Influence of Night Shift Work on Psychologic State and Cardiovascular and Neuroendocrine Responses in Healthy Nurses.

Abstract

Night shift work has often been associated with increasing degree and frequency of various psychologic complaints. The study examined whether psychologic states after night work are related to adaptive alterations of the cardiovascular and neuroendocrine systems. We studied 18 healthy nurses (age 29+/-2 years) engaged in a modified rapid shift rotation system (day work, 8:15-17:15; evening work, 16:00-22:00; night work, 21:30-8:30). Blood pressure, heart rate, RR interval variability (L/H and HF power spectrum for sympathetic and vagal activities), and physical activity were measured using a multibiomedical recorder for 24 h from the start of work during the night and day shifts. Plasma ACTH and cortisol concentrations were measured at the end of each shift and at 8:30 AM on a day of rest. Each subject's psychologic state was assessed using a validated questionnaire. Among the parameters measured, scores for confusion, depression, anger-hostility, fatigue and tension-anxiety were highest, and scores for vigor lowest, after a night shift. Systolic blood pressure and heart rate during work were lower during night shift than during day shift (119+/-2 vs. 123+/-1 mmHg, p<0.05 and 75+/-1 vs. 84+/-2 bpm, p<0.001, respectively). Both parameters were lower still (p<0.005 and p<0.05) when measured outside of the hospital under waking conditions following a night shift than following a day shift, even though the levels of physical activity were similar. The HF power spectrum of RR interval variability was greater not only during work (24.2+/-2.1 vs. 18.5+/-1.8 ms, p<0.005) but also during the awake period (29.1+/-2.5 vs. 24.4+/-2.6 ms, p<0.005) after the night shift compared with the day shift. Plasma ACTH and cortisol concentrations were lower after night work than in the day of rest (7.3+/-1.2 vs. 11.5+/-2.3 pg/ml, p<0.1 and 11.1+/-1.1 vs. 14.4+/-1.1 mg/dl, p< 0.05). Systolic and diastolic blood pressures during night shift work and the subsequent awake period correlated positively with scores for vigor and negatively with scores for confusion (p<0.05). Plasma ACTH and cortisol concentrations did not correlate with any psychologic scores. We conclude that psychologic disturbances after night work were associated with altered cardiovascular and endocrine responses in healthy nurses. Some of the psychologic complaints may be attributable to lower waking blood pressure.

Health Effects Associated With Shift Work in 12-Hour Shift Schedule Among Iranian Petrochemical Employees

“…Whereas there is evidence to suggest that shift work is associated with an increasing degree and frequency of psychological complaints [22,23,24], this study found no significant association between shift work and psychological problems. Regression analysis indicated that weekly working hours, type of employment and job unit were the only retained factors in the model.…”

Path Analysis of Depression and Quality Of Life Among Nurses

“…A lot of research have shown the correlation between depression and shifts, especially night shifts (6,22,23). As shown by Ruggiero et al, night shifts can develop or even exacerbate sleep disorder, and on the other hand, there is a relationship between sleep disorder, affective disorder, and depression (23), so a direct relation exists between increased working hours and depression, which is consistent with our findings (24,25).…”

Associations of Long-term Shift Work with Waking Salivary Cortisol Concentration and Patterns among Police Officers

“…However, few studies have investigated the influence of long-term (or extended) shift work on the HPA axis and the awakening cortisol. Also, the findings from previous studies on the association between shiftwork and awakening cortisol have been inconsistent [19][20][21][22][23][24][25][26][27][28] ; both, high and low waking cortisol levels have been reported among shift workers.…”