Effects of progressive increase in body weight on lung function in six groups of body mass index.
OBJECTIVE
To evaluate the effects of the progressive increase in body weight on lung function by oxygen peripheral saturation, spirometry and maximal respiratory pressures in different degrees of obesity.


METHODS
Cross-sectional study including 140 patients in clinical and surgical evaluation for obesity treatment. The selected patients were divided into six groups of body mass index (BMI), including a control group of non-obese and a subdivision for the morbidly obese into three subgroups.


RESULTS
Significant differences were demonstrated between the groups regarding oxygen peripheral saturation (SpO2) (p < 0.001), forced vital capacity (FVC) (p < 0.002, p < 0.02) and forced expiratory volume in one second (FEV1) (p < 0.001, p < 0.03) in relative and absolute values, respectively. Group VI (BMI > 50.9 kg/m²) showed significant differences (SpO2, FVC and FEV1) when compared with the other groups (except group V) and group V (BMI > 45 to 49.9 kg/m²) with the group control. The other variables (FEV1/FVC ratio, forced expiratory flow 25-75 [FEF25-75] and maximal respiratory pressure) did not show any statistical differences.


CONCLUSIONS
Lung function is influenced by the progressive increase in BMI, with changes in lung function better demonstrated when BMI > 45 kg/m²; these changes are more evident when BMI > 50.9 kg/m².
Universidade Federal de Sergipe, Aracaju, SE, Brazil.
Saulo Maia
SM
D'Ávila Melo
Valdinaldo Aragão de
VA
Melo
Raimundo Sotero de
RS
Menezes Filho
Fábio Almeida
FA
Santos
D000293:Adolescent; D000328:Adult; D015992:Body Mass Index; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008168:Lung / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000378:metabolism / Q000503:physiopathology*; D010101:Oxygen Consumption; D012129:Respiratory Function Tests; D013147:Spirometry; D014797:Vital Capacity; D015430:Weight Gain; D055815:Young Adult