Cortical thickness abnormalities in patients with bipolar disorder: A systematic review and meta-analysis

• Published in: Journal of affective disorders 2022-03, Vol.300, p.209-218
• Main Authors: Zhu, Ziyu, Zhao, Youjin, Wen, Keren, Li, Qian, Pan, Nanfang, Fu, Shiqin, Li, Fei, Radua, Joaquim, Vieta, Eduard, Kemp, Graham J., Biswa, Bharat B., Gong, Qiyong
• Format: Article
• Language: English
• Subjects: Bipolar disorder; Bipolar Disorder - drug therapy; Brain - pathology; Cortical thickness; Humans; Magnetic resonance imaging; Magnetic Resonance Imaging - methods; Medicin och hälsovetenskap; Meta-analysis; Neuroimaging; Prefrontal Cortex - diagnostic imaging; Prefrontal Cortex - pathology; Psychoradiology; Seed-based d mapping
• ISSN: 0165-0327; 1573-2517; 1573-2517
• DOI: 10.1016/j.jad.2021.12.080

•Meta-analysis of CT differences between BD patients and HCs.•Finds CT reductions in insula, OFC and mPFC in BD patients using a new mask in SDM.•The mean age of BD patients is negatively associated with CT in the left insula.•Provides key knowledge to inform biomarker research in bipolar disorder. An increasing number of neuroimaging studies report alterations of cortical thickness (CT) related to the neuropathology of bipolar disorder (BD). We provide here a whole-brain vertex-wise meta-analysis, which may help improve the spatial precision of these identifications. A comprehensive meta-analysis was performed to investigate the differences in CT between patients with BD and healthy controls (HCs) by using a newly developed mask for CT analysis in seed-based d mapping (SDM) meta-analytic software. We used meta-regression to explore the effects of demographics and clinical characteristics on CT. This meta-review was conducted in accordance with PRISMA guideline. We identified 21 studies meeting criteria for the systematic review, of which 11 were eligible for meta-analysis. The meta-analysis comprising 649 BD patients and 818 HCs showed significant cortical thinning in the left insula extending to left Rolandic operculum and Heschl gyrus, the orbital part of left inferior frontal gyrus (IFG), the medial part of left superior frontal gyrus (SFG) as well as bilateral anterior cingulate cortex (ACC) in BD. In meta-regression analyses, mean patient age was negatively correlated with reduced CT in the left insula. All enrolled studies were cross-sectional; we could not explore the potential effects of medication and mood states due to the limited data. Our results suggest that BD patients have significantly thinner frontoinsular cortex than HCs, and the results may be helpful in revealing specific neuroimaging biomarkers of BD patients.