Changes in Cerebral Cortex and Limbic Brain Functions after Short-Term Paroxetine Treatment in Panic Disorder: An [¹⁸F]FDG-PET Pilot Study

Abstract

ObjectivePanic disorder (PD) is a common and often chronic psychiatric illness, and serotonin-specific reuptake inhibitors (SSRIs) are the drugs of choice for the treatment of PD. Previous studies suggested the cerebral cortex and limbic brain structures played a major role in the development of PD, but the therapeutic effect of SSRIs on specific brain structures remains unclear in PD. We examined the changes in PD patients' glucose metabolism using the [18F] Fluorodeoxy-glucose-positron emission tomography (FDG-PET) before and after 12 weeks of paroxetine treatment.MethodsWe assessed the brain glucose metabolism of 5 PD patients, using the [18F]FDG-PET, and treated them with paroxetine (12.5-37.5 mg/day) for 12 weeks. Then, we compared before and after treatment PET images of the patients, using voxel-based statistical analysis and a post hoc regions of interest analysis. Furthermore, we measured the patients' clinical variables, including information from the Panic Disorder Severity Scale (PDSS), Clinical Global Impression for Severity (CGI-S), and Hamilton Anxiety Rating Scale (HAMA).ResultsAfter 12 weeks of paroxetine treatment, the patients showed significant clinical improvement in terms of PDSS, CGI-S and HAMA scores (12.8±1.8 vs. 3.8±2.3, 4.6±0.5 vs. 2.0±1.4, and 15.2±4.0 vs. 5.0±1.2, respectively; all p values<0.05). After treatment, patients' glucose metabolism increased significantly in global brain areas: the right precentral gyrus, right middle frontal gyrus, right amygdala, right caudate body, right putamen, left middle frontal gyrus, left precentral gyrus, left insula, left parahippocampal gyrus, and left inferior frontal gyrus (All areas were significant at uncorrected p<0.001 and cluster level corrected p<0.05).ConclusionIn these PD patients, cerebral cortex and limbic brain functions changed after short-term treatment with paroxetine. The therapeutic action of paroxetine may be related to altered glucose metabolism at both the cerebral cortex and limbic brain areas.

The Effects of Taekwondo Training on Brain Connectivity and Body Intelligence

“…Hodzic et al 35 suggested that the right superior and inferior parietal cortices were involved in the analysis of body-related information. 36 In the current study, in the TKD group, the cerebellum was functionally connected to the right frontal cortex, while in the control group, the cerebellum was functionally connected to the left frontal and parietal cortices. The right hemisphere is known to be associated with the sense of space and body perception.…”

Neurostructural abnormalities in pediatric anxiety disorders

“…Also, consistent with the notion that this region plays a compensatory function in the central fear circuit are findings of treatment-associated increases in activation of the VLPFC in both adults and youth. For example, treatment with the SSRI paroxetine is associated with increases in metabolic activity in this region in adults with anxiety disorders (Sim et al, 2010) and CBT in adults with anxiety disorders results in increased connectivity between the inferior frontal gyrus and the amygdala as well as the anterior cingulate cortex (Kircher et al, 2013). Additionally, one small study of adolescents with GAD revealed that successful treatment with either the SSRI fluoxetine or CBT was associated with increases in functional activation within the VLPFC (Maslowsky et al, 2010).…”

Neuroanatomic Abnormalities in Adolescents With Generalized Anxiety Disorder: A Voxel-Based Morphometry Study

“…Finally, in adolescents with GAD, increased gray matter volumes were observed in precentral gyrus. To date, multiple studies have noted increased functional activity in precentral gyrus using positron emission tomography (PET) in adults with GAD, adults with generalized social phobia, and in adults with panic disorder . Importantly, this region is not only involved in motor and somatosensory functions, but is also involved in processes which may be central to anxiogenesis.…”

“…To date, multiple studies have noted increased functional activity in precentral gyrus using positron emission tomography (PET) in adults with GAD, [58] adults with generalized social phobia, [59] and in adults with panic disorder. [60] Importantly, this region is not only involved in motor and somatosensory functions, but is also involved in processes which may be central to anxiogenesis. For example, the precentral gyrus has been associated with the modulation of anticipatory threat [61] and has been linked with anxious attachment styles.…”