Obsessive-compulsive disorder subtypes: an attempted replication and extension of a symptom-based taxonomy

A symptom-based subgroup taxonomy for obsessive-compulsive disorder (OCD) was evaluated and refined. The Yale-Brown Obsessive-Compulsive Scale symptom checklist was scored and cluster analysis was conducted with a sample of OCD patients (N = 114). Results were compared to Calamari et al.'s (Behaviour Research and Therapy 37 (1999) 113) five subgroup model. Rules for determining the number of subgroups supported a more complex model. In between sample comparisons, a stable contamination subgroup was found in both a five and seven subgroup taxonomy. Between sample stability was not as strong for Harming, Obsessionals, Symmetry, and Certainty subgroups. Hoarding, as a distinctive subgroup, was unstable in separate samples. When the Calamari et al. sample and the present sample were combined (N = 220), we found a reliable Hoarding subgroup. More interpretable and stable models emerged with the combined samples suggesting that large clinical samples are needed to identify OCD subgroups. Greater support was found for a seven subgroup taxonomy based subgroup interpretability and validation measure differences. The potential utility of symptom-based subgroup models of OCD and alternative approaches are discussed. Identification of reliable and valid OCD subtypes may advance theory and treatment.     

Attributional style in psychosis--the role of affect and belief type

People holding persecutory beliefs have been hypothesised to show a self-serving attributional style, which functions to protect self-esteem Bentall, Corcoran, Howard, Blackwood, and Kinderman (2001). Experimental support for this has been mixed. Freeman et al. (1998) suggested depressed and grandiose subgroups of those with persecutory beliefs might explain events differently. In this study, 71 participants completed measures of delusional beliefs, depression and attributional style. We hypothesised that those with persecutory beliefs would form grandiose and depressed subgroups, and that a self-serving attributional style would characterise only the grandiose subgroup. Hypotheses were partially confirmed. Clear subgroups were evident and only those with both persecutory and grandiose beliefs showed an externalising attributional style for negative events. Depression, irrespective of co-occurring persecutory beliefs, was related to a reduced self-serving bias and an externalising attributional style for positive events. On their own, persecutory beliefs were not related to any particular attributional style. Depressed and grandiose subgroups of those with persecutory beliefs might account for some of the inconsistencies in the attribution literature. Even within a single symptom group, care should be taken in both research and therapy to consider individual symptom patterns.     

Anxiety sensitivity and obsessive--compulsive disorder

Anxiety sensitivity (AS), a cognitive risk factor for anxiety disorders, was evaluated in a homogeneous obsessive-compulsive disorder (OCD) sample. A total of 280 individuals with OCD completed measures. Evaluation of the Anxiety Sensitivity Index revealed a latent structure that was congruent with previous studies showing a single higher order and three lower order factors, although greater variance was accounted for by the general factor than in a previous study. AS was significantly associated with OCD symptom severity after controlling for other putative cognitive risk factors, although the additional variance explained was small. Variability in the relationship of AS to OCD symptom severity was found across OCD symptom subgroups. Results suggest that AS might be an important aspect of OCD-relevant cognition for specific OCD subgroups, and the need for experimental evaluation is discussed.     

Implicit learning, thought-focused attention and obsessive-compulsive disorder: a replication and extension

Although significant empirical support exists for both cognitive and neurobiological models of obsessive-compulsive disorder (OCD), there have been few efforts to integrate findings. In this investigation, we attempted to link models by examining relationships between performance on information processing tasks posited to be markers of OCD-related neuropathology and a self-report measure of excessive thought-focused attention (cognitive self-consciousness; CSC). Congruent with predictions and prior research, OCD patients' performance was impaired in comparison to an anxious control group on the Serial Reaction Time (SRT) Task, a measure of implicit procedural learning. Following completion of the SRT, participants' awareness of the embedded stimulus pattern was assessed. As predicted, participants with OCD demonstrated superior performance on this task. Scoring on a measure of CSC correlated with performance on both tasks, although the amount of variance accounted for was modest. Evaluation of OCD symptom subgroups revealed greater procedural learning impairment in a hoarding subgroup. Implications for theory and treatment are discussed.     

The relationship between obsessive beliefs and symptom dimensions in obsessive-compulsive disorder

Research findings on the specific relationships between beliefs and OCD symptoms have been inconsistent, yet the existing studies vary in their approach to measuring the highly heterogeneous symptoms of this disorder. The Dimensional Obsessive-Compulsive Scale (DOCS) is a new measure that allows for the assessment of OCD symptom dimensions, rather than types of obsessions and compulsions per se. The present study examined the relationship between OCD symptom dimensions and dysfunctional (obsessive) beliefs believed to underlie these symptom dimensions using a large clinical sample of treatment-seeking adults with OCD. Results revealed that certain obsessive beliefs predicted certain OCD symptom dimensions in a manner consistent with cognitive-behavioral conceptual models. Specifically, contamination symptoms were predicted by responsibility/threat estimation beliefs, symmetry symptoms were predicted by perfectionism/certainty beliefs, unacceptable thoughts were predicted by importance/control of thoughts beliefs and symptoms related to being responsible for harm were predicted by responsibility/threat estimation beliefs. Implications for cognitive conceptualizations of OCD symptom dimensions are discussed.     

Do obsessional beliefs discriminate OCD without tic patients from OCD with tic and Tourette's syndrome patients?

There is considerable overlap in symptomatology between Tourette's syndrome (TS) and obsessive-compulsive disorder (OCD). Increased rates of tics are found in OCD and up to 60% obsessive-compulsive symptoms in TS. However, in OCD obsessive-compulsive symptoms are more often anxiety-related and, as a consequence, aimed at anxiety-reduction, whereas in TS these symptoms are more stimulus-bound. Therefore, it is of clinical interest to study whether these phenomenological differences are reflected in differences between dysfunctional cognitions accompanying OC symptoms in OCD with or without tics and TS. Current cognitive theory of OCD ascertains that specific dysfunctional beliefs are important in the etiology and maintenance of OCD. To assess these beliefs, the obsessive-compulsive beliefs questionnaire-87 (OBQ-87) has been developed. In the present study, OBQ-87 scores of OCD patients without tics, OCD with tics, and TS (without OCD) patients were compared to those of normal controls. Results: OCD without tic patients exhibited higher OBQ-87 scores than TS patients. No differences were found between OCD with or without tic patients on any of the OBQ-87 subscales. These results suggest that: (1) dysfunctional beliefs have no discriminative power with respect to OCD with or without tic patients; (2) the direct relationship between types of OC symptoms and specific dysfunctional beliefs is questionable. Therefore, one can doubt the specificity of cognitive theory of OCD to explain specific OC behavior.     

The role of cognitive factors in the pathogenesis of obsessive-compulsive symptoms: a prospective study

Cognitive models of obsessive-compulsive disorder (OCD) posit that specific kinds of dysfunctional beliefs (e.g., pertaining to responsibility and the significance of intrusive thoughts) underlie the development of this disorder. The present study was designed to prospectively evaluate whether dysfunctional beliefs thought to underlie OCD act as a specific vulnerability factor in the pathogenesis of obsessive-compulsive symptomatology. Eighty-five individuals were prospectively followed over a period of time thought to be associated with an increased onset of OCD symptoms -- childbirth and the postpartum. The majority of these new mothers and fathers experienced intrusive infant-related thoughts and performed neutralizing behaviors similar to, but less severe than, those observed in OCD. Scores on a measure of dysfunctional beliefs thought to underlie OCD predicted the development of obsessive-compulsive symptoms after controlling for pre-existing OCD symptoms, anxiety, and depression. Dysfunctional beliefs also predicted the severity of checking, washing, and obsessional OCD symptom dimensions, but not neutralizing, ordering, or hoarding symptom dimensions. These data provide evidence for specific dysfunctional beliefs as risk factors in the development of some types of OCD symptoms.     

Diagnostic Discrimination of Patients with Different OCD Main Symptom Domains from each Other and from Anxious and Depressive Controls

The extent to which the subscales of multidimensional OCD measures accurately distinguish patients with specific OCD main symptom domains from controls at different cutscores has not yet been examined. Diagnostic accuracy of OCD measures usually is determined by comparing the total scores of heterogeneous OCD samples and controls and therefore may underestimate the measures’ discrimination potential. In the current study, subtype-specific diagnostic accuracy and criterion-related validity of the Obsessive-Compulsive Inventory-Revised (OCI-R) subscales were examined in 327 patients with OCD, anxiety, and/or depressive disorders. All subscales demonstrated good to excellent criterion-related validity and diagnostic accuracy for distinguishing patients with specific OCD main symptom domains from controls. As expected, the single OCI-R subscales lead to more accurate diagnostic decisions than the total scale. Thus, the subscale-specific cutscores significantly improve the OCI-R’s utility for subtype-specific treatment planning and outcome measurement. Furthermore, an alternative classification algorithm distinguishing patients with OCD from controls based on subscale cutscores leads to a better sensitivity, but also to a lower specificity than discrimination based on the total scale cutscore.     

Cognitive Mediation of Symptom Change in Exposure and Response Prevention for Obsessive-Compulsive Disorder

This study examined cognitive mediators of symptom change during exposure and response prevention (EX/RP) for obsessive–compulsive disorder (OCD). Based on cognitive models of OCD, obsessive beliefs were hypothesized as a mediator of symptom change. Participants were 70 patients with primary OCD receiving EX/RP either as part of a randomized controlled trial (n = 38) or in open treatment following nonresponse to risperidone or placebo in the same trial (n = 32). Blinded evaluations of OCD severity and self-report assessments of three domains of obsessive beliefs (i.e., responsibility/threat of harm, importance/control of thoughts, and perfectionism/intolerance of uncertainty) were administered during acute (Weeks 0, 4 and 8) and maintenance treatment (Weeks 12 and 24). Study hypotheses were examined using cross-lagged multilevel modeling. Contrary to predictions, the obsessive beliefs domains investigated did not mediate subsequent OCD symptom reduction. In addition, OCD symptoms did not significantly mediate subsequent change in obsessive beliefs. The present study did not find evidence of cognitive mediation during EX/RP for OCD, highlighting the need to investigate other plausible mediators of symptom improvement.     

Does subgroup membership information lead to better estimation of true subscores?

Haberman (2008) suggested a method to determine if subtest scores have added value over the total score. The method is based on classical test theory and considers the estimation of the true subscores. Performance of subgroups, for example, those based on gender or ethnicity, on subtests is often of interest. Researchers such as Stricker (1993) and Livingston and Rupp (2004) found that the difference in performance between the subgroups often varies over the different subtests. We suggest a method to examine whether the knowledge of the subgroup membership of the examinees leads to a better estimation of the true subscores. We apply our suggested method to data from two operational testing programmes. The knowledge of the subgroup membership of the examinees does not lead to a better estimation of the true subscore for the data sets.     

The PANDAS subgroup: recognition and treatment

A subgroup of patients with childhood-onset obsessive-compulsive disorder (OCD) has been identified who share a common clinical course characterized by dramatic symptom exacerbations following Group A beta-hemolytic streptococcal (GABHS) infections. The term PANDAS has been applied to the subgroup, to indicate the postulated etiology of their symptoms: Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections. Five clinical characteristics define the PANDAS subgroup: presence of OCD and/or tic disorder, prepubertal symptom onset, sudden onset or abrupt exacerbations (sawtooth course), association with neurological abnormalities (presence of adventitious movements or motoric hyperactivity during exacerbations), and temporal association between symptom exacerbations and GABHS infections. Post-streptococcal symptom exacerbations are typically quite dramatic, with patients reporting that their symptoms "...came on overnight" or "...appeared all of a sudden a few days after I had a sore throat." The post-streptococcal inflammatory nature of the neuropsychiatric symptoms provides novel opportunities for treatment and prevention, including immunomodulatory therapies such as therapeutic plasma exchange (TPE) and intravenous immunoglobulin (IVIG). A recently completed placebo-controlled trial revealed that both IVIG and TPE were effective in reducing neuropsychiatric symptom severity (40% to 55% reductions, respectively) for a group of severely ill children with OCD and/or tic disorders. Further research is required to determine why the treatments are helpful, as well as to ascertain whether or not antibiotic prophylaxis can help prevent post-streptococcal symptom exacerbations.     

Do patients with OCD and pathological gambling have similar dysfunctional cognitions?

The obsessive-compulsive spectrum disorder (OCSD) theory postulates that a wide range of disorders is closely related to OCD. Current cognitive models ascertain that certain beliefs leading to misinterpretation of the significance of intrusions are important in the etiology and maintenance of OCD. This study examined whether pathological gambling, a disorder belonging to the OC spectrum, is characterized by similar dysfunctional cognitions as OCD. Dysfunctional beliefs of OCD patients were compared to those of patients with pathological gambling, panic disorder and normal controls. These beliefs were measured by the Obsessive-compulsive Beliefs Questionnaire-87 (OBQ-87), which was developed by a group of leading OCD researchers [Behav. Res. Ther. 35 (1997) 667]. It was hypothesized that according to the OCSD theory, pathological gamblers would exhibit similar cognitions to OCD patients, as well as increased levels of OCD symptoms. Analysis showed that OCD patients exhibited higher OBQ-87 scores than both panic patients and normal controls, but equal to pathological gambling patients. Pathological gamblers exhibited, however, no increase in OCD symptoms. These mixed results do not seem to support the OC spectrum theory for pathological gambling, moreover being contradictory to contemporary cognitive OCD models.     

Implicit and explicit appraisals of the importance of intrusive thoughts

To evaluate cognitive theories of obsessions, the current study experimentally manipulated appraisals of the importance of intrusive thoughts. Undergraduate students (N = 156) completed measures of obsessive-compulsive disorder (OCD) symptoms and beliefs and were primed with a list of commonly reported unwanted thoughts. Participants were then informed that unwanted thoughts are either (1) significant and indicative of their personal values, or (2) meaningless, or participants (3) received no instructions about unwanted thoughts. Participants then completed implicit and explicit measures of self-evaluation and interpretations of their unwanted thoughts. Results indicated that the manipulation shifted implicit appraisals of unwanted thoughts in the expected direction, but not self-evaluations of morality or dangerousness. Interestingly, explicit self-esteem and beliefs about the significance of unwanted thoughts were associated with measures of OCD beliefs, whereas implicit self-evaluations of dangerousness were better predicted by the interaction of pre-existing OCD beliefs with the manipulation. Results are discussed in terms of divergent predictors of implicit and explicit responses to unwanted thoughts.     

Relationships between anger, symptoms, and cognitive factors in OCD checkers

The purpose of this study was to examine whether individuals diagnosed with obsessive-compulsive disorder (OCD) with primary checking compulsions report higher levels of trait anger and anger expression compared with a student control group, and whether trait anger and anger expression are correlated with specific beliefs and interpretations that are common among individuals who compulsively check. A group of individuals with OCD reporting significant checking compulsions (n=33) and a group of undergraduate students (n=143) completed a questionnaire package that included measures of trait anger and anger expression, as well as measures of obsessive-compulsive symptoms and beliefs. The compulsive checking group reported greater trait anger, though not greater anger expression, than the student control group. Furthermore, beliefs concerning perfectionism and intolerance of uncertainty were positively correlated with anger expression and trait anger among compulsive checkers but not among the student control group. The implications of these findings are discussed in terms of cognitive-behavioural treatments for and models of compulsive checking in OCD.     

Responsibility attitudes and interpretations are characteristic of obsessive compulsive disorder

The cognitive-behavioural theory of Obsessive Compulsive Disorder (OCD) proposes that a key factor influencing obsessional behaviour is the way in which the intrusive cognitions are interpreted. The present paper reports an investigation of links between clinical symptoms (of anxiety, depression and obsessionality) and responsibility beliefs. These beliefs include not only measures of general responsibility attitudes (assumptions) but also more specific responsibility appraisals consequent on intrusive cognitions. The characteristics of two new questionnaires specifically designed to measure these beliefs were assessed in patients suffering from Obsessive Compulsive Disorder, in patients suffering from other anxiety disorders and in non-clinical controls. The scales measuring negative beliefs about responsibility were found to have good reliability and internal consistency. Comparisons between criterion groups indicate considerable specificity for both assumptions and appraisals with respect to OCD. There was also good evidence of specificity in the association between responsibility cognitions and obsessional symptoms across groups, and that this association was not a consequence of links with anxiety or depressive symptoms. Although the two measures were correlated, they each made unique contributions to the prediction of obsessional symptoms. Overall, the results are consistent with the hypothesis that responsibility beliefs are important in the experience of obsessional problems.     

Body dissatisfaction and irrational beliefs

To test the hypothesis that the irrational evaluative beliefs, postulated by Rational-Emotive Behavior Therapy, are associated with body dissatisfaction, 94 women (21 diagnosed with an eating disorder, 38 with high body dissatisfaction but without an eating disorder, and 35 with low body dissatisfaction) completed the Survey of Personal Beliefs and the Eating Disorders Inventory. Analysis showed no significant difference in body dissatisfaction between the Eating Disordered and High Body Dissatisfaction subgroups. No significant correlations between body dissatisfaction and irrational beliefs were found for the Eating Disordered subgroup. For the High Body Dissatisfaction subgroup, significant but low correlations were found between scores on body dissatisfaction and irrational standards for self and others and with negative self-rating. In terms of irrational beliefs the Eating Disordered and High Body Dissatisfaction subgroups showed a significantly greater tendency towards Catastrophizing, Low Frustration Tolerance, and Negative self-rating, compared to the controls, without any significant difference between the former two groups. The Eating Disordered subgroup but not the High Body Dissatisfaction subgroup differed significantly from the controls in terms of more Self-directed demands.     

Cognitive Beliefs Across the Symptom Dimensions of Pediatric Obsessive-Compulsive Disorder: Type of Symptom Matters

The cognitive model of obsessive-compulsive disorder (OCD) posits that dysfunctional cognitive beliefs are crucial to the onset and maintenance of OCD; however, the relationship between these cognitive beliefs and the heterogeneity of OCD symptoms in children and adolescents remains unknown. We examined how the major belief domains of the cognitive model (inflated responsibility/threat estimation, perfectionism/intolerance of uncertainty, importance/control of thoughts) and dysfunctional metacognitions were related to OCD symptoms across the following dimensions: doubting/checking, obsessing, hoarding, washing, ordering, and neutralization. Self-report ratings from 137 treatment-seeking youth with OCD were analyzed. When cognitive beliefs and symptom dimensions were analyzed in tandem, inflated responsibility/threat estimation and dysfunctional metacognitions were uniquely related to doubting/checking, obsessing, and hoarding and perfectionism/intolerance of uncertainty to ordering. Cognitive beliefs explained a large proportion of variation in doubting/checking (61%) and obsessing (46%), but much less so in ordering (15%), hoarding (14%), neutralization (8%), and washing (3%). Similar relations between cognitive beliefs and symptom dimensions were present in children and adolescents. Cognitive beliefs appear to be relevant for pediatric OCD related to harm, responsibility, and checking, but they do not map clearly onto contamination and symmetry-related symptoms. Implications for OCD etiology and treatment are discussed.     

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.     

The status of hoarding as a symptom of obsessive-compulsive disorder

Hoarding is considered by many to be a symptom of obsessive-compulsive disorder (OCD). Yet although it is observed in people with OCD, hoarding symptoms also appear in a number of other psychological and psychiatric conditions. The present studies were conducted using samples of OCD patients, patients with other anxiety disorders, and a non-clinical sample to further elucidate the relationship between hoarding and OCD. Across two investigations, we found that (a) whereas OCD patients had higher scores than the other groups on non-hoarding symptoms, this was not the case for hoarding symptoms; (b) hoarding tended to correlate more weakly with other OCD symptoms (e.g., washing, checking) than these other symptoms intercorrelated; (c) items measuring hoarding had the weakest factor loadings when a measure of OCD symptoms was submitted to factor analysis; (d) hoarding symptoms were not correlated with global OCD or anxiety severity, whereas other OCD symptoms were; and (e) hoarding did not show consistent relationships with OCD-related cognitive variables. These results do not support a specific relationship between hoarding and OCD; and they call into question hoarding's status as a specific symptom of OCD. Results are also discussed in terms of the importance of functional assessment of hoarding and OCD symptoms.