Factor structure of the Dimensional Yale-Brown Obsessive-Compulsive Scale in a large sample of adults with obsessive-compulsive disorder

Objectives: Although the Dimensional Yale-Brown Obsessive-Compulsive Scale (DY-BOCS) is a widely used instrument for assessing different obsessive-compulsive symptom dimensions, its factor structure has never been studied in a Brazilian population. Thus, we aimed to assess the goodness-of-fit indexes and factor loadings of two higher-order models of the DY-BOCS using confirmatory factor analysis (CFA) in a large obsessive-compulsive disorder (OCD) sample. Methods: We tested two CFA models in a sample of 955 adults with OCD who had been assessed with the DY-BOCS in a cross-sectional multi-site study. The first model encompassed the symptom checklist (present or absent), whereas the second focused on items related to severity scores. Results: Both models presented adequate goodness-of-fit indexes. The comparative fit index, Tucker-Lewis index, and omega were > 0.9, while the root mean square error of approximation was ≤ 0.06 for both models. Factor loadings for each item of each dimension are presented and discussed. Conclusion: Higher-order factor models showed adequate goodness-of-fit indexes, indicating that they appropriately measured OCD dimensions in this Brazilian population.

Is it time to change the gold standard of obsessive-compulsive disorder severity assessment? Factor structure of the Yale-Brown Obsessive-Compulsive Scale.

OBJECTIVES: The Yale-Brown Obsessive-Compulsive Scale has been considered the gold standard scale to assess obsessive-compulsive disorder severity. Previous studies using exploratory factor analysis and confirmatory factor analysis with this scale showed mixed findings in terms of factor structure and fit of models. Therefore, we used confirmatory factor analysis to compare different Yale-Brown Obsessive-Compulsive Scale models in a large sample aiming to identify the best model fit. METHODS: We assessed adult obsessive-compulsive disorder patients (n = 955) using three measures: Yale-Brown Obsessive-Compulsive Scale severity ratings, the Dimensional Yale-Brown Obsessive-Compulsive Scale and the clinical global impression scale. We tested all factor structures reported by previous studies to investigate which model best fitted the data: one-factor, two-factor, three-factor and their equivalent high-order solutions. We also investigated Yale-Brown Obsessive-Compulsive Scale items correlations with scores from the other measures of obsessive-compulsive disorder severity. RESULTS: Confirmatory factor analysis models presented mediocre to fair goodness-of-fit indexes. Severity items related to resistance to obsessions and compulsions presented low factor loadings. The model with the best fit indexes was a high-order model without obsessive-compulsive disorder resistance items. These items also presented small correlations with other obsessive-compulsive disorder severity measures. CONCLUSION: The obsessive-compulsive disorder field needs to discuss further improvements in the Yale-Brown Obsessive-Compulsive Scale and/or continue to search for better measures of obsessive-compulsive disorder severity.

Electrical stimulation of the inferior thalamic peduncle in the treatment of major depression and obsessive compulsive disorders.

OBJECTIVE: Stimulation of the inferior thalamic peduncle (ITP) is emerging as a promising new therapeutic target in certain psychiatric disorders. The circuitry that includes the nonspecific thalamic system (NSTS), which projects via the ITP to the orbitofrontal cortex (OFC), is involved in the physiopathology of major depression disorder (MDD) and obsessive compulsive disorder (OCD). The safety and efficacy of chronic ITP stimulation in cases of MDD and OCD refractory to medical treatment is presented. MATERIALS AND METHODS: Six patients with OCD and one with MDD were implanted with tetrapolar deep brain stimulation electrodes in the ITP (x = 3.5 mm lateral to the ventricular wall, y = 5 mm behind the anterior commissure, and z = at the intercommissural plane, i.e., anterior commissure-posterior commissure [AC-PC] level). The effect of chronic stimulation at 130 Hz, 450 µs, and 5.0 V on OCD was evaluated before and 3, 6, and 12 months after initiation of electrical stimulation through the Yale-Brown Obsessive Compulsive Scale, Hamilton Depression Rating Scale, and Global Assessment of Function scale. RESULTS: Chronic ITP electrical stimulation in OCD patients decreased the mean Yale-Brown Obsessive Compulsive Scale score to around 51% for the group at the 12-month follow-up, and increased the mean Global Assessment of Function scale score to 68% for a significant improvement (P = 0.026). Three of 6 patients returned to work. The Hamilton Depression Rating Scale score of the only patient with MDD treated to date went from 42 to 6. This condition of the patient, who had been incapacitated for 5 years prior to surgery, has not relapsed for 9 years. Three OCD patients with drug addiction continued to consume drugs in spite of their improvement in OCD. CONCLUSION: Deep brain stimulation in the ITP is safe and may be effective in the treatment of OCD. A multicenter evaluation of the safety and efficacy of ITP in OCD is currently in process.

Response of symptom dimensions in obsessive-compulsive disorder to treatment with citalopram or placebo

OBJECTIVE: There is increasing evidence that the symptoms of obsessive-compulsive disorder lie on discrete dimensions. Relatively little work has, however, explored the relationship between such factors and response to pharmacotherapy. METHOD: Data from a multi-site randomized placebo-controlled study of citalopram in obsessive-compulsive disorder were analyzed. Factor analysis of individual items and symptom categories of the Yale-Brown Obsessive-Compulsive Scale Checklist were undertaken, and the impact of symptom dimensions on treatment outcomes was analysed. RESULTS: Factor analysis of Yale-Brown Obsessive-Compulsive Scale Checklist individual items yielded 5 factors (contamination/cleaning, harm/checking, aggressive/sexual/religious, hoarding/symmetry, and somatic/hypochondriacal). Hoarding/symmetry was associated with male gender, longer duration of obsessive-compulsive disorder and early onset, whereas contamination/cleaning was associated with female gender. Citalopram was more effective than placebo, but high scores on the symmetry/hoarding and contamination/cleaning subscales predicted worse outcome at the end of study while high scores on the aggressive/religious/sexual subscale predicted better outcome. Factor analysis of Yale-Brown Obsessive-Compulsive Scale Checklist symptom clusters yielded a 4 factor solution, but confirmed that symmetry/ordering was associated with male gender, early onset, and long duration of obsessive-compulsive disorder while high scores on the hoarding subscale predicted worse response to pharmacotherapy. CONCLUSION: Citalopram shows good efficacy across the range of obsessive-compulsive disorder symptom dimensions. The relatively worse response of symmetry/hoarding to a selective serotonin reuptake inhibitor is consistent with other evidence that this symptom dimension is mediated by the dopamine system. There may be associations between symmetry/hoarding, male gender, early onset, tics, and particular...

OBJETIVO: Há crescentes evidências de que os sintomas do transtorno obsessivo-compulsivo residem em dimensões discretas. Alguns estudos têm sugerido que esses fatores possuem suportes neurobiológicos específicos. No entanto, poucos trabalhos têm explorado a relação entre tais fatores e a resposta à farmacoterapia. MÉTODO: Foi realizada a análise fatorial dos itens individuais e categorias de sintomas do checklist da Escala de Obsessão e Compulsão de Yale-Brown e foi analisado o impacto da dimensão dos sintomas no desfecho dos tratamentos. RESULTADOS: A análise fatorial exploratória dos itens individuais da Escala de Obsessão e Compulsão de Yale-Brown produziu cinco fatores (contaminação/limpeza, dano/verificação, agressividade/sexual/religioso, colecionismo/simetria e somático/hipocondríaco). Colecionismo/simetria foi associado ao sexo masculino, longa duração do transtorno obsessivo-compulsivo e início precoce, ao passo que contaminação/limpeza foi associado ao sexo feminino. O citalopram foi mais eficaz do que placebo, mas altos escores nas subescalas de simetria/colecionismo e de contaminação/limpeza predisseram desfecho pior ao final do estudo, ao passo que altos escores na subescala agressividade/sexual/religioso predisseram melhor desfecho. Uma análise fatorial de sintomas do checklist da Escala de Obsessão e Compulsão de Yale-Brown produziu uma solução com quatro fatores, mas confirmou que simetria/ordenação estava associado ao sexo masculino, início precoce e longa duração do transtorno obsessivo-compulsivo, enquanto altos escores na subescala colecionismo predisseram uma resposta pior à farmacoterapia. CONCLUSÃO: O citalopram demonstra boa eficácia ao longo das dimensões do espectro de sintomas do transtorno obsessivo-compulsivo. A resposta relativamente pior de simetria/colecionismo a um inibidor seletivo da recaptação da serotonina é consistente com outras evidências de que essa dimensão de sintomas é mediada pelo sistema...