title: Longer depressive episode duration negatively influences HF-rTMS treatment response: a cerebellar metabolic deficiency?
abstract: Repetitive transcranial magnetic stimulation (rTMS) is an evidence based neurostimulation modality used to treat patients with Major Depressive Disorder (MDD). In spite that the duration of current a depressive episode has been put forward as a negative predictor for clinical outcome, little is known about the underlying neurobiological mechanisms of this phenomenon. To address this important issue, in a sample of 43 melancholic stage III treatment resistant antidepressant-free refractory MDD patients, we reanalysed regional cerebral glucose metabolism (CMRglc) before high frequency (HF)-rTMS treatment, applied to the left dorsolateral prefrontal cortex (DLPFC). Besides that a lower baseline cerebellar metabolic activity indicated negative clinical response, a longer duration of the depressive episode was a negative indicator for recovery and negatively influenced cerebellar CMRglc. This exploratory18FDG PET study is the first to demonstrate that the clinical response of HF-rTMS treatment in TRD patients may depend on the metabolic state of the cerebellum. Our observations could imply that for left DLPFC HF-rTMS non-responders other brain localisations for stimulation, more specifically the cerebellum, may be warranted.
authors.affiliation: Key Laboratory of Cognition and Personality, Faculty of Psychology, Southwest University, Chongqing, China.|Department of Psychiatry and Medical Psychology, Ghent University, De Pintelaan 185 - 9000, Ghent, Belgium.
authors.forename: Guo-Rong
authors.initials: GR
authors.lastname: Wu
authors.affiliation: Department of Psychiatry and Medical Psychology, Ghent University, De Pintelaan 185 - 9000, Ghent, Belgium. cbaeken@hotmail.com.|Department of Psychiatry, Vrije Universiteit Brussel (VUB), Universitair Ziekenhuis Brussel (UZBrussel), Laarbeeklaan 101, 1090, Brussels, Belgium. cbaeken@hotmail.com.|Ghent Experimental Psychiatry (GHEP) Lab, Ghent University, Ghent, Belgium. cbaeken@hotmail.com.
authors.forename: Chris
authors.initials: C
authors.lastname: Baeken
mesh_terms: D000328:Adult; D001921:Brain / Q000000981:diagnostic imaging / Q000378:metabolism*; D001931:Brain Mapping; D003865:Major Depressive Disorder / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000628:therapy*; D061218:Depressive Disorder, Treatment-Resistant / Q000000981:diagnostic imaging / Q000378:metabolism* / Q000628:therapy*; D005260:Female; D019788:Fluorodeoxyglucose F18; D005947:Glucose / Q000378:metabolism; D006801:Humans; D008297:Male; D049268:Positron-Emission Tomography; D019275:Radiopharmaceuticals; D050781:Transcranial Magnetic Stimulation; D016896:Treatment Outcome
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18; D005947:Glucose
keywords: 18FDG PET; Cerebellum; HF-rTMS; Major depressive disorder; Treatment-resistance