The plasma concentration of copper and prevalence of depression were positively correlated in shift nurses

Several studies have reported the prevalence of depression in shift nurses to be 15%, and in some cases it may even be as high as 23%. Depression is a major cause of poor sleep quality and can impede efforts to overcome the chronic fatigue that commonly affects shift nurses. Adverse mental health issues have been confirmed in shift nurses, but few studies have investigated the underlying cause of poor mental health in different shift-nurse populations. Therefore, the aim of this study was to investigate the relationship of serum trace element levels to mental health and the tendency toward depression in shift nurses. We collected blood samples from 90 shift nurses (day, evening, and night shift) who worked in intensive care units and asked them to complete a general data questionnaire as well as the Chinese version of the Beck Depression Inventory, second edition. The night-shift nurses showed mild-to-moderate depression levels, which were significantly higher than those of the control group and other shift nurses. Night-shift nurses also had higher levels of plasma copper, ferritin, interleukin (IL)-6, and alanine aminotransferase (p < .05) than the control group and other nurses. Elevated concentrations of ferritin and IL-6 are considered important markers for the onset of depression. The results of this study suggest that plasma copper concentrations in nurses should be monitored.