Cognitive functions of shift workers: paramedics and firefighters – an electroencephalography study

Abstract

Working shifts has a negative impact on employee health and cognitive efficiency. The purpose of this study was to investigate the impact of shift work on cognitive functions -attention and working memory -using both behavioural and electrophysiological measures. Methods. The study was carried out on a group of 34 shift employees (18 paramedics, 16 firefighters) and on 17 day workers. Participants performed the attention network test and the N -back task with two conditions (1-back, 2-back) while the electroencephalography signal was recorded. Results. Observations included a higher amplitude of the P200 potential in paramedics (compared to the control group), a higher amplitude of the P300 potential after work than on a day off and the lowest increase in power in the θ band after the night shift. In firefighters, lower α desynchronization and lower synchronization in the α/β band were observed after a 24-h shift. Paramedics and firefighters had longer reaction times (N -back task). Conclusions. The results suggest that paramedics experience problems with sustained attention. Paramedics process visual stimuli in a different way; after a night shift, performing the tasks required more engagement of cognitive resources. For firefighters, a decrease in visual attention functions and cognitive inhibition was observed.

Impact of Shift Work and Long Working Hours on Worker Cognitive Functions: Current Evidence and Future Research Needs

“…Moreover, in some studies, electrophysiological measures by electroencephalography and the determination in biological matrices of different hormones such as growth hormone (GH), cortisol and its precursors, prolactin (PRL), thyroid-stimulating hormone (TSH) and melatonin were also carried out in order to analyze the possible physio-pathological mechanisms underlying the observed alterations of cognitive domains. Importantly, in these studies, the potential role of different parameters that are recognized risk factors for the cognitive decline (e.g., age, family history for dementia and/or related diseases, hypertension, cerebral vasculopathies, metabolic syndrome, disorders of sleep and mood, physical inactivity, social isolation, lower education level and psychosocial factors) and that could represent confounding factors in the interpretation of the results have been often verified, albeit in quite different ways and combinations [ 7 , 8 , 21 , 25 , 26 , 27 , 30 , 31 , 32 , 33 , 34 , 35 , 36 , 37 , 38 , 39 , 40 , 41 , 42 , 43 , 44 , 45 , 46 , 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 ]. Finally, most of the articles have studied the short-term effects of shift work, while few studies have analyzed the possible impact of long-term chronic exposure on cognition [ 27 , 31 , 46 , 47 , 48 , 49 , 50 , ...…”

“…Comparable results were obtained by Adams and Venter [ 55 ] in anesthesiology trainees who showed an important decline of reaction time in psychomotor and attention cognitive functions at the end of 14 h shifts. Deterioration of cognitive efficiency following extended shifts work was also proved in paramedics and firefighters who worked 12 h and 24 h shifts, respectively [ 56 ]. Similarly, the cognitive efficiency of firefighters (assigned to different rotations of extended 15 and 24 h work shifts, including night) was significantly affected by the exposure to night work that was associated with lower scores of composite memory, verbal and visual memory, complex attention, psychomotor and motor speed [ 26 ].…”

Perception of Effects of Shiftwork Questionnaire (PESQ) among Ambulance Service Staff in Saudi Arabia: An Exploratory Factor Analysis

“…In most cases, shiftwork in the workplace involves changes in areas of deployment, rotation patterns and schedule [2] [3] [4] [5]. Due to an increasing demand for healthcare services, healthcare systems have required doctors, nurses and other health care professionals to engage in shiftwork to ensure continuity of medical services in clinical settings, emergency cases and rescue operations [2] [4] [6] [7].…”

Shifted Firefighter Health Investigation by Personal Health Insurance Record in Taiwan

“… 6 Table 1 lists recent studies on occupational injuries that are related to firefighters and shift rotations. These mainly involve sleeping, 14 , 15 depression and stress, 16 , 17 cognitive functions, 18 cancer, 19 , 20 hypertension, 21 physical activity and obesity, 22–24 metabolic syndromes, 25 and injuries and musculoskeletal disorders. 26 , 27 According to the 2154 work injuries that were recorded from 2010 to 2015 in South Korea in reference, 28 the majority of injuries concerned the upper and lower back (25.3%).…”

“… CES‐D; job dissatisfaction survey Workload, intergroup conflict, social support from a supervisor related to depressive symptoms and/or job dissatisfaction 14 2018 Iranian 60 shift work firefighters melatonin, sleepness Melatonin level change at 3:00 and 7:00 15 2017 Korea 110 shift work firefighters Pittsburgh Sleep Quality Index, the Insomnia Severity Index, the Epworth Sleepiness Score, the Stanford Sleepiness Score, the Fatigue Severity Scale, and the Berlin Questionnaire 60% of the participating firefighters had a certain degree of insomnia 17 2017 Finland firefighters Heart rate variability during shifts. Physiological load and psychological stress were temporarily high 18 2020 Poland 18 paramedics, 16 firefighters and 17 day worker EEG Higher amplitude of the P200 and P300 potential 19 2018 Danish 11,775 firefighters mortality ratios Death from stomach cancer increased 21 2016 USA 330 firefighters Blood pressure Sixteen 24-h shifts had 5.0 mmHg higher DBP 22 2016 Australia Thirty-four salaried firefighters wore an Actical accelerometer for 28 consecutive days 70% light-intensity physical activity 25 2016 Germany 97 firefigh...…”