BACKGROUND: The decisive importance of the sympathetic and parasympathetic nervous system in maintaining vegetative homeostasis requires the determination of sensitive non-invasive parameters of multidimensional outpatient monitoring of cardiorespiratory adaptation under various physiological and clinical conditions, taking into account the function of external respiration (FER), compound body composition and heart rate variability (HRV).AIM: To identify concomitant changes in HRV, HR and compound body composition in young people as markers of cardiorespiratory adaptation and rehabilitation.MATERIALS AND METHODS: On the basis of the Kuban State Medical University, a single-centre, interventional, cross-sectional, single-sample, comparative, uncontrolled study of a general group of young people in which respiratory parameters and parameters of the compound body composition were determined. Some individuals in this group additionally underwent Holter monitoring of the electrocardiogram (ECG) at short intervals.RESULTS: In young people, a change in the compound body composition with an increase in total fat mass, visceral and body fat is associated with a decrease in respiratory function (a decrease in the Tiffno index, a decrease in the maximum middle-expiratory flow — MMEF), manifested by a decrease in HRV (according to the TI indicator), the absence of an increase in the autonomic regulation circuit (according to SDNN indicator), a decrease in parasympathetic activity (in terms of rMSSD) and the absence of sympathetic activation (in terms of SDANN). Positive shifts in the form of an increase in trunk muscles, the total amount of water and a decrease in the total fat mass are accompanied by an increase in lung capacity, forced expiratory volume in the first second and a change in HRV with sympathetic (in terms of LF / HF, SDANN) and parasympathetic activation (in terms of rMSSD), an increase in HRV (in terms of TI) and an increase in the autonomic regulation circuit of the vegetative nervous system (in terms of SDNN).CONCLUSION: Accurate and rapid diagnostics of vegetative homeostasis requires a comprehensive correlative analysis of the parameters characterizing HRV in short recordings, the compound composition of the human body and respiratory function.

The review highlights the prevalence, pathogenesis and clinical manifestations of bronchial asthma (BA), comorbid with gastroesophageal reflux disease (GERD). Difficulties in diagnosing triggers of extraesophageal symptoms were noted. Based on a large number of clinical studies, the review assesses the possibilities of minimally invasive methods for detecting biomarkers of gastroesophageal  reflux (GER) and duodenogastroesophageal reflux (DGER) in the oral fluid. With syntropy of GERD and BA, a significant role and relationship between the parameters of respiratory oxidative inflammation and impaired functions of external respiration was noted. To confirm the reflux origin of extraesophageal respiratory symptoms, it is important to use minimally invasive methods for detecting bilirubin and pepsin in the oral fluid, and to assess the activity of respiratory stress, the determination of its substrates in the blood. Further studies aimed at determining the normative concentrations of DGER substrates in the oral fluid and markers of oxidative respiratory inflammation in the blood will help improve the diagnosis and treatment of BA and GERD syntropy in outpatient practice.