title: Distinct functional networks associated with improvement of affective symptoms and cognitive function during citalopram treatment in geriatric depression.
abstract: Variability in the affective and cognitive symptom response to antidepressant treatment has been observed in geriatric depression. The underlying neural circuitry is poorly understood. This study evaluated the cerebral glucose metabolic effects of citalopram treatment and applied multivariate, functional connectivity analyses to identify brain networks associated with improvements in affective symptoms and cognitive function. Sixteen geriatric depressed patients underwent resting positron emission tomography (PET) studies of cerebral glucose metabolism and assessment of affective symptoms and cognitive function before and after 8 weeks of selective serotonin reuptake inhibitor treatment (citalopram). Voxel-wise analyses of the normalized glucose metabolic data showed decreased cerebral metabolism during citalopram treatment in the anterior cingulate gyrus, middle temporal gyrus, precuneus, amygdala, and parahippocampal gyrus. Increased metabolism was observed in the putamen, occipital cortex, and cerebellum. Functional connectivity analyses revealed two networks which were uniquely associated with improvement of affective symptoms and cognitive function during treatment. A subcortical-limbic-frontal network was associated with improvement in affect (depression and anxiety), while a medial temporal-parietal-frontal network was associated with improvement in cognition (immediate verbal learning/memory and verbal fluency). The regions that comprise the cognitive network overlap with the regions that are affected in Alzheimer's dementia. Thus, alterations in specific brain networks associated with improvement of affective symptoms and cognitive function are observed during citalopram treatment in geriatric depression.
authors.affiliation: Rotman Research Institute, Baycrest Centre, Toronto, Ontario, Canada.
authors.forename: Andreea Oliviana
authors.initials: AO
authors.lastname: Diaconescu
authors.forename: Elisse
authors.initials: E
authors.lastname: Kramer
authors.forename: Carol
authors.initials: C
authors.lastname: Hermann
authors.forename: Yilong
authors.initials: Y
authors.lastname: Ma
authors.forename: Vijay
authors.initials: V
authors.lastname: Dhawan
authors.forename: Thomas
authors.initials: T
authors.lastname: Chaly
authors.forename: David
authors.initials: D
authors.lastname: Eidelberg
authors.forename: Anthony Randal
authors.initials: AR
authors.lastname: McIntosh
authors.forename: Gwenn S
authors.initials: GS
authors.lastname: Smith
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D018687:Antidepressive Agents, Second-Generation / Q000627:therapeutic use*; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism; D015283:Citalopram / Q000627:therapeutic use*; D003072:Cognition Disorders / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000209:etiology; D003863:Depression / Q000150:complications / Q000000981:diagnostic imaging / Q000188:drug therapy*; D005260:Female; D019788:Fluorodeoxyglucose F18 / Q000378:metabolism; D005853:Geriatrics; D005947:Glucose / Q000378:metabolism; D006801:Humans; D008297:Male; D008609:Mental Status Schedule; D008875:Middle Aged; D009483:Neuropsychological Tests; D049268:Positron-Emission Tomography; D011930:Reaction Time / Q000187:drug effects
chemical_list: D018687:Antidepressive Agents, Second-Generation; D015283:Citalopram; D019788:Fluorodeoxyglucose F18; D005947:Glucose