title: The effect of massive weight loss on pulmonary function of morbid obese patients.
abstract: OBJECTIVE
  To test if morbid obesity causes pulmonary function changes and if massive weight loss have effect on pulmonary function (especially in subjects with BMI>or=60 kg/m(2)).
  
  
  METHODS
  Thirty-nine morbid obese subjects before and after massive weight loss.
  
  
  RESULTS
  Patients had baseline BMI>or=40 kg/m(2), pulmonary function test (PFT) before and after surgery for gastric volume reduction and massive weight loss, and presented no complaints unrelated to obesity. Based on initial BMI, the patients were divided in groups A (BMI 40-59.9 kg/m(2)) and B (BMI>or=60 kg/m(2)). Initially, group A (n=28) had normal PFT, however group B (n=11) presented FVC and FEV(1) measurements in the lowest limit of normality (with normal FEV(1)/FVC), significantly different from group A. After massive weight loss, the group B compared to A had a significant improvement in FVC (23.7% vs. 9.7%, P=0.012) and FEV(1) (25.6% vs. 9.1%, P=0.006); thus the initial difference in FVC and FEV(1) between groups no longer existed after weight loss.
  
  
  CONCLUSIONS
  These results point out that the severe morbid obesity (BMI>or=60 kg/m(2)) may lead to pulmonary function impairment and presents more prominent pulmonary function gain after massive weight reduction. The possible clinical implications of these results are that PFT abnormalities in subjects with BMI<60 kg/m(2) should probably be interpreted as consequence of intrinsic respiratory disease and that severe morbid obese patients may be encouraged to lose weight to improve their pulmonary function, especially those with concomitant pulmonary disorders.
authors.affiliation: Pulmonary Division, University of São Paulo Medical School, São Paulo, SP, Brazil. alfredonicodemos@hotmail.com
authors.forename: Alfredo N C
authors.initials: AN
authors.lastname: Santana
authors.forename: R
authors.initials: R
authors.lastname: Souza
authors.forename: A P
authors.initials: AP
authors.lastname: Martins
authors.forename: F
authors.initials: F
authors.lastname: Macedo
authors.forename: A
authors.initials: A
authors.lastname: Rascovski
authors.forename: J M
authors.initials: JM
authors.lastname: Salge
mesh_terms: D000328:Adult; D015992:Body Mass Index; D005260:Female; D005541:Forced Expiratory Volume; D015391:Gastroplasty; D006801:Humans; D016014:Linear Models; D008168:Lung / Q000503:physiopathology*; D008297:Male; D009767:Obesity, Morbid / Q000503:physiopathology* / Q000601:surgery; D014797:Vital Capacity; D015431:Weight Loss / Q000502:physiology*