Evidence of White Matter Integrity Changes in the Anterior Cingulum Among Shift Workers: A Cross-Sectional Study

Abstract

Introduction We investigated the white matter integrity in shift and non-shift workers and its associations with sleep and activity. Methods Diffusion tensor imaging (DTI) was performed on 61 shift workers and 31 non-shift workers. Their sleep and activity profiles were assessed using the Pittsburgh Sleep Quality Index (PSQI), sleep diaries, and actigraphy. Fractional anisotropy (FA) (a measure of white matter integrity) was calculated using DTI tractography. Results Shift workers exhibited higher FA values in the bilateral anterior cingulum than did non-shift workers. An increased FA in the right anterior cingulum was correlated with poor sleep quality (ie, a high PSQI score) in shift workers. An increased FA in the right anterior cingulum was also correlated with higher actigraphic activity indices (the mesor and M10 indices) in shift workers. Discussion The white matter integrity of the anterior cingulum was altered in shift workers, perhaps in association with sleep and activity disturbances.

Early life stress, sleep disturbances, and depressive symptoms during adolescence: The role of the cingulum bundle

“…For example, Cullen et al (2020) examined the associations between FA across numerous tracts and several dimensions of depression (e.g., lassitude, appetite changes, traumatic intrusion) in adolescents with depression and found that greater right CGC FA was associated with greater lassitude, which is characterized by feelings of exhaustion, low energy, sleepiness, difficulty getting going, and feeling worse in the morning ( Cullen et al, 2020 ). In a study with adults, Lee et al (2022) found that shift-workers, who regularly experience sleep disturbances due to the desynchronization of their circadian rhythm and homeostatic sleep pressure, exhibited greater right CGC FA than did non-shift-workers. Moreover, in shift-workers, greater right CGC FA was positively correlated with multiple indices of poor sleep quality, including poorer subjective sleep, whereas the opposite pattern (higher CGC FA, better sleep quality) was observed in non-shift-workers.…”

Emotional Dysregulation in Shift Workers

“…Regarding white matter integrity, shift workers exhibited higher fractional anisotropy (FA) values in the bilateral anterior cingulum compared with non-shift workers; increased FA in the right anterior cingulum was correlated with poor sleep quality [39]. A resting-state fMRI study showed that shift workers exhibited altered functional connectivity in the salience network.…”

Alterations of functional brain activity and connectivity in female nurses working on long‐term shift

“…Moreover, grey matter alterations in the left postcentral gyrus mediated the influence of sleep disturbance on the depressive symptoms of the subjects. Another study (Lee et al., 2022 ) compared the differences in white matter structure of shift workers and non‐shift workers, finding that the shift workers exhibited higher fractional anisotropy in the bilateral anterior cingulum, and that the increased fractional anisotropy in the right anterior cingulum was correlated with the poor sleep quality of shift workers. These studies provided preliminary knowledge of shift work affecting the brain structural plasticity of workers, which was generally attributed to the shift work‐induced sleep deprivation and the resulting disruption of the internal environment.…”