Cerebral glucose metabolism in bipolar disorder: A voxel‐based meta‐analysis of positron emission tomography studies

BACKGROUND: Previous positron emission tomography studies have reported the changes of cerebral glucose metabolism in bipolar disorder. However, the findings across studies remain controversial, containing differing results. METHODS: A systematic literature search of the PubMed, Embase, Cochrane Library, and Web of Science databases was conducted. We conducted a voxel‐wide meta‐analysis of cerebral glucose metabolism studies, using the seed‐based mapping approach, in patients with bipolar disorder (BD). RESULTS: We identified 7 studies suitable for inclusion, which included a total of 126 individuals with BD and 160 healthy controls. The most consistent and robust findings were an increase in cerebral glucose metabolism in the right precentral gyrus and a decrease in the left superior temporal gyrus, left middle temporal gyrus, and cerebellum. Additionally, the sex distribution and illness duration had significant moderating effects on cerebral glucose metabolism alterations. CONCLUSIONS: Cerebral glucose metabolism alterations in these brain regions are likely to reflect the disease‐related functional abnormalities such as emotion and cognition. These findings contribute to a better understanding of the neurobiological underpinnings of bipolar disorder. Limitations. This study was done at a study level and cannot be addressed at the patient level. Subgroup analysis of BD I and BD II is not possible due to limited literature data.