Influence of violations of autonomic regulation on the development of occupational polyneuropathy of the upper extremities in Kuzbass miners
Introduction. Active coal mining in Kuzbass, with its unfavorable climatic and environmental conditions, necessitates the study of occupational diseases of workers in this industry. One of the most common occupationally caused diseases of miners is polyneuropathy of the upper extremities. The aim of the study is to assess the effect of autonomic disorders on the course of occupational upper limb polyneuropathy in workers of the Kuzbass coal industry using various methods of analyzing heart rate variability. Materials and methods. 52 employees of coal enterprises aged from 43 to 64 years with the established diagnosis of “polyneuropathy of the upper extremities” were examined. The control group consisted of 16 healthy volunteers of the same age, engaged mainly in mental or light physical labor. Electroneuromyography was performed to assess the degree of damage to peripheral nerve fibers. Spectral and nonlinear parameters of heart rate variability were used to determine the state of autonomic regulation. The Mann-Whitney criterion was used to assess the statistical significance of differences between the study groups. Results. 3 groups of patients with polyneuropathy were identified according to the severity of violations of impulse conduction in the peripheral nerves. In subjects with mild, initial disturbances of pulse conduction (n=8, 15.4%), a decrease in parasympathetic influence is determined, which is manifested by a statistically significant decrease in the power of high- frequency oscillations of the heart rate variability spectrum. With moderate signs of polyneuropathy (28 cases, 53.9%), there is a shift in the autonomic balance towards sympathetic activation; a statistically significant increase in very low-frequency fluctuations in heart rate variability indicates an increase in the influence of suprasegmental autonomic centers. In subjects with gross violations of the peripheral nerve impulses (n=16, 30.7%), there is a decrease in the power of oscillations in all frequency ranges of heart rate variability. Conclusions. The obtained data confirm the influence of autonomic regulation on the course of occupational polyneuropathy.