Does night shift, stress or both make us dumber?
KeywordsPublic Health Cognitive Impairment Patient Outcome Emergency Medicine Safety Measure
Recognizing that the way intensivist work has an impact on their functioning is an important step forward for both the health of patients and intensivists. Therefore the study by Maltese et al. is important . However I wonder whether the right controls have been used. The proper control would be a test at the end of a day shift. Taking care of critically ill patients is also stressful during the daytime. There is no doubt that stress has a negative effect on cognition . It would not be surprising if intensivists perform worse during or at the end of a stressful working day. The importance of stress as a factor is supported by some of the presented data. The cognitive flexibility is increased in some groups in Figs. 2 and 3. Animal data also suggest that stress increases cognitive flexibility . And there is no relation between hours slept during the shift and cognitive impairment also suggesting an additional factor. This is important for the interpretation of the data. If the impaired cognition indeed has an effect on patient outcome, we have to take precautionary measures. When the effect is caused by stress and night shifts both alike, we have to think of other safety measures than reducing or shortening night shifts.