Michael G. Wheaton

Assessment of Obsessive-Compulsive Symptom Dimensions: Development and Evaluation of the Dimensional Obsessive-Compulsive Scale

Although several measures of obsessive-compulsive (OC) symptoms exist, most are limited in that they are not consistent with the most recent empirical findings on the nature and dimensional structure of obsessions and compulsions. In the present research, the authors developed and evaluated a measure called the Dimensional Obsessive-Compulsive Scale (DOCS) to address limitations of existing OC symptom measures. The DOCS is a 20-item measure that assesses the four dimensions of OC symptoms most reliably replicated in previous structural research. Factorial validity of the DOCS was supported by exploratory and confirmatory factor analyses of 3 samples, including individuals with OC disorder, those with other anxiety disorders, and nonclinical individuals. Scores on the DOCS displayed good performance on indices of reliability and validity, as well as sensitivity to treatment and diagnostic sensitivity, and hold promise as a measure of OC symptoms in clinical and research settings.

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 hoardings status as a specific symptom of OCD. Results are also discussed in terms of the importance of functional assessment of hoarding and OCD symptoms.

A Haplotype Containing Quantitative Trait Loci for SLC1A1 Gene Expression and Its Association With Obsessive-Compulsive Disorder

CONTEXT Recent evidence from linkage analyses and follow-up candidate gene studies supports the involvement of SLC1A1, which encodes the neuronal glutamate transporter, in the development of obsessive-compulsive disorder (OCD). OBJECTIVES To determine the role of genetic variation of SLC1A1 in OCD in a large case-control study and to better understand how SLC1A1 variation affects functionality. DESIGN A case-control study. SETTING Publicly accessible SLC1A1 expression and genotype data. PATIENTS Three hundred twenty-five OCD probands and 662 ethnically and sex-matched controls. INTERVENTIONS Probands were assessed with the Structured Clinical Interview for DSM-IV, the Yale-Brown Obsessive Compulsive Scale, and the Saving Inventory-Revised. Six single-nucleotide polymorphisms (SNPs) were genotyped. Multiple testing corrections for single-marker and haplotype analyses were performed by permutation. RESULTS Gene expression of SLC1A1 is heritable in lymphoblastoid cell lines. We identified 3 SNPs in or near SLC1A1 that correlated with gene expression levels, 1 of which had previously been associated with OCD. Two of these SNPs also predicted expression levels in human brain tissue, and 1 SNP was further functional in reporter gene studies. Two haplotypes at 3 SNPs, rs3087879, rs301430, and rs7858819, were significantly associated with OCD after multiple-testing correction and contained 2 SNPs associated with expression levels. In addition, another SNP correlating with SLC1A1 gene expression, rs3933331, was associated with an OCD-hoarding subphenotype as assessed by 2 independent, validated scales. CONCLUSIONS Our case-control data corroborate previous smaller family-based studies that indicated that SLC1A1 is a susceptibility locus for OCD. The expression and genotype database-mining approach we used provides a potentially useful complementary approach to strengthen future candidate gene studies in neuropsychiatric and other disorders.

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.

Dimensions of anxiety sensitivity in the anxiety disorders: Evaluation of the ASI-3

Anxiety sensitivity (AS), the fear of sensations of anxious arousal based on beliefs about their harmful consequences, is increasingly recognized as a multidimensional construct. The recently developed Anxiety Sensitivity Index-3 [ASI-3; Taylor, S., Zvolensky, M., Cox, B., Deacon, B., Heimberg, R., Ledley, D. R., et al. (2007). Robust dimensions of anxiety sensitivity: Development and initial validation of the Anxiety Sensitivity Index-3 (ASI-3). Psychological Assessment, 19, 176-188] measures three dimensions of AS: physical concerns, social concerns, and cognitive concerns. The ASI-3 shows promise, although further evaluation of its psychometric properties and validity in independent samples is needed. We evaluated the ASI-3 in a mixed sample of anxiety disorder patients (N=506) and undergraduate student controls (N=315). The measure demonstrated a stable 3-factor structure and sound psychometric properties, with the three factors showing theoretically consistent patterns of associations with anxiety symptoms and diagnoses. ASI-3 total scores were less discriminative. Implications for conceptual models of anxiety are discussed.

Predicting anxiety: The role of experiential avoidance and anxiety sensitivity

Anxiety sensitivity (AS), the tendency to fear arousal-related body sensations based on beliefs that they are harmful, is a strong psychological risk factor for development of anxiety psychopathology; however, in most studies AS explains only a portion of the variability in anxiety symptoms. Recent theoretical and research work has suggested that experiential avoidance (EA), unwillingness to endure unpleasant internal experiences (e.g., thoughts, emotions, memories), is related to anxiety disorders. The current study examined independent contributions of EA and AS in the prediction of anxiety symptoms in a sample of 42 adults with DSM-IV anxiety disorders. Participants completed measures of AS, EA, anxiety, and depression. Correlational analyses indicated associations between AS, EA, and anxiety, yet more conservative regression analyses indicated that the Physical Concerns dimension of AS predicted anxiety symptom severity independently of EA. Theoretical and treatment implications of the results are discussed.

Enhancing Exposure and Response Prevention for OCD: A Couple-Based Approach

The effectiveness of individual therapy by exposure and response prevention (ERP) for obsessive–compulsive disorder (OCD) is well established, yet not all patients respond well, and some show relapse on discontinuation. This article begins by providing an overview of the personal and interpersonal experiences of OCD, focusing on interpersonal processes that maintain OCD symptoms and interfere with ERP. The study then describes a couple-based treatment program that the authors have developed to enhance ERP for individuals with OCD who are in long-term relationships. This program involves psychoeducation, partner-assisted exposure therapy, couple-based interventions aimed at changing maladaptive relationship patterns regarding OCD (i.e., symptom accommodation), and general couple therapy. Three case examples are presented to illustrate the couple-based techniques used in this treatment program.

Treating Obsessive-Compulsive Disorder in Intimate Relationships: A Pilot Study of Couple-Based Cognitive-Behavior Therapy

Although cognitive-behavioral therapy (CBT) involving exposure and response prevention (ERP) is an established treatment for obsessive-compulsive disorder (OCD), not all patients respond optimally, and some show relapse upon discontinuation. Research suggests that for OCD patients in close relationships, targeting relationship dynamics enhances the effects of CBT. In the present study, we developed and pilot tested a 16-session couple-based CBT program for patients with OCD and their romantic partners. This program included (a) partner-assisted ERP, (b) techniques targeting maladaptive relationship patterns focal to OCD (e.g., symptom accommodation), and (c) techniques targeting non OCD-related relationship stressors. OCD, related symptoms, and relationship functioning were assessed at baseline, immediately following treatment (posttest), and at 6- and 12-month follow-up. At posttest, substantial improvements in OCD symptoms, relationship functioning, and depression were observed. Improvements in OCD symptoms were maintained up to 1year. Results are compared to findings from studies of individual CBT for OCD and discussed in terms of the importance of addressing interpersonal processes that maintain OCD symptoms.

The relationship between religion and thought—action fusion: Use of an in vivo paradigm

Research has demonstrated that higher levels of religiosity are positively correlated with thought-action fusion (TAF), a set of cognitive biases found to be associated with obsessive-compulsive symptoms. However, previous studies have exclusively relied on a nomothetic approach to measuring TAF using a single self-report instrument, the thought-action fusion scale. The current study examined the relationship between religiosity and TAF using an in vivo behaviorally-based assessment in which participants thought about and wrote down thoughts of negative events involving loved ones. Forty-three highly religious Protestant Christians were compared to 30 Atheists/Agnostics on their in vivo ratings of anxiety, estimates of likelihood, and moral wrongness related to the negative thoughts. Results indicated that compared to the non-religious participants, those who were highly religious believed that writing and thinking about the negative events was more morally wrong and increased the likelihood of the event. Results are discussed in terms of the potential relationship between certain religious teachings and TAF-related beliefs about the importance, significance, and influence of thoughts.

The relationship between anxiety sensitivity and obsessive-compulsive symptom dimensions.

BACKGROUND AND OBJECTIVES Anxiety sensitivity (AS), the tendency to fear arousal-related body sensations based on beliefs that they are dangerous, is a cognitive vulnerability factor for certain anxiety symptoms such as panic and posttraumatic stress symptoms. Very little research, however, has examined the relationship between AS and obsessive-compulsive (OC) symptoms, which was the objective of the current research. METHODS We administered dimensional measures of AS and OC symptoms to a large sample of undergraduate students (N = 636). We also included measures of general distress and cognitive distortions related to OCD (i.e., obsessive beliefs) as control variables. RESULTS Regression analyses indicated that AS was predictive of OC symptoms even after controlling for general distress and obsessive beliefs. In addition, the three domains of AS (physical, social, and cognitive concerns) were differentially associated with the four dimensions of OC symptoms (contamination, responsibility for harm, symmetry, and unacceptable thoughts). LIMITATIONS Our findings are based on a non-clinical student sample and their generalization to OCD requires replication with a sample of OCD patients. CONCLUSIONS These results provide preliminary evidence that AS plays a role in OC symptoms. Implications for clinical practice and for future research are discussed.