Structural and functional brain alterations in obstructive sleep apnea: a multimodal meta-analysis.

OBJECTIVES: Obstructive sleep apnea (OSA) is a disease with high prevalence, which reportedly influences our eyes, brain, cardiovascular system and endocrine metabolism system. Much of these symptoms are thought to be associated with damage to the brain. However, the basic neural pathophysiologic mechanism underlying these deficits is unclear. In this study, we investigate the specific and common neurostructural/functional abnormalities in OSA patients comparing with healthy people by conducting separate and multimodal meta-analysis of structural and functional magnetic resonance imaging studies.
METHOD: We search data from the original studies, extract height, coordinates of the peaks of the reported volumetric abnormalities, and recreate a map of the effect sizes of the differences between patients and controls. We use the anisotropic effect-size version of Signed Differential Mapping (AES-SDM) to clarify the robust regions in our brain when suffering from OSA. RESULT: We find shared changes in the orbital frontal cortex (OFC), which showed both decreased gray matter volume (GMV) and functional response in OSA patients; as well as GMV of the bilateral anterior cingulate/paracingulate gyri (ACC/ApCC) and hippocampus/parahippocompalgyrus (Hippo/PHG), the orbital frontal cortex (OFC) and Left cerebellum VI decrease. The dorsolateral prefrontal cortex (DLPFC) exhibited hypoactivation relative to controls, whereas the insula showed hyperactivation.
CONCLUSION: We demonstrated the significant alterations of brain structural and functional response in OSA patients. These changes give us a description about underlying neural alterations in OSA patients and may explain the psychic disorders, memory deficits, cardiovascular abnormalities and endocrine metabolism system problems, suggesting the early diagnose and treatment.