A comparison of pulmonary function and respiratory muscle strength in overweight, class I and class II obesity

Abstract

Obesity is an important problem that affected on respiratory system. The purpose of this study was to compare the spirometric pulmonary function test and respiratory muscle strength among the groups of people with of overweight, class I and II obesity. One hundred and twenty volunteers were divided into 3 groups of overweight, class I obesity, and class II obesity, where each of the groups consisted of 20 males and 20 females. Age and height were not statistically different in among the groups, but weight and body mass index were statistically different in all groups (P < 0.05). All subjects underwent spirometry test, maximal inspiratory pressure, maximal expiratory pressure, where the highest value for each parameter was chosen for analysis. Results showed that class II obesity group achieved the least readings of FVC, FEV₁, FEV₁/ FVC, PEF, and FEF_25-70% compare with those of overweight and class I obesity (P < 0.05). Respiratory muscle strength in obesity class 2 was lower than overweight and class I obesity (PI max; 79.15 ± 21.04, 69.68 ± 15.12 and 67.28 ± 11.81 cmH₂O) (PE max; 74.03 ± 11.48, 57.95 ± 12.66 and 54.55 ± 17.06 cmH₂O) (P < 0.05). In conclusion, the pulmonary function test and respiratory muscle strength in class II obesity was lower than overweight and class I obesity. Also, the people with high body mass index may effect to decrease of pulmonary function test and respiratory muscle strength.

Keywords:  Obesity,  Pulmonary function,  Respiratory muscle strength