title: A longitudinal study of fronto-limbic brain structures in patients with bipolar I disorder during lithium treatment.
abstract: In order to assess the association between therapeutic response to lithium treatment and fronto-limbic brain structures' volumes in bipolar I patients (BPI) 24 BPI and 11 healthy comparisons underwent MRI scans at baseline and 4 weeks later. The BPIs received lithium during the 4 week period with a goal of achieving therapeutic blood levels of >0.5 mEq/L (mean level 0.67 mEq/L). Mood symptoms were rated with the Hamilton Depression and the Young Mania Rating Scales at baseline and after 4 weeks, and response was defined as >50% decrease on either scale. Hippocampus, amygdala, prefrontal (PFC), dorsolateral prefrontal (DLPFC), and anterior cingulate cortex (ACC) volumes were obtained by Freesurfer image analysis suite. According to baseline symptoms and treatment response, patients were assigned to three groups: euthymics (n=6), responders (n=12) and non-responders (n=6). Taken over both time periods, non-responders had smaller right amygdala than healthy comparisons and euthymic BPI (p=0.035 and p=0.003, respectively). When baseline and after treatment volumes were compared, there was a significant enlargement in left PFC and left DLPFC in BPI who responded to treatment (p=0.002 and p=0.006, respectively). Left hippocampus and right ACC volumes decreased in non-responders (p=0.02 and p=0.0001, respectively). According to the findings decreased left hippocampus and right ACC volumes may be markers of non-response to lithium amongst BPI. Smaller right amygdala may reflect symptomatic remission and be a marker of treatment non-response. Increases in left PFC and left DLPFC as a result of lithium treatment may relate to lithium's neurotrophic effects.
authors.affiliation: Department of Psychiatry and Behavioral Sciences, University of Texas Health Science Center at Houston, Houston, TX, United States. drselek@yahoo.com
authors.forename: Salih
authors.initials: S
authors.lastname: Selek
authors.forename: Mark
authors.initials: M
authors.lastname: Nicoletti
authors.forename: Giovana B
authors.initials: GB
authors.lastname: Zunta-Soares
authors.forename: John P
authors.initials: JP
authors.lastname: Hatch
authors.forename: Fabiano G
authors.initials: FG
authors.lastname: Nery
authors.forename: Koji
authors.initials: K
authors.lastname: Matsuo
authors.forename: Marsal
authors.initials: M
authors.lastname: Sanches
authors.forename: Jair C
authors.initials: JC
authors.lastname: Soares
mesh_terms: D000328:Adult; D000339:Affect; D001714:Bipolar Disorder / Q000188:drug therapy* / Q000503:physiopathology*; D005260:Female; D006179:Gyrus Cinguli / Q000187:drug effects* / Q000503:physiopathology; D006624:Hippocampus / Q000187:drug effects* / Q000503:physiopathology; D006801:Humans; D018020:Lithium Compounds / Q000494:pharmacology / Q000627:therapeutic use*; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging; D008297:Male; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D018020:Lithium Compounds
keywords: Bipolar disorder; Hippocampus; Lithium; Prefrontal cortex