title: Association of gastroesophageal reflux disease symptoms with stable chronic obstructive pulmonary disease.
abstract: BACKGROUND
  Patients with various chronic respiratory diseases have a higher incidence of gastroesophageal reflux disease (GERD)-related symptoms, but the mechanisms of the relationship between GERD symptoms and chronic obstructive pulmonary disease (COPD) remain unclear. The aim of the present study was to explore the association of GERD symptoms with impaired pulmonary function and other factors in patients with COPD.
  
  
  METHODS
  Patients with clinically stable COPD were consecutively recruited, and a pulmonary function test, visual analogue scale (VAS), and Reflux Diagnostic Questionnaire (RDQ) were administered. The patients were categorized into GERD-positive and GERD-negative groups according to the RDQ. Univariate and multivariate analyses were performed to evaluate the factors associated with the incidence of GERD symptoms in COPD.
  
  
  RESULTS
  A total of 1,486 patients with COPD were enrolled. There was no difference in age, gender proportion, body mass index, tobacco exposure, and the use of respiratory medications between the GERD-positive and GERD-negative groups. The respiratory pattern, the values of forced expiratory volume in 1 s, inspiratory capacity (IC), and residual volume, and VAS scores were significantly different between the groups (all P<0.05). Multivariate logistic regression analysis revealed that the decreased IC (odds ratio (OR) =1.56; 95% CI=1.32-2.27; P<0.001) and increased VAS scores (OR=1.38; 95% CI=1.19-1.68; P=0.011) were independent risk factors of GERD symptoms in patients with COPD.
  
  
  CONCLUSIONS
  The severity of hyperinflation and dyspnea may be important associated risk factors for the incidence of GERD symptoms in patients with clinically stable COPD.
authors.affiliation: Department of Respiratory Medicine, West China Hospital of Sichuan University, Chengdu, 610041, Sichuan Province, China.
authors.forename: Bin-Miao
authors.initials: BM
authors.lastname: Liang
authors.forename: Yu-Lin
authors.initials: YL
authors.lastname: Feng
mesh_terms: D000368:Aged; D002637:Chest Pain / Q000150:complications; D016001:Confidence Intervals; D005260:Female; D005541:Forced Expiratory Volume; D005764:Gastroesophageal Reflux / Q000150:complications* / Q000503:physiopathology; D006356:Heartburn / Q000150:complications; D006801:Humans; D007320:Inspiratory Capacity; D057045:Laryngopharyngeal Reflux / Q000150:complications; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D029424:Pulmonary Disease, Chronic Obstructive / Q000150:complications* / Q000503:physiopathology; D012115:Residual Volume; D011795:Surveys and Questionnaires