title: The effect of obesity on spirometry tests among healthy non-smoking adults.
abstract: BACKGROUND
  The effects of obesity on pulmonary functions have not been addressed previously among Saudi population. We aim to study the effects of obesity on spirometry tests among healthy non-smoking adults.
  
  
  METHODS
  A cross sectional study conducted among volunteers healthy non-smoking adults Subjects. We divided the subjects into two groups according to their BMI. The first group consisted of non-obese subjects with BMI of 18 to 24.9 kg/m2 and the second group consisted of obese subjects with BMI of 30 kg/m2 and above. Subjects underwent spirometry tests according to American thoracic society standards with measurement of the following values: the forced vital capacity (FVC), forced expiratory volume in one second (FEV1), peak expiratory flow rate (PEF) and forced mid-expiratory flow (FEF25-75).
  
  
  RESULTS
  The total subjects were 294 with a mean age of 32 years. There were 178 males and 116 females subjects. We found no significant differences in FEV1 (p value = 0.686), FVC (p value = 0.733), FEV1/FVC Ratio (p value = 0.197) and FEF25-75 (p value = 0.693) between the obese and non-obese subjects. However, there was significantly difference in PEF between the two groups (p value < 0.020).
  
  
  CONCLUSIONS
  Obesity does not have effect on the spirometry tests (except PEF) among health non-smoking adults. We recommend searching for alternative diagnosis in case of findings abnormal spirometry tests results among obese subjects.
authors.affiliation: Department of Medicine, College of Medicine, King Saud bin Abdulaziz University for Health Sciences, Riyadh, P.O. Box 90068 11321, Saudi Arabia. alanezi@hotmail.com
authors.forename: Mohammed
authors.initials: M
authors.lastname: Al Ghobain
mesh_terms: D000328:Adult; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005260:Female; D005541:Forced Expiratory Volume; D006801:Humans; D008168:Lung / Q000502:physiology*; D008297:Male; D009765:Obesity / Q000503:physiopathology*; D010366:Peak Expiratory Flow Rate; D012529:Saudi Arabia; D013147:Spirometry; D014797:Vital Capacity; D055815:Young Adult