dimensions in obsessive-compulsive disorder: implications for the DSM-V

In the absence of definitive etiological markers of vulnerability or a unitary profile of pathophysiology for obsessive-compulsive disorder (OCD), obsessive-compulsive (OC) symptom dimensions seem to offer a fruitful point of orientation. The complex clinical presentation of OCD can be summarized using a few consistent and temporally stable symptom dimensions. These can be understood as a spectrum of potentially overlapping features that are likely to be continuous with "normal" worries and extend beyond the traditional nosological boundaries of OCD. Although the understanding of the dimensional structure of obsessive-compulsive symptoms (OCS) is still imperfect, this quantitative approach to phenotypic traits has the potential to advance our understanding of OCD and may aid in the identification of more robust endophenotypes. Preliminary data suggest that these dimensional phenotypes may be useful in studies of the natural history, genetics, neurobiology, and treatment outcome of OCD. A dimensional approach is not mutually exclusive of other methods to parse the larger spectrum of disorders related to OCD. Thus far, age-of-onset of OCS and the individual's "tic-related" status seem to be particularly useful categorical distinctions. Finally, existing assessment methods are inadequate and new dimensional scales are needed to take full advantage of a dimensional approach in clinical and population-based studies.

Bipolar and nonbipolar obsessive-compulsive disorder: a clinical exploration

Comorbidity of obsessive-compulsive disorder (OCD) in bipolar disorder is well documented. However, clinical characteristics of bipolar OCD are not well studied. The objective of the present study was to compare the clinical characteristics of bipolar and nonbipolar OCD. We chose 28 subjects with bipolar-OCD comorbidity from a sample of 80 remitted bipolar subjects (bipolar OCD) attending the outpatient services of the National Institute of Mental Health and Neurosciences, Bangalore, India, over a period of 11 months. We also recruited 78 nonbipolar OCD subjects consecutively during the same period from the OCD clinic of the institute. They underwent systematic assessment using both structured and unstructured clinical interviews and corroborative information obtained from the immediate family members and the hospital clinical charts. Bipolar OCD subjects were characterized by episodic course of OCD, high family loading for mood disorders, and comorbidity with depression, social phobia, and generalized anxiety disorder. They had less severe OCD and had somewhat different symptom profile compared with nonbipolar OCD. The OCD predated bipolar disorder in 54% of the bipolar OCD subjects; and in the remaining subjects, it had an onset during the course of bipolar disorder. Most bipolar OCD subjects reported worsening of OCD in depression (n = 22, 78%) and improvement in manic/hypomanic episodes (n = 18, 64%). Our findings suggest that OCD in those with a primary diagnosis of bipolar disorder is perhaps pathophysiologically related to bipolar disorder than to OCD. This is strongly supported by the episodic course of OCD, high familial loading for mood disorders, and worsening of OCD in depression with improvement in hypomania/mania phases. There is a need for systematic exploration of the OCD-bipolar comorbidity in both OCD and bipolar samples. Family-genetic and other neurobiological research and the prospective follow-up of bipolar and nonbipolar OCD subjects would further enhance our understanding of this complex comorbidity. The cross-sectional nature of the study based on retrospective assessment of course, the small sample size and the inclusion of only remitted bipolar subjects are the limitations of this study.

Obsessive-compulsive spectrum disorders: cross-national and ethnic issues

Epidemiological and clinical data from a variety of cultural and geographic settings on obsessive-compulsive disorder (OCD), and many of the obsessive-compulsive spectrum disorders, suggest that this is a group of disorders with a good degree of transcultural homogeneity. However, the content and themes that predominate in patients with these disorders, and the course of illness, can be shaped by cultural, ethnic, and religious experiences. Across cultures, OCD is commonly comorbid with mood, anxiety, and impulse-control disorders. However, little is known about the mechanisms by which culture and ethnicity may affect the expression of OCD and related disorders. Cross-national comparative studies exploring culturally influenced differences in clinical course, treatment outcome, including ethnogenetic differences in drug response, and prognosis are needed.

Obsessive-compulsive disorder with comorbid major depression: what is the role of cognitive factors?

Individuals with obsessive-compulsive disorder (OCD) commonly experience comorbid mood disturbances such as major depressive disorder (MDD). Previous studies that have compared OCD patients with and without MDD have revealed differences in demographic characteristics, clinical severity, and symptom presentation between these two patient groups. Previous studies have not, however, examined whether there are differences with respect to cognitive processes. The present study therefore aimed to address this gap in the literature. Eighty patients with OCD and no unipolar mood disorders were compared with 34 OCD patients with comorbid major depression on measures of OCD symptoms, cognitions, and insight, as well as on measures of depression and functional impairment. Whereas depressed OCD patients evidenced higher scores than non-depressed OCD patients on semi-idiographic measures of OCD symptoms and cognitions, this was not the case for nomothetic measures. Functional impairment and the tendency to misinterpret innocuous intrusive thoughts as significant emerged as unique predictors of depression within the entire sample of OCD patients. Results are discussed in terms of (a) the importance of semi-idiographic assessment of OCD, (b) possible explanations for the relationship between OCD symptoms, depression, and cognitive processes, and (c) the psychological treatment of comorbid OCD and MDD.

Hoarding in obsessive–compulsive disorder: Results from the OCD Collaborative Genetics Study

Hoarding behavior occurs frequently in obsessive-compulsive disorder (OCD). Results from previous studies suggest that individuals with OCD who have hoarding symptoms are clinically different than non-hoarders and may represent a distinct clinical group. In the present study, we compared 235 hoarding to 389 non-hoarding participants, all of whom had OCD, collected in the course of the OCD Collaborative Genetics Study. We found that, compared to non-hoarding individuals, hoarders were more likely to have symmetry obsessions and repeating, counting, and ordering compulsions; poorer insight; more severe illness; difficulty initiating or completing tasks; and indecision. Hoarders had a greater prevalence of social phobia and generalized anxiety disorder. Hoarders also had a greater prevalence of obsessive-compulsive and dependent personality disorders. Five personality traits were independently associated with hoarding: miserliness, preoccupation with details, difficulty making decisions, odd behavior or appearance, and magical thinking. Hoarding and indecision were more prevalent in the relatives of hoarding than of non-hoarding probands. Hoarding in relatives was associated with indecision in probands, independently of proband hoarding status. The findings suggest that hoarding behavior may help differentiate a distinct clinical subgroup of people with OCD and may aggregate in some OCD families. Indecision may be a risk factor for hoarding in these families.

Level of insight and clinical features of obsessive-compulsive disorder with and without body dysmorphic disorder

INTRODUCTION

Body dysmorphic disorder (BDD) and obsessive-compulsive disorder (OCD) have several similarities and are included among the obsessive-compulsive spectrum of disorders. However, the content of preoccupations and level of insight of BDD patients differ from OCD patients.

OBJECTIVE

To compare the level of insight regarding obsessive-compulsive symptoms (OCS) and other clinical features in OCD patients with and without comorbid BDD.

METHODS

We evaluated 103 OCD patients (n=25, comorbid BDD), according to Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria using the Structured Clinical Interview for DSM-IV, the Yale-Brown Obsessive-Compulsive Scale, the University of Sao Paulo Sensory Phenomena Scale, the Beck Depression and Anxiety Inventories, and the Brown Assessment of Beliefs Scale.

RESULTS

The study groups differed significantly on several clinical features, including level of insight. A worse level of insight regarding OCS was independently associated with the presence of comorbid BDD. Lower educational level, more psychiatric comorbidities, presence of somatic and hoarding obsessions, and presence of intrusive images were associated with BDD comorbidity, even after adjusting for possible confounders.

CONCLUSION

The presence of BDD in OCD patients is associated with poorer insight into obsessional beliefs and higher morbidity, reflected by lower educational levels and higher number of psychiatric comorbid disorders in general.

Apport actuel des neurosciences à travers une nouvelle lecture clinique du trouble obsessionnel compulsif

Obsessive-compulsive disorder (OCD), that affects 2 to 3% of the general population, is characterized by recurrent intrusive thoughts and repetitive, time-consuming behaviors. It is a severely incapacitating mental illness that causes profound impairment in psychosocial functioning and quality of life. Although the physiopathology of OCD is still far from resolved, the existence of a biological basis for OCD is now clearly established and should be interpreted from phenomenological considerations, on the one hand, and in the light of our increasing knowledge of the physiology of cortico-subcortical functional loops, on the other. In a phenomenological view, the heart of the obsessional process is the subject's underlying impression that "something is wrong". In other words, obsessions may be thought of as the permanent perception of a mistake and/or error in certain behavioral situations. Compulsions occur as behavioral responses aimed at relieving the tensions or anxiety generated by the situation. If obtained, this relief may be felt to be a form of reward. Nevertheless, it is only transient, thereby creating a feeling of considerable anxiety. This contributes to immediately reproducing the behavior in a cyclic manner, on the basis of an internal motivational state through an expectation of the reward. Therefore, it can be assumed that several malfunctioning processes are altered within the OCD: 1) error recognition; and, 2) emotion and motivation. This suggests that there is a dysfunction of the brain regions mediating these cognitive and emotional functions. Experimental neurophysiology in laboratory animals indicates the central role of the fronto-subcortical circuits originating in the orbitofrontal and anterior cingulate cortices, respectively. The orbitofrontal cortex (OFC) and ventromedial areas are involved in appraisal of the emotional and motivational values of environmental information, and in integrating the subject's prior experience, which is crucial in decision-making. The OFC also contributes to the selection, comparison and judgment of stimuli and error detection. The anterior cingulate cortex (ACC) is comprised of 1) a ventral or affective region that could keep attention on the internal emotional and motivational status and regulation of autonomic responses, and 2) a dorsal and cognitive region that serves a wide range of functions including attention, working memory, error detection, conflict monitoring, response selection, and anticipation of incoming information. Ventral striatum, that is intimately connected to the OFC and ACC, participates in the preparation, initiation and execution of behavioral responses oriented toward reward delivery following the cognitive and emotional integration of behaviorally relevant information at the cortical level. Functional imaging research in humans has shown an increased functional activity in the OFC, ACC, head of the caudate nucleus and thalamus in OCD patients. These functional abnormalities have been found in basal conditions and during provocation tests. Moreover, the therapeutic efficacy of antidepressants with preponderant serotonin-reuptake inhibiting properties and cognitive-behavioral therapies seems to be associated with a progressive reduction in activity of the OFC, ACC and the caudate nucleus. Therefore, these observations are suggestive of the responsibility of 5HT neurotransmission in the dysfunction of the frontal-subcortical loops that emanate from the OFC and ACC. However, several lines of research suggest that the dopamine system, with which 5HT interacts, may play a major role in the expression of OC symptoms. In conclusion, it seems that in OCD there is a dysfunction of the brain regions that belong to the orbitofrontal and anterior cingulate loops in view of evidence obtained from separate and complementary approaches.

Familiality of factor analysis-derived YBOCS dimensions in OCD-affected sibling pairs from the OCD Collaborative Genetics Study

BACKGROUND

Identification of familial, more homogenous characteristics of obsessive-compulsive disorder (OCD) may help to define relevant subtypes and increase the power of genetic and neurobiological studies of OCD. While factor-analytic studies have found consistent, clinically meaningful OCD symptom dimensions, there have been only limited attempts to evaluate the familiality and potential genetic basis of such dimensions.

METHODS

Four hundred eighteen sibling pairs with OCD were evaluated using the Structured Clinical Interview for DSM-IV and the Yale-Brown Obsessive Compulsive Scale (YBOCS) Symptom Checklist and Severity scales.

RESULTS

After controlling for sex, age, and age of onset, robust sib-sib intraclass correlations were found for two of the four YBOCS factors: Factor IV (hoarding obsessions and compulsions (p = .001) and Factor I (aggressive, sexual, and religious obsessions, and checking compulsions; p = .002). Smaller, but still significant, familiality was found for Factor III (contamination/cleaning; p = .02) and Factor II (symmetry/ordering/arranging; p = .04). Limiting the sample to female subjects more than doubled the familiality estimates for Factor II (p = .003). Among potentially relevant comorbid conditions for genetic studies, bipolar I/II and major depressive disorder were strongly associated with Factor I (p < .001), whereas ADHD, alcohol dependence, and bulimia were associated with Factor II (p < .01).

CONCLUSIONS

Factor-analyzed OCD symptom dimensions in sibling pairs with OCD are familial with some gender-dependence, exhibit relatively specific relationships to comorbid psychiatric disorders and thus may be useful as refined phenotypes for molecular genetic studies of OCD.

An investigation of traumatic life events and obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD), like most other psychiatric disorders, is suspected of being influenced by an interaction between life events and genes, both with regard to onset and course of illness. To date, no specific genes have been identified as playing a frequent role, and only a relatively few empirical studies have assessed the association between stressful life events (SLEs) and OCD. The present study builds on past research by examining the potential contributions from traumatic life events (TLEs) on the severity and symptom features in 265 individuals with Structured Clinical Interview for DSM-IV (SCID)-diagnosed OCD. Of these participants 54% endorsed having experienced at least one TLE in their life time. The presence of one or more TLEs was associated with increased OCD symptom severity. This relationship remained significant despite controlling for key variables including age, OCD age-of-onset, comorbidity, and depressive symptoms. In addition, obsessions/checking and symmetry/ordering were two of four symptom factors that were specifically associated with the occurrence of TLEs. These results are generally supportive of a pathoplastic relationship between TLEs and OCD symptomatology and thus suggest the need for greater systematic consideration of life stresses in research focused on the nature and treatment of OCD.

What is the optimal way to subdivide obsessive-compulsive disorder?

The clinical presentation of obsessive-compulsive disorder (OCD) varies not only across patients but over the course of the disorder. This diversity indicates that OCD is a heterogeneous disorder, which may have an important impact on psychopathological, longitudinal, genetic, and treatment research. To better understand OCD heterogeneity, more homogeneous phenotypic descriptions are necessary to delimiting clinically meaningful subgroups of patients. Besides phenotypic descriptions, another method of delimiting OCD patient subgroups includes the search for endophenotypes (extended phenotypes) based on neurophysiological, immunological, genetic, neuropsychological, or neuroanatomic (neuroimaging) paradigms. This article will describe some strategies that deal with OCD heterogeneity, including the identification of more homogeneous phenotypical categories, an improved understanding of obsessive-compulsive symptom dimensions and how to use them as quantitative traits, and broadening the diagnostic boundaries of OCD to include other related conditions. The relevance and limitations of each approach are also discussed. Since the etiological mechanisms associated with the expressions of OCD are unknown, there is probably not one but several heuristic strategies to search for more homogeneous OCD subgroup, that combined may provide the most fruitful results.

Antisocial personality disorder with childhood- vs. adolescence-onset conduct disorder: results from the National Epidemiologic Survey on Alcohol and Related Conditions

This study, based on a nationally representative, epidemiologic sample (N = 43,093, response rate 81%), compared sociodemographic and family history correlates, antisocial personality disorder (ASPD) symptom patterns, and Axis I and Axis II comorbidity, among adults with DSM-IV ASPD who reported onset of conduct disorder (CD) in childhood (<age 10) versus adolescence (> or =age 10). Prevalence of each ASPD diagnostic criterion and comorbid lifetime disorder was estimated. Logistic regression was used to examine associations of childhood-onset CD with ASPD symptom patterns and comorbid disorders. Among the 1422 respondents with ASPD, 447 reported childhood-onset CD. Childhood-onset respondents were more likely than adolescence-onset respondents to endorse CD criteria involving aggression against persons, animals, and property before age 15, and to endorse more childhood criteria and lifetime violent behaviors. Childhood-onset respondents displayed significantly elevated odds of lifetime social phobia, generalized anxiety disorder, drug dependence, and paranoid, schizoid, and avoidant personality disorders, but significantly decreased odds for lifetime tobacco dependence. Childhood-onset CD appears to identify a more polysymptomatic and violent form of ASPD, associated with greater lifetime comorbidity for selected Axis I and Axis II disorders, in nonclinical populations.

Sexual obsessions and clinical correlates in adults with obsessive-compulsive disorder

Because little is known about sexual obsessions in individuals with obsessive-compulsive disorder (OCD), we examined rates and clinical correlates of sexual obsessions in 293 consecutive subjects with primary lifetime Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, OCD (54.6% females; mean age, 40.5 +/- 12.9 years). Symptom severity was examined using the Yale-Brown Obsessive Compulsive Scale. Comorbidity, treatment response, insight, depression symptoms, quality of life, and social functioning were also assessed. All variables were compared in subjects who have OCD with and without sexual obsessions. Of the 293 subjects with primary OCD, 73 (24.9%) reported a history of sexual obsessions, and 39 (13.3%) of the subjects with OCD reported current sexual obsessions. Women were as likely as men to report sexual obsessions. As compared to those without these symptoms, subjects with current sexual obsessions were significantly more likely to report current aggressive (P < .001) and religious (P = .001) obsessions. Subjects with sexual obsessions also reported an earlier age of onset of OCD than subjects without these symptoms. Severity of OCD, comorbidity, treatment response, insight, depressive symptoms, quality of life, and social functioning did not differ between those with and without sexual obsessions. These preliminary results suggest that sexual obsessions are fairly common among individuals with OCD and may be associated with important clinical characteristics.

Anorexia nervosa with excessive exercise: a phenotype with close links to obsessive-compulsive disorder

Anorexia nervosa (AN) and obsessive-compulsive disorder (OCD) are highly comorbid, and appear to share a common neurophysiological dysfunction that contributes to the obsessional thoughts and compulsive behaviours seen in both disorders. Obsessive-compulsive personality (OCP) traits are also important risk factors for AN. Since excessive exercise has also been associated with greater obsessionality, we hypothesised that AN patients with a hyperactive behavioural profile represent a phenotype more closely linked to OCD than their non-exercising counterparts. We examined prospectively 50 female AN-Restrictor patients whom we classified as "excessive" or "non-excessive" based on their exercise status i) at admission and ii) over the lifetime of their illness. Validated measures of OCD symptoms and OCP traits were obtained at admission and after refeeding at discharge. On both classification methods, excessive exercisers had greater OCD symptoms and OCP traits than the non-excessive group, but did not differ on body mass index. OCD symptoms, but not OCP traits, decreased between admission and discharge. Findings support our prediction that AN patients with excessive physical activity constitute a subtype of the disorder with strong links to OCD. Indeed, this phenotype may be a culture-bound variant of OCD.

Factor analysis of obsessive-compulsive disorder YBOCS-SC symptoms and association with 5-HTTLPR SERT polymorphism

Symptoms defining obsessive-compulsive disorder (OCD) are diverse. Factor analyses of OCD symptoms have been used to evaluate obsessive-compulsive phenotypes that are thought to be more homogenous than the macro phenotype. There is evidence that three factors (symmetry/ordering, obsessions/checking, and hoarding) are familial and preliminary evidence that repetitive rituals are associated with a functional polymorphism in the promotor region of the serotonin transporter gene (5-HTTLPR). The goal of this study was to examine relationships between OCD symptom dimensions and 5-HTTLPR. We genotyped 153 subjects who met DSM-IV criteria for OCD. We used the Yale-Brown obsessive-compulsive scale symptom checklist (YBOCS-SC) to assess OCD symptoms. Using principle components analysis, we derived four factors from the 13 symptom categories of the YBOCS-SC in this patient sample, which replicated previous factor analyses of this scale. The frequencies of the S allele and the SS genotype were associated with the second factor including obsessions regarding symmetry and compulsions involving repeating, counting, and ordering/arranging. This study may contribute to understanding of molecular genetic features underlying the appearance of symptom clusters in OCD.

Common and distinct neural correlates of obsessive-compulsive and related disorders

Obsessive-compulsive disorder (OCD) often co-occurs with other anxiety disorders and a number of other disorders of similar phenomenology known as the "OCD spectrum" disorders. Neurobiologically, it is unclear how all these disorders relate to each other. The picture is further complicated by the clinical heterogeneity of OCD itself. This article reviews the literature on the common and distinct neural correlates of OCD, its symptom dimensions, and other anxiety and OCD spectrum disorders with the hope of providing a conceptual and heuristic framework to help understand the relationship between these phenomena.

Psychiatric comorbidities of female inpatients with eating disorders

OBJECTIVE

We analyze 27 point-prevalent DSM-IV Axis I comorbidities for eating disorder inpatients.

METHODS

The sample included 2436 female inpatients treated between January 1, 1995, and December 31, 2000, for primary DSM-IV diagnoses of anorexia, bulimia, and eating disorder not otherwise specified. Analyses were multivariate analysis of variance and multinomial logistic regression; sociodemographics and severity-of-illness measures were controlled.

RESULTS

Ninety-seven percent of patients evidenced > or = 1 comorbid diagnoses; 94% evidenced comorbid mood disorders, largely unipolar depression, with no differences across eating disorders; 56% evidenced anxiety disorders, with no differences across eating disorders; and 22% evidenced substance use disorders, with significant differences across eating disorders (p < .0001). Five specific diagnoses differed across eating disorders. Alcohol abuse/dependence was twice as likely with bulimia (p < .0001); polysubstance abuse/dependence three times as likely with bulimia (p < .0001); obsessive-compulsive disorder twice as likely with restricting and binge/purge anorexia (p < .01); posttraumatic stress disorder twice as likely with binge-purge anorexia (p < .05); schizophrenia/other psychoses three times more likely with restricting anorexia (p < .05) and two times with binge-purge anorexia (p < .05).

CONCLUSIONS

New findings emerged: extremely high comorbidity regardless of eating disorder, ubiquitous depression across all eating disorders, no difference in overall rate of anxiety disorders across eating disorders, greater posttraumatic stress disorder in binge-purge anorexia, more psychotic diagnoses in anorexia. Certain previous findings were confirmed: more obsessive-compulsive disorder in anorexia; more substance use in bulimia; and a replicated comorbidity rank-ordering for eating disorder patients: mood, anxiety, and substance use disorders, respectively.

The Dimensional Yale-Brown Obsessive-Compulsive Scale (DY-BOCS): an instrument for assessing obsessive-compulsive symptom dimensions

Obsessive-compulsive disorder (OCD) encompasses a broad range of symptoms representing multiple domains. This complex phenotype can be summarized using a few consistent and temporally stable symptom dimensions. The objective of this study was to assess the psychometric properties of the Dimensional Yale-Brown Obsessive-Compulsive Scale (DY-BOCS). This scale measures the presence and severity of obsessive-compulsive (OC) symptoms within six distinct dimensions that combine thematically related obsessions and compulsions. The DY-BOCS includes portions to be used as a self-report instrument and portions to be used by expert raters, including global ratings of OC symptom severity and overall impairment. We assessed 137 patients with a Diagnostic and Statistical Manual-IV diagnosis of OCD, aged 6-69 years, from sites in the USA, Canada and Brazil. Estimates of the reliability and validity of both the expert and self-report versions of the DY-BOCS were calculated and stratified according to age (pediatric vs. adult subjects). The internal consistency of each of the six symptom dimensions and the global severity score were excellent. The inter-rater agreement was also excellent for all component scores. Self-report and expert ratings were highly intercorrelated. The global DY-BOCS score was highly correlated with the total Yale-Brown Obsessive-Compulsive Scale score (Pearson r = 0.82, P<0.0001). Severity scores for individual symptom dimensions were largely independent of one another, only modestly correlated with the global ratings, and were also differentially related to ratings of depression, anxiety and tic severity. No major differences were observed when the results were stratified by age. These results indicate that the DY-BOCS is a reliable and valid instrument for assessing multiple aspects of OCD symptom severity in natural history, neuroimaging, treatment response and genetic studies when administered by expert clinicians or their highly trained staff.

Deconstructing obsessive-compulsive disorder: a multidimensional perspective

PURPOSE OF REVIEW

The aim of this article is to critically summarize the most promising attempts to split obsessive-compulsive disorder into subgroups based on clinical characteristics (i.e. age of onset, presence of comorbid tics, positive family history) and symptom theme, with particular emphasis on the latter.

RECENT FINDINGS

Attempts to split obsessive-compulsive disorder into mutually exclusive sub-groups based on clinical characteristics have been useful but not exempt of problems. The complex clinical presentation of the condition can be reduced to a few consistent, temporally stable symptom dimensions that can coexist in any given individual. Researchers have begun to investigate the genetics and neural mechanisms of these symptom dimensions and to develop specific assessment and treatment protocols for each particular problem.

SUMMARY

The multidimensional model of obsessive-compulsive disorder proposes a middle ground between the 'lumping' and 'splitting' perspectives. The disorder can be better understood as a spectrum of multiple potentially overlapping syndromes. The most fruitful research strategy will be to examine the common and specific etiological factors implicated in each symptom dimension.