Regional Specificity of Neurovegetative Regulation on the Example of the North-East of Russia and the North Caucasus

BACKGROUND: Heart rate variability (HRV) is a highly informative marker of neurovegetative regulation of cardiovascular activity, as well as a method for quantitatively assessing its physiological changes, allowing for the analysis of the specifics of neurovegetative regulation, taking into account the influence of climatic and geographic factors of different regions of residence. AIM: The study of regional characteristics, as well as differences in the autonomic control of the circulatory system based on heart rate variability indicators in individuals living in different natural and climatic zones such as the North-East (Magadan) and the North Caucasus (Vladikavkaz), which differ in both climatic conditions and relief (lowland and low mountain). METHODS: The indices of the autonomic regulation of the heart were assessed in the time and frequency domains in 89 young men, 41 of whom were born in the North-Eastern region (Magadan) (mean age 19.8±0.5 years) and 48 young men were born in the North Caucasus (Vladikavkaz) with an average age of 20.8±0.8 years. All study participants underwent an analysis of the key parameters of the HRV at rest (sitting position) using the «Varicard» hardware and software complex. The type of autonomic regulation was determined based on the variation range (MxDMn) and stress index (SI), assessed in a state of rest. RESULTS: The results obtained allowed us to establish that living in low-altitude conditions leads to a decrease in vegetative functions, which was associated with a decrease in the activity of the parasympathetic link of the autonomic nervous system, shifting the sympathovagal balance to a relative state of sympathetic activity. In the natives of the North-Eastern region, in lowland conditions, most of the heart rate variability parameters corresponded to the optimal physiological ranges with a shift of a number of parameters to the area of parasympathetic activity. CONCLUSION: The conducted studies demonstrate that the heart rate variability parameters reflect the specificity of adaptive restructuring of physiological systems, forming ranges of the functional norm characteristic of each natural and climatic zone. These indicators can serve as objective markers of the body's response to extreme environmental factors characteristic of various regions of the Russian Federation. Our study complements the results of scientific research on the shift of the neurovegetative regulation vector to the area of sympathetic activation of the circulatory system as a component of adaptation to combined mountain climatic factors (North Caucasus) and, conversely, in the formation of compensatory mechanisms of vegetative regulation in conditions of extreme climatic factors of the northern territories, manifested in increased tonic activity of the vagus nerve.