Abstract
The purpose of the investigation was to study group dynamics of seasonal changes in the autonomic nervous and cardiovascular functions in apparently healthy men who occupationally deal with frequent stressful situations (field personnel and firefighters of the Almaty Emergency Management Department (EMD), Emergency Ministry of the Republic of Kazakhstan (EM RK). The investigation was conducted according to the program of parallel medical and environmental investigations within the framework of the Mars-500 project in the city of Almaty, based on the support from the Kazakh National Medical University with respect to terminology based on using the prenosological approach which allows one to assess states in between the norm and pathology. Results of the year-long investigation demonstrated seasonal variations in the functional state of body with identification of groups up to prenosological ones, which could be associated with specific occupational factors and arduous duty, as it follows from the Almaty EMD operational summary (autonomic balance shifting toward prevalence of the sympathetic control during spring and summer arduous duties, and toward the parasympathetic control under quiet duty conditions during wintertime). These observations testify to the importance of dynamic health monitoring concerning apparently healthy people who are occupationally exposed to chronic psycho-emotional strain for prenosological diagnosis and timely preventive intervention.