Analysis of Cardiopulmonary Characteristics in Young Patients Depending on Smoking Status
Smoking is an important medical and social problem leading to serious economic losses throughout the world. There is no doubt that smoking is a risk factor for numerous pathological conditions and has a significant impact on the cardiovascular and pulmonary systems of patients including young people. The aim of this study was to assess cardiopulmonary characteristics in young patients depending on smoking status. In 2021-2022 55 young patients from 18 to 44 years old (63.6% of women) were examined, 61.8% of them non-smokers and 38.2% smokers. The median age of the participants was 22.0 years (Q1-Q3 21.0-34.0). All participants underwent cardiopulmonary exercise testing using CARDIOVIT CS-200 Ergo-Spiro machine (Schiller, Switzerland). Statistical analysis was carried out using the StatTech v.2.6.7 software (Stattech LLC, Russia). The mean value of maximum oxygen consumption (VO2 max) was 1.792 ± 0.596 L/min (95% confidence interval (CI) 1.631-1.954) or 74.1 ± 17.3% (95% CI 69.4-78.8) of the predicted values, which is below normal values (>84%) and corresponds to a mild degree of physical performance decrease. The median value of ventilatory anaerobic threshold (VAT) was 41% (Q1-Q3 35-52), which corresponds to the lower limit of the normal value (>40%). Maximum heart rate was 90% of the predicted value, which is the cutoff value for the normal range. The mean value of oxygen pulse (O2-pulse) was generally outside the normal range and amounted to 71.6 ± 15.4% with the norm of >80%. The heart rate reserve was 20 bpm exceeding the norm (<15 bpm). When comparing the indicators during exercise between the groups of smokers and non-smokers, it was found that smokers were characterized by higher values of VO2 max suggesting the presence of hypoxia and higher values of O2-pulse (10.9 mL/beat vs 8.8 mL/beat, p = 0.044), indicating a less efficient functioning of the autonomic nervous system in smokers. Cardiopulmonary exercise testing allows to objectively measure the level of working capacity and the degree of functional disorders associated with its decrease in patients without obvious signs of cardiovascular and pulmonary disorders.