OBJECTIVES Synthesis of melatonin follows a circadian cycle, with high melatonin levels during the night and low levels during the day. Light exposure at night has been hypothesised as one of potential mechanisms of breast carcinogenesis in the night shift workers through inhibition of melatonin synthesis. The aim of the study was to examine a number of determinants for night shift work in rela...

Effects of shift work on physiological parameters and autonomic nervous-adrenal system were studied on six hospital nurses. Their body temperature, heart rate, blood pressure, fluctuation in ECG R-R intervals, serum catecholamines and cortisol, and subjective fatigue ratings before and after day, evening and night shift were determined. Furthermore, mean heart rates, walk steps, estimated energ...

STUDY OBJECTIVES To study the adaptation and readaptation processes to 1 week of night work (6:30 PM to 6:30 AM) followed by 1 week of day work (6:30 AM to 6:30 PM). DESIGN Part of a randomized, placebo-controlled, crossover field study. Here, data from the placebo arm are presented. SETTING Oil rig in the North Sea. Work schedule: 2 weeks on a 12-hour shift, with the first week on the nigh...

Prolonged night shift is associated with high burnout rate, but the physiological effects of a 16 h shift remain undetermined. Here we evaluated fatigue and stress via salivary assays to determine the correlation between stress and fatigue and prolonged night shifts. Twenty-five nurses (9 men, 16 women; 16 h night shift (n = 13), 8 h day shift (n = 12)) from Juntendo University Koshigaya Hospit...

OBJECTIVE To estimate the association between night-shift work and high cardiovascular risk. METHODS Cross-sectional study carried out with 211 workers of both genders, aged between 30 and 64 years, working on the health campus of a public university in the state of Minas Gerais, Brazil. Night-shift work was defined as a work shift between 7 pm and 7 am, and high cardiovascular risk was calcu...

It has been suggested that shift work, night work in particular, affects worker's psychophysical health. However, the effects of night work on the health of pregnant women are not physiologically well elucidated. The effects of night work on the biological function of pregnant women were studied in the present study. Three pregnant and six non-pregnant nurses that engaged in fast-rotating shift...

This study examined the impact of eating during simulated night shift on performance and subjective complaints. Subjects were randomized to eating at night (n=5; 23.2 ± 5.5 y) or not eating at night (n=5; 26.2 ± 6.4 y). All participants were given one sleep opportunity of 8 h (22:00 h-06:00 h) before transitioning to the night shift protocol. During the four days of simulated night shift partic...

This study examined the impact of eating during simulated night shift on performance and subjective complaints. Subjects were randomized to eating at night (n=5; 23.2 ± 5.5 y) or not eating at night (n=5; 26.2 ± 6.4 y). All participants were given one sleep opportunity of 8 h (22:00 h-06:00 h) before transitioning to the night shift protocol. During the four days of simulated night shift partic...

OBJECTIVE To evaluate the attention, learning and memory related cognitive functions after 12-hour day versus night shift-work in anaesthesia residents. METHOD Fifteen residents working on the day shift and 18 working on the night shift volunteered. All were interviewed with the Rey Auditory Verbal Learning Test (AVLT), Visual Aural Digit Span Test (VADST), and State Trait Anxiety Inventory (...