A longitudinal functional neuroimaging study in medication-naïve depression after antidepressant treatment

• Published in: PloS one 2015-03, Vol.10 (3), p.e0120828-e0120828
• Main Authors: Tomioka, Hiroi, Yamagata, Bun, Kawasaki, Shingo, Pu, Shenghong, Iwanami, Akira, Hirano, Jinichi, Nakagome, Kazuyuki, Mimura, Masaru
• Format: Article
• Language: English
• Subjects: Adult; Aged; Antidepressants; Antidepressive Agents - therapeutic use; Bioindicators; Biomarkers; Biomarkers - blood; Bipolar disorder; Brain Mapping; Case-Control Studies; Cognitive ability; Correlation analysis; Depressive Disorder, Major - blood; Depressive Disorder, Major - diagnosis; Depressive Disorder, Major - drug therapy; Depressive Disorder, Major - physiopathology; Diagnosis; Drugs; Female; Functional Neuroimaging; Humans; Infrared spectroscopy; Longitudinal Studies; Male; Medical imaging; Mental depression; Middle Aged; Near infrared radiation; Near infrared spectroscopy; Neuroimaging; Neurology; Neuropsychological Tests; NMR; Nuclear magnetic resonance; Oxyhemoglobins - metabolism; Prefrontal Cortex - drug effects; Prefrontal Cortex - physiopathology; Psychiatric Status Rating Scales; Spectroscopy, Near-Infrared; Temporal Lobe - drug effects; Temporal Lobe - physiopathology
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0120828

Recent studies have indicated the potential clinical use of near infrared spectroscopy (NIRS) as a tool in assisting the diagnosis of major depressive disorder (MDD); however, it is still unclear whether NIRS signal changes during cognitive task are state- or trait-dependent, and whether NIRS could be a neural predictor of treatment response. Therefore, we conducted a longitudinal study to explore frontal haemodynamic changes following antidepressant treatment in medication-naïve MDD using 52-channel NIRS. This study included 25 medication-naïve individuals with MDD and 62 healthy controls (HC). We performed NIRS scans before and after antidepressant treatment and measured changes of [oxy-Hb] activation during a verbal fluency task (VFT) following treatment. Individuals with MDD showed significantly decreased [oxy-Hb] values during a VFT compared with HC in the bilateral frontal and temporal cortices at baseline. There were no [oxy-Hb] changes between pre- and post-antidepressant treatment time points in the MDD cohort despite significant improvement in depressive symptoms. There was a significant association between mean [oxy-Hb] values during a VFT at baseline and improvement in depressive symptoms following treatment in the bilateral inferior frontal and middle temporal gyri in MDD. These findings suggest that hypofrontality response to a VFT may represent a potential trait marker for depression rather than a state marker. Moreover, the correlation analysis indicates that the NIRS signals before the initiation of treatment may be a biological marker to predict patient's clinical response to antidepressant treatment. The present study provides further evidence to support a potential application of NIRS for the diagnosis and treatment of depression.