Poincaré maps are a time series analysis technique, that consists in a scattered plot that allows the visualization of the dynamics in a time series. This study aims to visualize and characterize the behavior of complex systems (human body) in disease (COVID-19 disease with lung involvement), according to prognosis outcome, stratified by two comparable groups. The potential use of our work lies in its possible application for identifying biomarkers of physiological health and predictive biomarkers in the prognosis against COVID-19 by changes in system dynamics. Results show that certain variables such as Diastolic blood pressure, PaO2/FiO2, average epicardial fat, direct bilirubin, and Triglyceride-Glucose Ratio/BMI can be inferred as important predictive markers of worse prognosis against COVID-19, with dynamic becoming deterministic.

Background/Objectives: Wearable devices offer a scalable approach to repeated cardiovascular assessment through ambulatory spot measurements and have demonstrated adequate performance in measuring heart rate (HR). However, their reliability for blood pressure (BP) assessment remains uncertain. This study aimed to evaluate BP and HR measurements obtained with the HUAWEI WATCH D2 smartwatch by comparison with standard reference devices under controlled postural conditions. Methods: A total of 30 participants (15 women and 15 men; age range, 21–88 years) were enrolled. One participant could not undergo smartwatch measurement because of wrist-size limitations, and measurement acquisition failed in another participant. Consequently, paired measurements obtained in the seated and upright positions were analyzed for 28 participants. Smartwatch-derived systolic BP (SBP), diastolic BP (DBP), and HR were compared with a digital sphygmomanometer, an analog sphygmomanometer, and a digital pulse oximeter. Agreement was assessed using percentage error and Bland–Altman analysis, complemented by linear regression to evaluate proportional bias. Results: In the seated position, the smartwatch showed agreement with percentage errors below 4% for SBP and DBP, with concordance coefficients indicating good agreement. In the upright position, accuracy decreased, with percentage errors up to 14%, increased variability, wider limits of agreement, and the presence of systematic and proportional discrepancies. Measurement performance was influenced by device placement, and isolated failures highlighted sensitivity to anatomical and technical factors. Conclusions: Smartwatch-based BP monitoring is feasible under controlled conditions but remains dependent on posture and measurement conditions. These findings support the use of wearable devices for scheduled spot-check cardiovascular assessment under controlled conditions and underscore the need for standardized measurement protocols before their implementation in ambulatory or long-term monitoring applications.

The human body is a complex system where patterns emerge as a result of the interactions between multiple phys-iological systems. These interactions are affected by illnesses such as COVID-19. A potential treatment of COVID-19 patients is intramuscular administration of polymerized type I collagen (PTIC). In this work we evaluate the effect of the intramuscular administration of PTIC and placebo in the physiological network of patients with COVID-19. Furthermore, we investigated sex differences in the correlation between baseline and time evolution of experimental test.