Characterization of the interrelationship between the autonomic nervous system and the cardiovascular system in patients with apnea and hypopnea syndrome, as a support for diagnosis and follow-up in pre- and post-treatment stages

It is estimated that sleep apnea and hypopnea syndrome (OSAHS) affects between 4 and 6% of the Colombian population. This consists of alterations that produce sudden interruptions in breathing during a person's sleep, whose chronic consequences at a physiological and metabolic level significantly deteriorate the quality of life of those who suffer from this disease. In this sense, the activities controlled by the autonomic nervous system (ANS) are altered, including the cardiovascular system (SCV). In turn, OSAHS leads to irregularities in the interaction and interconnection between these two systems, affecting the continuous bidirectional influence that one system has on the other. Several research groups have explored tools based on digital processing of biomedical signals on polysomnography data to characterize and quantify the effects of OSAHS on the physiological network made up of the ANS and the SCV. Specifically, these analyzes have focused on the information contained in electrocardiography (ECG) and electroencephalography (EEG) signals, either on the separate signals or by analyzing the connectivity between each of them. Regarding this last approach, it is still necessary to explore the usefulness of tools that quantify the connectivity between SNA and SCV in the presence of OSAHS, since the studies presented have been developed with linear tools or in populations of subjects without this disease. Therefore, the effect on the dynamics of the interaction between SNA and SCV as a result of any treatment to counteract OSAHS, be it continuous positive air pressure (CPAP) in adults or tonsillectomy in children, is not fully known. Knowing these characteristics could contribute and complement the diagnosis of this disease and improves the precision in its follow-up.