Xudong Yao1, Zhiyang Yin2, Fang Liu1, Shengnan Wei3, Yifang Zhou4, Xiaowei Jiang5, Yange Wei2, Ke Xu6, Fei Wang7, Yanqing Tang8. 1. Department of Psychiatry, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, PR China; The 7th People's Hospital, Dalian, Liaoning, PR China. 2. Department of Psychiatry, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, PR China. 3. Department of Psychiatry, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, PR China; Department of Radiology, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, PR China. 4. Department of Psychiatry, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, PR China; Department of Geriatric Medicine, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, PR China. 5. Department of Psychiatry, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, PR China; Brain Function Research Section, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, PR China. 6. Department of Radiology, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, PR China. 7. Department of Psychiatry, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, PR China; Department of Radiology, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, PR China; Brain Function Research Section, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, PR China. Electronic address: fei.wang@cmu.edu.cn. 8. Department of Psychiatry, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, PR China; Department of Geriatric Medicine, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, PR China; Brain Function Research Section, First Affiliated Hospital, China Medical University, Shenyang, Liaoning, PR China. Electronic address: yanqingtang@163.com.
Abstract
BACKGROUND: Bipolar depression (BD) is easily misdiagnosed as unipolar depression (UD) or major depressive disorder (MDD) because the depressive symptoms can overlap. Regional homogeneity (ReHo), a measure commonly used for analyzing resting-state fMRI data, has been applied to the study of various neuropsychiatric disorders. However, to date, studies directly comparing BD and UD using ReHo have been relatively scarce. Further investigation is needed to study the latent pathophysiological mechanisms of BD and UD. METHODS: Fifty-five patients with BD and 76 patients with UD, as well as 113 healthy controls (HC), underwent resting-state functional magnetic resonance imaging (fMRI). We compared the voxel-wise ReHo across the whole brain for subjects in each of the three groups. RESULTS: Significant differences were found in the left frontal cluster (LFC) across the three groups. There were differences between BD and UD in the LFC and left temporal cluster (LTC). In addition, differences between UD and HC existed in the LFC and the occipital cluster (OC). When comparing BD subjects with HC subjects, significant differences were found in all three clusters. No correlations were observed between the 17-item Hamilton Depression Rating Scale (HDRS-17) scores or sub-scores and the ReHo values of BD or UD patients. CONCLUSION: ReHo values in the LFC differed significantly among BD, UD, and HC subjects. ReHo in the LTC showed significant differences between BD and UD that might serve as neuroimaging markers of BD. Further, BD and UD shared ReHo changes in the cuneus, suggesting that the cuneus might provide a depressive state neuroimaging marker of BD and UD patients.
BACKGROUND:Bipolar depression (BD) is easily misdiagnosed as unipolar depression (UD) or major depressive disorder (MDD) because the depressive symptoms can overlap. Regional homogeneity (ReHo), a measure commonly used for analyzing resting-state fMRI data, has been applied to the study of various neuropsychiatric disorders. However, to date, studies directly comparing BD and UD using ReHo have been relatively scarce. Further investigation is needed to study the latent pathophysiological mechanisms of BD and UD. METHODS: Fifty-five patients with BD and 76 patients with UD, as well as 113 healthy controls (HC), underwent resting-state functional magnetic resonance imaging (fMRI). We compared the voxel-wise ReHo across the whole brain for subjects in each of the three groups. RESULTS: Significant differences were found in the left frontal cluster (LFC) across the three groups. There were differences between BD and UD in the LFC and left temporal cluster (LTC). In addition, differences between UD and HC existed in the LFC and the occipital cluster (OC). When comparing BD subjects with HC subjects, significant differences were found in all three clusters. No correlations were observed between the 17-item Hamilton Depression Rating Scale (HDRS-17) scores or sub-scores and the ReHo values of BD or UD patients. CONCLUSION: ReHo values in the LFC differed significantly among BD, UD, and HC subjects. ReHo in the LTC showed significant differences between BD and UD that might serve as neuroimaging markers of BD. Further, BD and UD shared ReHo changes in the cuneus, suggesting that the cuneus might provide a depressive state neuroimaging marker of BD and UD patients.