Susanne Fricke

Symptom dimensions in obsessive–compulsive disorder: prediction of cognitive-behavior therapy outcome

Objective:  A significant number of patients with obsessive–compulsive disorder (OCD) fail to benefit sufficiently from treatments. This study aimed to evaluate whether certain OCD symptom dimensions were associated with cognitive‐behavioral therapy (CBT) outcome.

Impact of comorbid depressive symptoms on neuropsychological performance in obsessive-compulsive disorder.

There is indirect evidence from previous research that several executive disturbances in obsessive-compulsive disorder (OCD) are mediated by comorbid depressive symptoms. For the present study, the authors investigated whether OCD patients with elevated Hamilton Rating Scale for Depression (HRSD) scores would exhibit deficits in tasks sensitive to the medial and dorsolateral frontal cortex as well as other executive tasks. The 36 OCD patients were split along the median according to their HRSD scores and compared with matched control subjects. Patients with high HRSD scores performed significantly worse than control subjects and patients with low HRSD scores on the Wisconsin Card Sorting Test, the Trail-Making Test (TMT, Part B), and the TMT difference score. Moreover, patients with high HRSD scores exhibited deficits on a (creative) verbal fluency task. It is suggested that comorbid depressive symptoms may have artificially inflated some executive deficit scores in previous studies.

Dissociation as a Predictor of Cognitive Behavior Therapy Outcome in Patients with Obsessive-Compulsive Disorder

Background: Previous studies have found a strong association between dissociation and obsessive-compulsive disorder (OCD). The purpose of the present study was to evaluate whether dissociation is a predictor of cognitive behavior therapy (CBT) outcome in patients with OCD. Methods: Fifty-two patients with OCD were assessed using the Dissociative Experience Scale (DES), the Yale-Brown Obsessive-Compulsive Scale and the Beck Depression Inventory. CBT lasted on average 9.5 weeks and included exposure therapy. Results: Patients who dropped out due to noncompliance had higher baseline DES scores and depression scores compared to the 43 patients (83%) who completed the study. Significant OCD symptom reduction at posttreatment was observed in study completers with a large effect size (d = 1.7). More severe OCD symptoms at posttreatment were associated with higher DES scores at baseline, and treatment nonresponders had significantly higher baseline DES scores compared to responders. These associations with outcome were mainly due to the DES subfactor absorption-imaginative involvement. In regression analyses, higher absorption-imaginative involvement scores at baseline predicted poorer CBT outcome, even after controlling for depressive symptoms, comorbid axis I disorders and concomitant psychotropic drugs. Conclusions: Results from this preliminary study suggest that higher levels of dissociation (particularly absorption-imaginative involvement) in patients with OCD might predict poorer CBT outcome. If our results can be replicated, treatment outcome might be improved by additional interventions for those patients with OCD who indicate high levels of dissociation, for example by using interventions aimed at improving coping with emotionally stressful situations.

Dimensional structure of the Yale–Brown Obsessive-Compulsive Scale (Y-BOCS)

The Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) is a widely used instrument to assess obsessive-compulsive symptomatology. The present study provides evidence that the Y-BOCS is best represented by a three-dimensional model comprising severity of obsessions (factor 1), severity of compulsions (factor 2) and resistance to symptoms (factor 3). On the basis of exploratory factor analysis, this structure was found for both baseline (n = 109) and discharge ratings (n = 68) following a multimodal cognitive-behavioral intervention. The factor solution remained essentially unchanged when two optional items (items 1b and 6b) were dropped from analysis. The three-factor structure was replicated with confirmatory factor analysis and showed better fit than previously proposed single- and two-factor models. For future research, we propose a new Y-BOCS scoring algorithm that takes this factor structure into account. A further result was that resistance significantly declined in response to cognitive-behavioral intervention, whereas drug treatment alone did not seem to moderate this variable according to previous research conducted by Kim et al. [Psychiatry Research 51 (1994) 203-211].

Long–term course and outcome of obsessive–compulsive patientsafter cognitive–behavioral therapy in combination with eitherfluvoxamine or placebo

AbstractLongitudinal studies with very long follow–up periods of patients with obsessive–compulsive disorder (OCD) who have received adequate treatment are rare. In the current study, 30 of 37 inpatients (81%) with severe OCD were followed up 6–8 years after treatment with cognitive–behavioral therapy (CBT) in combination with either fluvoxamine or placebo in a randomized design. The significant improvements (with large effectsizes) in obsessive–compulsive symptoms from pre- to post–treatment (41% reduction on the Y–BOCS) remained stable at follow–up (45 %). Responder rates, defined as ≥35% reduction on the Y–BOCS, were 67% and 60%, respectively. Depressive symptoms decreased significantly not only from pre- to post–treatment but also during follow–up. Re–hospitalization, which occurred in 11 patients (37 %), was associated with more severe depressive symptoms at pre–treatment and living without a partner. Full symptom remission at follow–up, defined as both Y–BOCS total score ≤ 7 and no longer meeting diagnostic criteria for OCD, was achieved by 8 patients (27 %). Patients without full remission at follow–up had a significantly longer history of OCD, assessed at pretreatment, compared to remitted patients. The shortterm treatment outcome had no predictive value for the long–term course. Throughout the naturalistic follow–up, nearly all patients (29 patients) received additional psychotherapy and/or medication. This might indicate that such chronic OCD patients usually need additional therapeutic support after effective inpatient treatment to maintain their improvements over long periods.

Positive schizotypal symptoms predict treatment outcome in obsessive–compulsive disorder

Previous research has suggested that the presence of schizotypal personality disorder may represent a risk factor for treatment failure in obsessive-compulsive disorder (OCD). Relying on a dimensional approach, the present study investigated whether the predictive importance of schizotypal personality is shared by all of its features to the same extent or whether it is confined to a subset of symptoms. Fifty-three patients underwent multi-modal cognitive-behavioral therapy with or without adjunctive antidepressive medication. Therapy response was defined as a 35% decline of the Y-BOCS total score. At baseline assessment, patients were asked to fill out the schizotypal personality questionnaire, the perceptual aberration scale and the Beck depression inventory. Stepwise regression analysis and group comparisons conducted with the schizotypal and depression scales revealed that elevated scores in the positive schizotypal scales, especially perceptual aberrations, were highly predictive for treatment failure. Responders to treatment and non-responders did not significantly differ on other variables or on scores in two scales which measured response biases. The study provides evidence that positive schizotypal symptoms are antecendents for treatment failure in OCD. It needs to be evaluated whether these at-risk individuals benefit from additional intervention, such as the adminstration of low-dose atypical neuroleptics and specifically tailored behavorial intervention.

A Prospective Study of Alexithymia in Obsessive-Compulsive Patients Treated with Multimodal Cognitive-Behavioral Therapy

Background: Alexithymia as a predictor of treatment outcome in psychotherapy has often been discussed but rarely evaluated in prospective studies. The present study evaluated the absolute and relative stability of alexithymia in patients with obsessive-compulsive disorder (OCD), and the predictive value of alexithymia for the outcome of treatment. Methods: We conducted a prospective study with 42 inpatients receiving intensive, multimodal cognitive-behavioral therapy (CBT). Patients were assessed for alexithymia at pre- and post-treatment with the 20-item Toronto Alexithymia Scale (TAS-20), for obsessive-compulsive symptoms and depression with the Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) and the 21-item Hamilton Depression Rating Scale (HDRS). Results: OCD and comorbid depression showed a highly significant symptom-reduction from pre- to post-treatment while no absolute changes in the TAS-20 total scores and its factors 1 and 3 occurred. Only factor 2 scores decreased significantly, but with a smaller effect size than the effect sizes for the changes in Y-BOCS and HDRS. Alexithymia scores at pre-treatment correlated significantly with alexithymia scores at the end of treatment, indicating its relative stability. In the linear regression analyses, no variables were identified that predicted significantly the outcome of treatment. Conclusions: Our findings support the view that alexithymia is a stable personality trait rather than a state-dependent phenomenon in obsessive-compulsive patients. Alexithymia scores do not predict response to multimodal CBT in OCD. It might be an effect of CBT that patients could at least partly regain or newly learn the capability to describe their feelings.

Examination of emotional Stroop interference in obsessive-compulsive disorder

Previous research has produced conflicting findings on whether or not patients with subclinical or manifest obsessive-compulsive disorder (OCD) share an attentional bias for anxiety-related material. In the present study, 35 OCD patients were compared with 20 healthy controls on their performance in an emotional Stroop paradigm. Nine different stimulus conditions were compiled, including sets for depression-related and anxiety-related words as well as stimuli from two constructs with a potential relevance for the pathogenesis and maintenance of OCD symptomatology: responsibility and conscientiousness. Patients did not show enhanced interference for any of the conditions. Syndrome subtype and severity, avoidance and speed of information processing did not moderate results. The present study concurs with most prior research that OCD patients display no interference effect for general threat words. It deserves further consideration, that emotional interference effects in OCD as seen in other anxiety disorders occur when using idiosyncratic word material with a direct relation to the individuals primary concerns.

Evidence for an attentional bias for washing- and checking-relevant stimuli in obsessive–compulsive disorder

There is equivocal evidence whether or not patients with obsessive-compulsive disorder (OCD) share an attentional bias for concern-related material and if so, whether this reflects hypervigilance towards or problems to disengage from disorder-related material. In a recent study, we failed to detect an attentional bias in OCD patients using an emotional variant of the inhibition of return (IOR) paradigm containing OCD-relevant and neutral words. We reinvestigated the research question with a more stringent design that addressed potential moderators. A new IOR paradigm was set up using visual stimuli. Forty-two OCD patients and 31 healthy controls were presented with neutral (e.g., cup), anxiety-relevant (e.g., shark), checking-relevant (e.g., broken door), and washing-relevant (e.g., dirty toilet) cue pictures at one of two possible locations. Following a short or long interval sensitive to automatic versus controlled processes, a simple target stimulus appeared at either the cued or the uncued location. OCD patients responded significantly slower to targets that were preceded by an OCD-relevant cue. Results lend support to the claim that OCD patients share a processing abnormality for concern-related visual material.

Effects of behavioral therapy or pharmacotherapy on brain glucose metabolism in subjects with obsessive-compulsive disorder as assessed by brain FDG PET

This prospective study investigated the effect of pharmacotherapy (PT) and cognitive behavioral therapy (CBT) on cerebral glucose metabolism in adults with obsessive-compulsive disorder (OCD). Dynamic positron emission tomography (PET) of the brain with F-18-fluorodeoxyglucose (FDG) was performed before and after treatment in 16 subjects diagnosed for OCD for at least 2 years (PT: n=7). Pre-to-post-treatment change of scaled local metabolic rate of glucose (SLMRGlc) was assessed separately in therapy responders and non-responders. Correlation was tested between SLMRGlc change and change of OCD, depression, or anxiety symptoms. SLMRGlc increased in the right caudate after successful therapy. The increase tended to correlate with the improvement of OCD symptom severity. The finding of increased local caudate activity after successful therapy is in contrast to most previous studies. Possible explanations include effects of therapy on concomitant depression symptoms and/or the large proportion of early-onset OCD in the present sample.