Pauls DL, Fernandez TV, Mathews CA
… +2 more, State MW, Scharf JM
J Obsessive Compuls Relat Disord
· 2014 Oct · PMID 25506544
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Georges Gilles de la Tourette, in describing the syndrome that now bears his name, observed that the condition aggregated within families. Over the last three decades, numerous studies have confirmed this observation, an...Georges Gilles de la Tourette, in describing the syndrome that now bears his name, observed that the condition aggregated within families. Over the last three decades, numerous studies have confirmed this observation, and demonstrated that familial clustering is due in part to genetic factors. Recent studies are beginning to provide clues about the underlying genetic mechanisms important for the manifestation of some cases of Tourette Disorder (TD). Evidence has come from different study designs, such as nuclear families, twins, multigenerational families, and case-control samples, together examining the broad spectrum of genetic variation including cytogenetic abnormalities, copy number variants, genome-wide association of common variants, and sequencing studies targeting rare and/or variation. Each of these classes of genetic variation holds promise for identifying the causative genes and biological pathways contributing to this paradigmatic neuropsychiatric disorder.
Athey AJ, Elias JA, Crosby JM
… +4 more, Jenike MA, Pope HG, Hudson JI, Brennan BP
J Obsessive Compuls Relat Disord
· 2015 Jan · PMID 25485229
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OBJECTIVES: Disgust is a well-established phenomenon with known neurobiological correlates. However, it remains unclear how or whether disgust changes with clinical treatment, because few longitudinal studies have tracke...OBJECTIVES: Disgust is a well-established phenomenon with known neurobiological correlates. However, it remains unclear how or whether disgust changes with clinical treatment, because few longitudinal studies have tracked the association of disgust vulnerability and clinical symptoms in patient populations. METHODS: We assessed disgust propensity and symptoms of obsessive-compulsive disorder (OCD) in 134 patients receiving intensive residential treatment for OCD. Using linear regression with adjustment for age, sex, and depression severity, we tested the association between change in disgust propensity and change in OCD symptoms from admission to discharge. RESULTS: Change in disgust propensity was significantly associated with improvement in contamination/washing symptoms (β = 0.25 [95% confidence interval: 0.11-0.39]; = .001). No significant association was found between change in disgust propensity and change in other OCD symptom dimensions. CONCLUSIONS: In patients with OCD undergoing intensive residential treatment, disgust propensity appears to improve in parallel with contamination/washing symptoms.
J Obsessive Compuls Relat Disord
· 2014 Oct · PMID 25436183
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BACKGROUND: Prevalence is a simple statement about the frequency of a disease in the population. For many medical conditions, including Tourette syndrome, there are true cases that have not been previously diagnosed due...BACKGROUND: Prevalence is a simple statement about the frequency of a disease in the population. For many medical conditions, including Tourette syndrome, there are true cases that have not been previously diagnosed due to problems of access to appropriate clinical services. Therefore, to obtain a trustworthy estimate of prevalence, it is necessary to go beyond cases identified in clinical settings and evaluate community samples. METHOD: We reviewed 11 community surveys in children with Tourette syndrome (TS) published since 2000. We also examined the frequency of co-occurring psychiatric conditions in community samples and large clinically-ascertained samples. RESULTS: Transient tics are relatively common affecting as many as 20% of school-age children. The 11 studies reviewed here offer a wide range of estimates from 2.6 to 38 per 1000 children for TS. Six studies provide estimates in a narrower range from 4.3 to 7.6 per 1000, but the confidence interval around this narrower range remains wide. Six studies provided results on chronic tic disorders ranging from 3 to 50 per 1000 for Chronic Motor Tic Disorder and 2.5 to 9.4 per 1000 for Chronic Vocal Tic Disorder. Community samples and large clinically-ascertained samples consistently show high rates of ADHD, disruptive behavior and anxiety disorders in children with TS. CONCLUSIONS: The wide range of prevalence estimates for TS and chronic tic disorders is likely due to differences in sample size and assessment methods. The best estimate of prevalence for TS in school-age children is likely to fall between 4 and 8 cases per 1000. Clinical assessment of children with chronic tic disorders warrants examination of other problems such as ADHD, disruptive behavior and anxiety.
Black KJ, Jankovic J, Hershey T
… +3 more, McNaught KS, Mink JW, Walkup J
J Obsessive Compuls Relat Disord
· 2014 Oct · PMID 25436182
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Tourette syndrome (TS) is a heritable neuropsychiatric disorder commonly complicated by obsessions and compulsions, but defined by frequent unwanted movements (motor tics) and vocalizations (phonic tics) that develop in...Tourette syndrome (TS) is a heritable neuropsychiatric disorder commonly complicated by obsessions and compulsions, but defined by frequent unwanted movements (motor tics) and vocalizations (phonic tics) that develop in childhood or adolescence. In recent years, research on TS has progressed rapidly on several fronts. Inspired by the Fifth International Scientific Symposium on Tourette Syndrome, the articles in this special issue review advances in the phenomenology, epidemiology, genetics, pathophysiology, and treatment of TS.
J Obsessive Compuls Relat Disord
· 2014 Oct · PMID 25414812
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Tourette syndrome has been examined using many different neuroimaging techniques. There has been a recent surge of neuroimaging research papers related to Tourette syndrome that are exploring many different aspects of th...Tourette syndrome has been examined using many different neuroimaging techniques. There has been a recent surge of neuroimaging research papers related to Tourette syndrome that are exploring many different aspects of the disorder and its comorbidities. This brief review focuses on recent MRI-based imaging studies of pediatric Tourette syndrome, including anatomical, functional, resting state, and diffusion tensor MRI techniques. Consistencies across studies are explored, and particularly important issues involved in acquiring data from this special population are discussed.
J Obsessive Compuls Relat Disord
· 2014 Oct · PMID 25414811
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This study evaluated an adaptation of a Cognitive Bias Modification-Interpretation (CBM-I) procedure designed to shift interpretations of intrusive thoughts related to beliefs about the Importance and Control of Thoughts...This study evaluated an adaptation of a Cognitive Bias Modification-Interpretation (CBM-I) procedure designed to shift interpretations of intrusive thoughts related to beliefs about the Importance and Control of Thoughts (ICT). Individuals high in the ICT belief domain were randomly assigned to one of two conditions: (a) a positive (n = 38) condition in which scenarios about intrusive thoughts were repeatedly paired with benign interpretations; or (b) a control (n = 39) condition in which scenarios about intrusive thoughts were paired with 50% benign and 50% threatening interpretations. Further, participants engaged in an ICT stressor task. Structural equation modeling with bias-corrected bootstrapping was used to examine the effects of training on ICT-relevant interpretations, beliefs, and ICT stressor responding. As predicted, individuals in a positive (vs. control) training condition reported decreases in ICT-relevant interpretations and beliefs. Further, there was a small, statistically significant indirect (i.e., mediated) effect of training on measures of ICT stressor responding, which occurred via decreases in ICT-relevant beliefs. In sum, results indicate that training was effective in influencing interpretations and beliefs tied to Importance/Control of Thoughts and that there may be clinical utility to shifting this belief domain.
Falkenstein MJ, Rogers K, Malloy EJ
… +1 more, Haaga DA
J Obsessive Compuls Relat Disord
· 2014 Oct · PMID 25405081
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OBJECTIVE: This study sought to identify predictors of relapse in a behavior therapy trial for trichotillomania (TTM), or hair-pulling disorder. Relapse is common after treatment for TTM, and only a few studies have exam...OBJECTIVE: This study sought to identify predictors of relapse in a behavior therapy trial for trichotillomania (TTM), or hair-pulling disorder. Relapse is common after treatment for TTM, and only a few studies have examined what might predict relapse. METHOD: Data was examined from a TTM treatment study with a stepped-care approach (step 1. web-based self-help; step 2. individual behavior therapy) (N = 60). Implications of significant predictive relations were illustrated by constructing Probability of Treatment Benefit (PTB) charts (Lindhiem, Kolko, & Cheng, 2012), which quantify the probability of maintaining gains according to predictors of maintenance. RESULTS: Abstinence at the conclusion of treatment and lower TTM severity during initial response significantly predicted maintenance. Abstinence periods prior to treatment, residual urges after achieving abstinence, pre-treatment TTM severity, intrinsic motivation, and treatment compliance did not predict maintenance. CONCLUSIONS: Post-treatment abstinence and lower TTM severity during initial response predicted maintenance. Replications of this research are needed to determine the usefulness of these possible predictors in identifying relapse-prone patients, with the aim of improving clinical decision-making and developing strategies to help these patients better maintain gains. This is the first TTM study to use PTB charts, which can help clarify the meaning of prognostic analyses.
Samuels J, Grados MA, Riddle MA
… +19 more, Bienvenu OJ, Goes FS, Cullen B, Wang Y, Greenberg BD, Fyer AJ, McCracken JT, Geller D, Murphy DL, Knowles JA, Rasmussen SA, McLaughlin NC, Piacentini J, Pauls DL, Stewart SE, Shugart YY, Maher B, Pulver AE, Nestadt G
J Obsessive Compuls Relat Disord
· 2014 Oct · PMID 25309849
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Compared to studies in adults, there have been few studies of hoarding in children and adolescents with obsessive-compulsive disorder (OCD). In the current study, we evaluated OCD clinical features, Axis I disorders, and...Compared to studies in adults, there have been few studies of hoarding in children and adolescents with obsessive-compulsive disorder (OCD). In the current study, we evaluated OCD clinical features, Axis I disorders, and social reciprocity scores in 641 children and adolescents with OCD, of whom 163 (25%) had hoarding compulsions and 478 did not. We found that, as a group, youth with hoarding had an earlier age at onset and more severe lifetime OCD symptoms, poorer insight, more difficulty making decisions and completing tasks, and more overall impairment. The hoarding group also had a greater lifetime prevalence of panic disorder, specific phobia, Tourette disorder, and tics. As measured with the Social Reciprocity Scale, the hoarding group had more severe deficits in parent-rated domains of social communication, social motivation, and restricted interests and repetitive behavior. In a multivariable model, the overall social reciprocity score, age at onset of OCD symptoms, symmetry obsessions, and indecision were independently related to hoarding in these children and adolescents with OCD. These features should be considered as candidate risk factors for the development of hoarding behavior in pediatric OCD.
J Obsessive Compuls Relat Disord
· 2014 Oct · PMID 30245958
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Tourette syndrome (TS) is a neuropsychiatric condition associated with substantial distress and functional impairment. Pharmacotherapy has traditionally been considered the first-line intervention for this condition, but...Tourette syndrome (TS) is a neuropsychiatric condition associated with substantial distress and functional impairment. Pharmacotherapy has traditionally been considered the first-line intervention for this condition, but there is strong evidence that behavior therapy is a comparably effective treatment option. Here we review empirically supported behavior therapy protocols for treating TS and the evidence associated with each. Potential mechanisms through which behavior therapy operates and concerns surrounding the utilization of behavioral interventions are also discussed.
J Obsessive Compuls Relat Disord
· 2014 Oct · PMID 30197854
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BACKGROUND: Tourette syndrome (TS) is a neurodevelopmental disorder characterized by motor and vocal tics--rapid, repetitive, stereotyped movements or vocalizations lasting at least one year in duration. The goal of this...BACKGROUND: Tourette syndrome (TS) is a neurodevelopmental disorder characterized by motor and vocal tics--rapid, repetitive, stereotyped movements or vocalizations lasting at least one year in duration. The goal of this article was to review the long-term clinical course of tics and frequently co-occurring conditions in children with TS. METHODS: We conducted a traditional literature search to locate relevant articles regarding long-term outcome and prognosis in TS and tic disorders. RESULTS: Tics typically have an onset between the ages of 4 and 6 years and reach their worst-ever severity between the ages of 10 and 12 years. By age 10 years, most children are aware of nearly irresistible somatosensory urges that precede the tics. A momentary sense of relief typically follows the completion of a tic. Over the course of hours, tics occur in bouts, with a regular inter-tic interval. Tics increase during periods of psychosocial stress, emotional excitement and fatigue. Tics can become "complex" in nature and appear to be purposeful. Tics can be willfully suppressed for brief intervals and can be evoked by the mere mention of them. Tics typically diminish during periods of goal-directed behavior. Over the course of months, tics wax and wane. By early adulthood, roughly three-quarters of children with TS will have greatly diminished tic symptoms and more than one-third will be virtually tic free. CONCLUSION: Although tics are the defining aspect of TS, they are often not the most enduring or impairing symptoms in children with TS. Indeed in TS tics rarely occur in isolation, and other coexisting conditions--such as behavioral disinhibition, hypersensitivity to a broad range of sensory stimuli, problems with visual motor integration, procedural learning difficulties, attention-deficit hyperactivity disorder, obsessive-compulsive disorder, depression, anxiety, and emotional instability--are often a greater source of impairment than the tics themselves. Measures used to enhance self-esteem, such as encouraging independence, strong friendships and the exploration of interests, are crucial to ensuring positive adulthood outcome.
Pardue CM, Sibrava NJ, Boisseau CL
… +3 more, Mancebo MC, Eisen JL, Rasmussen SA
J Obsessive Compuls Relat Disord
· 2014 Jul · PMID 25068099
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The familial nature of OCD has been well established. Clinical characteristics such as early age of onset, comorbidity with tic disorders, and higher rates of symmetry symptoms have been associated with the familial aggr...The familial nature of OCD has been well established. Clinical characteristics such as early age of onset, comorbidity with tic disorders, and higher rates of symmetry symptoms have been associated with the familial aggregation of OCD, though little research has examined the differential impact of paternal and maternal OCD. The current study explored parental influence on the expression of these characteristics and reports on 310 probands diagnosed with OCD as well as 1,580 of their biological first-degree relatives. The probands were evaluated by trained clinical raters using semi-structured assessments, and relative diagnoses were obtained based on probands' reports. Similar to previous findings, 10.13% of the 1,580 relatives ( = 160) were reported to have significant OCD symptoms. Only probands who reported having a father with OCD, rather than any first-degree relative, were more likely to have an early age of onset, symmetry and exactness obsessions, and higher rates of comorbidity. No significant differences were found with respect to the probands who reported their mothers as having OCD. These findings suggest that paternal OCD, rather than simply any first-degree relative having OCD, may influence whether probands exhibit the clinical characteristics commonly associated with the familial subtype of OCD.
Few studies to date have studied the particular reasons endorsed by individuals with hoarding disorder (HD) for why they save or acquire certain objects. Understanding how reasons for saving and acquiring objects influen...Few studies to date have studied the particular reasons endorsed by individuals with hoarding disorder (HD) for why they save or acquire certain objects. Understanding how reasons for saving and acquiring objects influence hoarding severity and the degree to which the relationship depends on gender or age differences can have implications for the treatment of HD. The current study looked at reasons for saving and acquiring in 84 individuals diagnosed with HD. Consideration of the usefulness of an object as a reason for saving was the most consistently uniquely predictive of all of the reasons examined for saving and acquisition when controlling for gender differences and other endorsed reasons. These results may suggest that targeting specific reasons for saving and acquiring may be an efficient way to reduce hoarding severity, specifically related to ideas of utility and waste.
Calamari JE, Woodard JL, Armstrong KM
… +4 more, Molino A, Pontarelli NK, Socha J, Longley SL
J Obsessive Compuls Relat Disord
· 2014 Apr · PMID 24949284
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The lack of Obsessive-Compulsive disorder (OCD) symptom measures validated for use with older adults has hindered research and treatment development for the age group. We evaluated the Obsessive-Compulsive Inventory-Revi...The lack of Obsessive-Compulsive disorder (OCD) symptom measures validated for use with older adults has hindered research and treatment development for the age group. We evaluated the Obsessive-Compulsive Inventory-Revised (OCI-R; Foa et al., 2002) with participants aged 65 and older ( = 180) to determine if the measure was an effective tool for evaluating obsessional symptoms. Participants completed the OCI-R and a comprehensive assessment battery up to four times over approximately 18 months. Results supported the well-replicated latent structure of the OCI-R (i.e., Washing, Checking, Ordering, Obsessing, Hoarding, and Neutralizing.). OCI-R total score was robustly associated with OCD symptoms assessed 18 months later by clinical interview, while scores on self-report measures of worry, general anxiety, and depression were not. Results indicate the OCI-R is an effective OCD symptom measure for older adults, although replication with additional older adult samples is needed.
Frank H, Stewart E, Walther M
… +4 more, Benito K, Freeman J, Conelea C, Garci A
J Obsessive Compuls Relat Disord
· 2014 Jan · PMID 24860725
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Previous research has shown that among the various subtypes of obsessive-compulsive disorder (OCD), adults (e.g. Frost, Krause & Steketee, 1996) and older children and adolescents (Bloch et al., 2009; Storch et al., 2007...Previous research has shown that among the various subtypes of obsessive-compulsive disorder (OCD), adults (e.g. Frost, Krause & Steketee, 1996) and older children and adolescents (Bloch et al., 2009; Storch et al., 2007) with problematic hoarding have distinct features and a poor treatment prognosis. However, there is limited information on the phenomenology and prevalence of hoarding behaviors in young children. The present study characterizes children ages 10 and under who present with OCD and hoarding behaviors. Sixty-eight children received a structured interview-determined diagnosis of OCD. Clinician administered, parent-report, and child-report measures on demographic, symptomatic, and diagnostic variables were completed. Clinician ratings of hoarding symptoms and parent and child endorsement of the hoarding item on the CY-BOCS checklist (Scahill, Riddle, McSwiggin-Hardin, & Ort, 1997) determined inclusion in the hoarding group (=33). Compared to children without hoarding symptoms (=35), the presence of hoarding symptoms was associated with an earlier age of primary diagnosis onset and a higher proportion of ADHD and provisional anxiety diagnoses. These results are partially consistent with the adult literature and with findings in older children (Storch et al., 2007). Additional data on clinical presentation and phenomenology of hoarding are needed to form a developmentally appropriate definition of the behavior.
J Obsessive Compuls Relat Disord
· 2013 Oct · PMID 24855596
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Family accommodation (FA) in obsessive-compulsive disorder (OCD) refers to family members' or significant others' participation in or facilitation of patients' rituals and/or avoidance. With recent studies pointing to FA...Family accommodation (FA) in obsessive-compulsive disorder (OCD) refers to family members' or significant others' participation in or facilitation of patients' rituals and/or avoidance. With recent studies pointing to FA as a predictor of poorer treatment outcome, there is heightened interest in developing family-based interventions for OCD aimed at reducing FA. The interviewer-rated Family Accommodation Scale for OCD (FAS-IR) is the gold standard for assessing the types and severity of FA in OCD families. However, the cost of training interviewers and the time required for administration may limit its use in some settings. A valid self-rated version could be administered for research and clinical purposes with minimal burden and has the potential to be more widely used. The present study reports on the development and initial psychometric testing of the Family Accommodation Scale for OCD-Self Rated Version (FAS-SR). The FAS-SR was compared to the FAS-IR in a sample of 41 relatives of individuals with primary OCD, demonstrating excellent internal consistency, strong agreement with the FAS-IR, and expected convergence with criterion measures. Though further study using the self-rated version is needed, these findings suggest that the FAS-SR is a valid measure of FA and a time-saving, less costly alternative to the FAS-IR.
Lambert AE, Hu Y, Magee JC
… +2 more, Beadel JR, Teachman BA
J Obsessive Compuls Relat Disord
· 2014 Jan · PMID 24567889
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Some studies have found that trying to suppress thoughts increases their long-term recurrence, a phenomenon associated with psychopathology, particularly obsessive-compulsive disorder. However, effect sizes in thought su...Some studies have found that trying to suppress thoughts increases their long-term recurrence, a phenomenon associated with psychopathology, particularly obsessive-compulsive disorder. However, effect sizes in thought suppression studies have often been small and inconsistent. The present study sought to improve thought suppression conceptualization and measurement by examining two distinct dimensions of thought recurrence - frequency and duration of a thought's return - and how they evolve over time. After a thought focus period, 100 adults were assigned to either suppress or monitor the recurrence of an unpleasant thought for 4 min. Then, during a second four-minute period, participants were asked to monitor the thought's recurrence. Hierarchical linear modeling indicated that thought declined across time and the rate of decline slowed as time went on. Initially, the extent of thought remained short and stable for those asked to suppress, and increased linearly over time for those asked to monitor. Later, this pattern reversed. Duration increased linearly for those initially asked to suppress but was short and stable for those who initially monitored. Accounting for change over time and means of measuring recurrence (frequency vs. duration) may help elucidate past mixed findings, and improve thought suppression research methodology.
J Obsessive Compuls Relat Disord
· 2013 Jan · PMID 24073390
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We examined the predictive validity of explicit and implicit measures of threat overestimation in relation to contamination-fear outcomes using structural equation modeling. Undergraduate students high in contamination f...We examined the predictive validity of explicit and implicit measures of threat overestimation in relation to contamination-fear outcomes using structural equation modeling. Undergraduate students high in contamination fear ( = 56) completed explicit measures of contamination threat likelihood and severity, as well as looming vulnerability cognitions, in addition to an implicit measure of danger associations with potential contaminants. Participants also completed measures of contamination-fear symptoms, as well as subjective distress and avoidance during a behavioral avoidance task, and state looming vulnerability cognitions during an exposure task. The latent explicit (but not implicit) threat overestimation variable was a significant and unique predictor of contamination fear symptoms and self-reported affective and cognitive facets of contamination fear. On the contrary, the implicit (but not explicit) latent measure predicted behavioral avoidance (at the level of a trend). Results are discussed in terms of differential predictive validity of implicit versus explicit markers of threat processing and multiple fear response systems.
J Obsessive Compuls Relat Disord
· 2013 Jul · PMID 24058899
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Symmetry obsessions are a common symptom of obsessive-compulsive disorder (OCD) and have several demographic and clinical correlates. Appearance-related symmetry concerns appear common in body dysmorphic disorder (BDD);...Symmetry obsessions are a common symptom of obsessive-compulsive disorder (OCD) and have several demographic and clinical correlates. Appearance-related symmetry concerns appear common in body dysmorphic disorder (BDD); however, no published studies have examined this topic. This study examined the clinical features, prevalence, and correlates of symmetry concerns involving physical appearance in two BDD samples (=160 and =115). More than 25% of participants in each sample reported symmetry concerns for a body part with which they were preoccupied (total of 18 body parts in sample 1 and 18 in sample 2). In sample 1, BDD participants with appearance-related symmetry concerns were older than those without appearance-related symmetry concerns. In sample 2, those with appearance-related symmetry concerns reported poorer mental health-related quality of life, were more likely to have experienced lifetime suicidal ideation, had better BDD-related insight, and were less likely to have a lifetime eating disorder. In both samples, participants with appearance-related symmetry concerns were more likely to have lifetime OCD but OCD-related symmetry obsessions. Thus, symmetry is a common appearance concern in BDD that is associated with comorbid OCD but not with OCD symmetry concerns specifically, suggesting that symmetry concerns may have a different mechanism/pathophysiology in BDD versus OCD.
J Obsessive Compuls Relat Disord
· 2013 Apr · PMID 23888284
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We conducted a review to provide an update on the efficacy of psychological treatments for OCD in general and with regard to specific symptom presentations. The PubMed and PsycINFO databases were searched for randomized...We conducted a review to provide an update on the efficacy of psychological treatments for OCD in general and with regard to specific symptom presentations. The PubMed and PsycINFO databases were searched for randomized controlled trials (RCTs) published up to mid February 2012. Forty-five such studies were identified. Exposure and response prevention (ERP) and cognitive-behavioral therapy (CBT) were found to be efficacious and specific for OCD. More purely cognitive interventions that did not include ERP or behavioral experiments were found to be possibly efficacious, as were Acceptance and Commitment Therapy, Motivational Interviewing as an adjunct to the established treatments, Eye Movement Desensitization and Reprocessing, and Satiation Therapy. There was little support for Stress Management or Psychodynamic Therapy. Although the majority of the studies recruited mixed or unspecified samples of patients and did not test for moderation, CBT was efficacious for obsessional patients who lacked overt rituals. One more purely cognitive intervention named Danger Ideation Reduction Therapy was found to be possibly efficacious for patients with contamination obsessions and washing compulsions. Although ERP and CBT are the best established psychological treatments for OCD, further research is needed to help elucidate which treatments are most effective for different OCD presentations.
Meyer JF, Frost RO, Brown TA
… +2 more, Steketee G, Tolin DF
J Obsessive Compuls Relat Disord
· 2013 Jul · PMID 23814700
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Hoarding is a serious and potentially life-threatening mental health problem that, until recently, was considered a subtype of OCD. However, recent research suggests it is distinct and more prevalent than OCD. Three key...Hoarding is a serious and potentially life-threatening mental health problem that, until recently, was considered a subtype of OCD. However, recent research suggests it is distinct and more prevalent than OCD. Three key defining features have emerged in factor analytic studies of hoarding scales: excessive acquisition, difficulty discarding, and excessive clutter. Covariation among these defining features has received limited attention. The primary aim of the current study was to examine the role of the three key features in defining hoarding disorder. Convergent and discriminant validity of the three hoarding factors were examined in a multitrait-multimethod matrix. A secondary aim was to examine the extent to which each hoarding feature distinguished individuals meeting criteria for hoarding from those with OCD and community controls. Although the three-factor model provided an adequate fit for the data and convergent validities were high, the hoarding factors evidenced poor discriminant validity across measures. The findings provide preliminary support for a more parsimonious merging of the clutter, acquisition, and discarding subscales versus parsing out subscale scores. Specifically, the active acquisition of items, buildup of clutter, and difficulty discarding accumulated possessions co-occurred strongly enough to be considered a unidimensional construct. Thus, these symptoms were less attributable to separate phenomena and better conceived as part of a cohesive hoarding phenotype. Each of the three factors discriminated hoarding participants from OCD patients and community controls, but did not discriminate the latter two groups. The findings have implications for treating acquisition as a specifier in DSM-5.