Gray matter volumes in obsessive-compulsive disorder before and after fluoxetine or cognitive-behavior therapy: a randomized clinical trial.

Serotonin reuptake inhibitors and cognitive-behavior therapy (CBT) are considered first-line treatments for obsessive-compulsive disorder (OCD). However, little is known about their modulatory effects on regional brain morphology in OCD patients. We sought to document structural brain abnormalities in treatment-naive OCD patients and to determine the effects of pharmacological and cognitive-behavioral treatments on regional brain volumes. Treatment-naive patients with OCD (n=38) underwent structural magnetic resonance imaging scan before and after a 12-week randomized clinical trial with either fluoxetine or group CBT. Matched-healthy controls (n=36) were also scanned at baseline. Voxel-based morphometry was used to compare regional gray matter (GM) volumes of regions of interest (ROIs) placed in the orbitofrontal, anterior cingulate and temporolimbic cortices, striatum, and thalamus. Treatment-naive OCD patients presented smaller GM volume in the left putamen, bilateral medial orbitofrontal, and left anterior cingulate cortices than did controls (p<0.05, corrected for multiple comparisons). After treatment with either fluoxetine or CBT (n=26), GM volume abnormalities in the left putamen were no longer detectable relative to controls. ROI-based within-group comparisons revealed that GM volume in the left putamen significantly increased (p<0.012) in fluoxetine-treated patients (n=13), whereas no significant GM volume changes were observed in CBT-treated patients (n=13). This study supports the involvement of orbitofronto/cingulo-striatal loops in the pathophysiology of OCD and suggests that fluoxetine and CBT may have distinct neurobiological mechanisms of action.

The drug-naïve OCD patients imaging genetics, cognitive and treatment response study: methods and sample description / Estudo de genética, imagem, cognição e resposta a tratamento em pacientes com TOC virgens de tratamento: métodos e descrição da amostra

OBJECTIVE: To describe a protocol that was based on an integrative neurobiological model of scientific investigation to better understand the pathophysiology of obsessive-compulsive disorder and to present the clinical and demographic characteristics of the sample. METHOD: A standardized research protocol that combines different methods of investigation (genetics, neuropsychology, morphometric magnetic resonance imaging and molecular neuroimaging of the dopamine transporter) obtained before and after treatment of drug-naïve adult obsessive-compulsive disorder patients submitted to a sequentially allocated 12-week clinical trial with a selective serotonin reuptake inhibitor (fluoxetine) and group cognitive-behavioral therapy. RESULTS: Fifty-two treatment-naïve obsessive-compulsive disorder patients entered the clinical trial (27 received fluoxetine and 25 received group cognitive-behavioral therapy). At baseline, 47 blood samples for genetic studies, 50 neuropsychological evaluations, 50 morphometrical magnetic resonance images and 48 TRODAT-1 single-photon emission computed tomography (SPECT) exams were obtained. After 12 weeks, 38 patients completed the protocol (fluoxetine = 20 and GCBT = 18). Thirty-eight neuropsychological evaluations, 31 morphometrical magnetic resonance images and 34 TRODAT-1 SPECT exams were obtained post-treatment. Forty-one healthy controls matched for age, gender, socioeconomic status, level of education and laterality were submitted to the same research procedures at baseline. CONCLUSION: The comprehensive treatment response protocol applied in this project allowing integration on genetic, neuropsychological, morphometrical and molecular imaging of the dopamine transporter data in drug-naïve patients has the potential to generate important original information on the neurobiology of obsessive-compulsive disorder, and at the same time be clinically meaningful.

OBJETIVO: Descrever um protocolo integrativo de investigação neurobiológica para melhor compreender as bases patofisiológicas do transtorno obsessivo-compulsivo e apresentar as características clínicas e demográficas da amostra. MÉTODO: Protocolo padronizado que combina diferentes modalidades de investigação (genética, neuropsicologia, ressonância magnética cerebral e imagem molecular do transportador de dopamina) obtidas antes e depois do tratamento em pacientes com transtorno obsessivo-compulsivo nunca expostos à medicação submetidos a um ensaio clínico comparando um inibidor seletivo da recaptação de serotonina (fluoxetina) e terapia cognitivo-comportamental em grupo. RESULTADOS: Cinquenta e dois pacientes com transtorno obsessivo-compulsivo entraram no ensaio clínico (27 no grupo fluoxetina e 25 no grupo de terapia). No início, foram realizadas 47 coletas de sangue para genética, 50 avaliações neuropsicológicas, 50 ressonâncias magnéticas cerebrais e 48 exames de tomografia computadorizada por emissão de fóton único (SPECT) com TRODAT-1. Depois de 12 semanas, 38 pacientes terminaram o protocolo (20 no grupo de fluoxetina e 18 no grupo de terapia). Trinta e oito reavaliações neuropsicológicas, 31 ressonâncias magnéticas de crânio e 34 exames de SPECT foram obtidos após o tratamento. Quarenta e um controles pareados foram submetidos ao mesmo protocolo inicial. CONCLUSÃO: Os dados genéticos, neuropsicológicos, volumétricos e moleculares do transportador de dopamina aliados à resposta a tratamento podem tanto gerar informações importantes a respeito da neurobiologia do transtorno obsessivo-compulsivo quanto ter uma aplicação clínica.

Physiological responses to brain stimulation during limbic surgery: further evidence of anterior cingulate modulation of autonomic arousal.

BACKGROUND: In view of conflicting neuroimaging results regarding autonomic-specific activity within the anterior cingulate cortex (ACC), we investigated autonomic responses to direct brain stimulation during stereotactic limbic surgery. METHODS: Skin conductance activity and accelerative heart rate responses to multi-voltage stimulation of the ACC (n = 7) and paralimbic subcaudate (n = 5) regions were recorded during bilateral anterior cingulotomy and bilateral subcaudate tractotomy (in patients that had previously received an adequate lesion in the ACC), respectively. RESULTS: Stimulations in both groups were accompanied by increased autonomic arousal. Skin conductance activity was significantly increased during ACC stimulations compared with paralimbic targets at 2 V (2.34 +/- .68 [score in microSiemens +/- SE] vs. .34 +/- .09, p = .013) and 3 V (3.52 +/- .86 vs. 1.12 +/- .37, p = .036), exhibiting a strong "voltage-response" relationship between stimulus magnitude and response amplitude (difference from 1 to 3 V = 1.15 +/- .90 vs. 3.52 +/- .86, p = .041). Heart rate response was less indicative of between-group differences. CONCLUSIONS: This is the first study of its kind aiming at seeking novel insights into the mechanisms responsible for central autonomic modulation. It supports a concept that interregional interactions account for the coordination of autonomic arousal.

The drug-naïve OCD patients imaging genetics, cognitive and treatment response study: methods and sample description.

OBJECTIVE: To describe a protocol that was based on an integrative neurobiological model of scientific investigation to better understand the pathophysiology of obsessive-compulsive disorder and to present the clinical and demographic characteristics of the sample. METHOD: A standardized research protocol that combines different methods of investigation (genetics, neuropsychology, morphometric magnetic resonance imaging and molecular neuroimaging of the dopamine transporter) obtained before and after treatment of drug-naïve adult obsessive-compulsive disorder patients submitted to a sequentially allocated 12-week clinical trial with a selective serotonin reuptake inhibitor (fluoxetine) and group cognitive-behavioral therapy. RESULTS: Fifty-two treatment-naïve obsessive-compulsive disorder patients entered the clinical trial (27 received fluoxetine and 25 received group cognitive-behavioral therapy). At baseline, 47 blood samples for genetic studies, 50 neuropsychological evaluations, 50 morphometrical magnetic resonance images and 48 TRODAT-1 single-photon emission computed tomography (SPECT) exams were obtained. After 12 weeks, 38 patients completed the protocol (fluoxetine = 20 and GCBT = 18). Thirty-eight neuropsychological evaluations, 31 morphometrical magnetic resonance images and 34 TRODAT-1 SPECT exams were obtained post-treatment. Forty-one healthy controls matched for age, gender, socioeconomic status, level of education and laterality were submitted to the same research procedures at baseline. CONCLUSION: The comprehensive treatment response protocol applied in this project allowing integration on genetic, neuropsychological, morphometrical and molecular imaging of the dopamine transporter data in drug-naïve patients has the potential to generate important original information on the neurobiology of obsessive-compulsive disorder, and at the same time be clinically meaningful.