A comparative study on the effect of increased body mass index on pulmonary function and respiratory muscle strength in young adults

Abstract

Background: Obesity decreases the working ability of the persons and leads to a number of morbid conditions. Respiratory muscle strength assessment in obese individual helps to understand the modifications that the body does in turn to the ever-increasing oxygen intake and carbon dioxide output. Aim and Objectives: The aim and objective of this study is to determine the association between the increasing body mass index and the respiratory muscle strength in young adults using spirometry and estimation of the maximum inspiratory and maximum expiratory pressures. Materials and Methods: The Institutional Ethics Committee clearance was obtained and written informed consent form was obtained from all the research participants. Age-matched obese (n = 32) and non-obese (n = 32) individuals were recruited, and their anthropometric data were recorded. Spirometry was done using RMS Helios 407 PC Based Spirometer. Maximum inspiratory and expiratory pressures were measured using a custom-built standardized equipment. The American Thoracic Society/European Respiratory Society guidelines were followed in the conduct and calibration of the machines used. Pearson’s correlation and student t-test were done for the parameters of interest using GraphPad Prism v5.0 software for statistical analysis. Significance was set at P < 0.05. Results: A significant change in the parameters such as maximum voluntary ventilation and maneuver tidal volume was found. Non-significant changes in other spirometry parameters were seen between the obese and the non-obese individuals. Conclusion: Our results were in contradictory to those findings wherein there was a decrement in the spirometric and respiratory muscle strengths; however, there was also literature that is concurrent to our findings. The significant increase in the respiratory muscle strength in obese individuals might be a compensatory effect to the exertion to be done against the increased lung function required in obese individuals with an equivalent effort to that of non-obese normal individuals.