АВТОНОМНА НЕРВОВА РЕГУЛЯЦІЯ У ДІВЧАТ-ПІДЛІТКІВ З НАБУТИМИ ЗОРОВИМИ ДИСФУНКЦІЯМИ

Abstract

Introduction. 12-15 years old is a critical period for the manifestation of autonomic nervous dysfunction against the background of morphological and functional heterochrony of various organs and systems. The presence of visual dysfunctions is one of the risk factors for the development of autonomous nervous imbalances. There is no consensus on the autonomous nervous regulation in people with visual dysfunctions. Purpose of this article is to find out the features of autonomous nervous regulation in teenage girls with obtained visual dysfunctions. Methods. The study involved 12-15 years old girls with different vision function: 20 girls with normal vision and 19 girls with obtained bilateral vision dysfunctions (the corrected visual acuity left was 0.65 ± 0.07). The studies were conducted in a darkened room in a sitting position with closed eyes. ECG registration was carried out within 2.5 minutes. The comparison of the HRV indexes in girls with different vision functions was performed on the basis of the Wilcoxon-Mann-Whitney criteria and Fisher's angle transform criterion. The factor model of HRV was built on the basis of a correlation matrix of 29 HRV indexes (spectral, autocorrelation, statistical and R.M. Baevsky’s indexes) and Varimax rotation. Results. Teenage girls were characterized by lower (by 42.0%, P ≤ 0.05) values of VLFt compared to control, indicating a shortening period of the reflex response of the cardiovascular subcortical center. The normal heart rate prevailed in the control group (95.0%) while the bradycardia prevailed in girls with visual dysfunctions (55.6%). In control group the factor structure of HRV was formed by three factors: factor 1 (general autonomous nervous system tone; SDNN, TP, VLF, LF, HF, ΔX, CVr were the most contributing indexes are factors) – 43.7%, factor 2 (centralization of management; AMo, IVB, IA, IARP, ART, SI, VIR ) –23.7%, and factor 3 (sympathy-vagal balance) – 16.3%. In girls with visual dysfunctions the factor structure of HRV was formed by two factors: factor 3 (59.3%) and factor 1 (18.1%). At the same time the Factor 1 had negative correlation with HRV indexes instead of positive correlation in control group. Originality . For the first time, a comparative analysis of the HRV indexes and its factor structure in teenage girls with different visual functions was conducted. Conclusion. Teenage girls with obtained bilateral vision dysfunctions are characterized by different mechanisms of autonomous nervous regulation of heart chronotropic function. The tendency toward bradycardia against the background of intensifying of sympathetic nervous system activity is an indicator of chronic psycho-emotional stress in teenage girls with obtained visual dysfunctions.