Altered Regional Cerebral Blood Flow Associated with Mood and Sleep in Shif Workers: Cerebral Perfusion Magnetic Resonance Imaging Study

Background and Purpose Shif work disrupts the body’s circadian rhythms and increases the risk of health problems. Despite evidence of neuropsychological disturbances in shif workers (SW), the brain functional status as measured by brain perfusion in chronic shif work has not been evaluated previously. We investigated the regional cerebral blood fow (rCBF) in SW using perfusion MRI (pMRI) and evaluated the relationships between altered rCBF and sleep, mood, psychometric measures, and quality of life. Methods Fifteen rotational SW and 15 day workers (DW) were enrolled. The participants were all female nurses working at a university-afliated hospital. During 2 weeks of actigraphy they underwent pMRI scanning and psychometric testing on the last day immediately after working. Demographic characteristics, insomnia, daytime sleepiness, and mood were compared between the groups. Results Te participants were aged 35.3±2.9 years (mean±SD) and had been performing their current work for more than 2 years. Te demographic characteristics did not difer between SW and DW, but the levels of insomnia, anxiety, depression, and hyperactivity-restlessness in psychometric measures were higher in SW than in DW. Cerebral perfusion in SW was signifcantly decreased in the cuneus, fusiform/parahippocampal gyri, and cerebellum of the right hemisphere, while it was increased in the inferior occipital gyrus of the lef hemisphere. Perfusion changes in SW were signifcantly correlated with depression and insomnia severity. Te onset and duration irregularity of sleep among SW were related to insomnia, mood, hyperactivity/restlessness, and quality of life. Conclusions SW experience considerably more insomnia and mood disturbances than do DW, and this is signifcantly related to perfusion changes in multiple brain areas. KCI Citation Count: 6