[Disturbances of Autonomic Regulation of Cardiovascular System at Different Working Regimes with Night Shifts].

Aim        To study temporal and spectral characteristics of heart rhythm variability (HRV) in night shift workers.Materials and methods       Along with traditional risk factors, conditions of labor contribute to development of cardiovascular morbidity, including night shift work, which can be associated with disorders of the autonomic regulation detected by analysis of HRV. This study included 100 healthy men. 74 of them were engaged in shift work, including 53 men with rotating shift work, 21 men with fixed night shifts, and 26 men with day-time work. HRV was analyzed by data of 5-min electrocardiogram recording (background recording and orthostatic test).Results   Night-shift workers had decreases in total power of regulation (ТР, SDNN) and in the parasympathetic branch (HF, pNN50). Rotating night-shift workers displayed significant decreases in SDNN and pNN50 and pronounced changes in the VLF / LF / HF ratio in the orthostatic test.Conclusion            In work with night shifts, the type of autonomic regulation differs from the "standard" functioning of the autonomic nervous system (ANS). This study showed different effects of night work regimens on HRV indexes. With the rotating shift work, the ANS dysregulation was more profound and was evident by a significant decrease in the ANS total tone and parasympathetic activity (SDNN, pNN50) compared to night shifts with fixed working hours. The excessive weakening of the parasympathetic component in the passive orthostatic test can be considered as an early marker for ANS maladaptation.

[Peculiarity of autonomic functions regulation remodeling in human adaptation to extreme conditions in labor activities].

In modem society, professional activity in conditions of extreme factors occupies a growing place. Of particular note is the work related to night shifts involving up to 20% of the population. In some cases, this work may lead to a breach of the adaptation processes of the body and increase the risk of diseases. The necessity to search criteria of dysregulation changes in the human body during adaptation to extreme conditions in labor activities is the actual problem from the standpoint of preventive health care of the working population health and providing safety in professional activities conditions. In our work, we attempted to identify early signs of autonomic function's dysregulation by analyzing the heart rhythm variability in locomotive operators and doctors on duty. It was revealed that these groups of people with different levels of intensity of professional activities may be the model for observation of the stages of dysregulation process. It is also shown that the earliest markers of autonomic regulation remodeling are indicators of the spectral analysis of heart rhythm variability, reflecting the activity of the total power regulation (TP) and parasympathetic part (HF).

[Work with night shift as a factor dysregulation of autonomic nervous system of locomotive drivers].

Work with night shift is an obligate necessity of modem industrial urban society. In developed countries in the work on the night shift use up to 20%. These categories of workers are definitely the locomotive drivers. The consequence of a regular work with night shifts is a violation of human circadian rhythms, which, through dysregulation of the autonomic nervous system, is reflected in a greater risk of disease and transport accidents. The need to find ways and criteria of preventive monitoring dysregulatory changes in the human body is an urgent and challenging issue in terms of the health of the working population, disease prevention, and transportation security.