Variability in Perception of Dyspnea in the Context of Additional Respiratory Resistance: Cross-Sectional Observational Exploratory Study

Abstract

Background. In various situations healthy people may experience breathlessness caused by high altitude, breath-holding, anxiety or panic driven by stressful events, and, very often by physical activity. However, variability in perception of dyspnea in healthy individuals is yet to be explored. The present study analyzes the variability of dyspnea perception in healthy people in the context of additional respiratory resistance.Objective — to assess the variability in perception of dyspnea in healthy individuals against a step-up increase in additional respiratory resistance, and to evaluate the relationship between dyspnea perception and physical activity levels.Methods. A cross-sectional observational exploratory study involved healthy individuals aged 19–25. The study was conducted at the Department of Pathophysiology, Ryazan State Medical University named after acad. I.P. Pavlov (Russia), in the period from November 2018 to June 2019. A total number of individuals under study comprised 42. Study participants were subjected to additional respiratory resistance, when dyspnea perception was estimated using a modified Borg scale. Then all participants were divided into three groups according to the tertiles in their perception: slight perception (Borg score < 2; n = 13), moderate perception (Borg score 2–5; n = 19) and high perception (Borg score > 5, n = 13). The study involved determination of body mass index, maximal airway pressure, pulmonary function, physical activity by means of IPAQ (International Physical Activity Questionnaire) and 6MWT (6 Minute Walking Test). Data analysis was performed using IBM SPSS Statistics 17.0 (USA).Results. The study included 42 healthy individuals. The level of dyspnea perception was determined as slight (low), moderate (medium) and high in 13, 19 and 10 participants, respectively. Perceived level of breathlessness did not significantly correlate with age, gender, body mass index, physical activity, maximum airway pressure or pulmonary function test results.Conclusion. Perceived dyspnea caused by a step-up increase in additional respiratory resistance varied significantly. The perception of dyspnea was determined as slight in 31% of participants, moderate in 45% and high in 24%. The authors did not reveal a correlation between dyspnea perception and physical activity level (via IPAQ or 6 Minute Walking Test).