Correlation of Obesity and Peak Expiratory Flow Rate in Young Adult Females

Abstract

Background and Purpose: Pulmonary functions are determined by respiratory muscle strength, compliance of the thoracic cavity, airway resistance and elastic recoil of the lungs. Peak Expiratory Flow Rate (PEFR) is the maximum rate of airflow achieved during a forced expiration after maximal inspiration. Obesity can affect diaphragm, thoracic and abdominal muscles. Increased respiratory effort and impairment of gas transport system can result in altered pulmonary functions. In India, obesity has reached epidemic proportions in the 21st century, with 5% of the country’s population being affected with morbid obesity. The prevalence of obesity among Indian women has increased from 10.6% to 12.6%, i.e. an increase by 24.52% in a seven year period. Markers of obesity such as Body Mass Index (BMI) and Waist Hip Ratio (WHR) may be correlated to PEFR. Thus, the aim of this study is to correlate the effects of obesity on pulmonary functions. Objectives: To assess the effect of BMI on Peak Expiratory Flow Rate (PEFR) in young adult females. To assess the effect of WHR on Peak Expiratory Flow Rate (PEFR) in young adult females.To compare BMI and WHR as a measure of obesity in terms of correlation with PEFR Design: Correlational study Methods: 45 subjects between the age group of 20 to 40 years were recruited for the study. Written informed consent and institutional ethical clearance were obtained. Anthropometric measurements were obtained using the Quetelet index for BMI and WHR was derived by dividing the waist circumference from the hip circumference. PEFR was obtained using the Wright’s portable peak flow meter in standing position. Results: Data has been derived using SPSS 16.0 software. Pearson’s correlation coefficient test was used to find the correlation between BMI and PEFR and WHR and PEFR. Correlation coefficient for BMI and PEFR was r = -0.48 and is statistically significant (p < 0.001). The correlation coefficient between WHR and PEFR was r = -0.074 which is not statistically significant (p = 0.31). Conclusion: PEFR was found to be significantly influenced by BMI, irrespective of the type of body fat deposition. Thus, the study concluded that there is a reduction in the lung volumes as the BMI increased.