title: Increasing insulin resistance is associated with increased severity and prevalence of gastro-oesophageal reflux disease.
abstract: BACKGROUND
  The diagnosis of gastro-oesophageal reflux disease (GERD) is based on reflux symptoms. Although metabolic syndrome has been linked to erosive oesophagitis (EO), the impact of insulin resistance, the core of the metabolic syndrome, on reflux symptoms remains to be elucidated.
  
  
  OBJECTIVE
  To assess the effects of insulin resistance on GERD, including both endoscopic findings and symptoms.
  
  
  METHODS
  A total of 743 sonographic noncirrhotic adult subjects, who underwent an upper gastrointestinal endoscopic examination, completed a gastro-oesophageal reflux questionnaire and had available fasting insulin data were included. Endoscopic findings were classified according to the Los Angeles classification. Homeostatic model assessment-insulin resistance (HOMA-IR) index was used to evaluate the status of insulin resistance. Univariate and multivariate approaches were used to evaluate the associations between insulin resistance and GERD.
  
  
  RESULTS
  Older age, male gender, smoking and alcohol consumption increased the prevalence of EO, but not GERD symptoms. A large waist circumference, high fasting blood glucose levels and high number of metabolic syndrome components were associated with increased prevalence of both EO and GERD symptoms, while high blood pressure was associated with increased prevalence of EO only. Moreover, higher scores in the gastro-oesophageal reflux questionnaire were associated with higher HOMA-IR index, and higher HOMA-IR index was associated with increased prevalence of EO (adjusted odds ratio 1.14, 95% CI 1.03-1.26, P = 0.012).
  
  
  CONCLUSIONS
  Our findings demonstrate clear associations between insulin resistance, metabolic syndrome and GERD. Whether reducing insulin resistance may improve GERD symptoms or EO deserves prospective study.
authors.affiliation: Division of Gastroenterology, Department of Internal Medicine, Buddhist Tzu Chi General Hospital, Taipei Branch, Taiwan.
authors.forename: C-S
authors.initials: CS
authors.lastname: Hsu
authors.forename: P-C
authors.initials: PC
authors.lastname: Wang
authors.forename: J-H
authors.initials: JH
authors.lastname: Chen
authors.forename: W-C
authors.initials: WC
authors.lastname: Su
authors.forename: T-C
authors.initials: TC
authors.lastname: Tseng
authors.forename: H-D
authors.initials: HD
authors.lastname: Chen
authors.forename: T-H
authors.initials: TH
authors.lastname: Hsiao
authors.forename: C-C
authors.initials: CC
authors.lastname: Wang
authors.forename: H H
authors.initials: HH
authors.lastname: Lin
authors.forename: R-Y
authors.initials: RY
authors.lastname: Shyu
authors.forename: Y-C
authors.initials: YC
authors.lastname: Chao
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D004724:Endoscopy; D005260:Female; D005764:Gastroesophageal Reflux / Q000503:physiopathology*; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D015995:Prevalence; D012307:Risk Factors; D012720:Severity of Illness Index; D012737:Sex Factors; D011795:Surveys and Questionnaires; D013624:Taiwan / Q000453:epidemiology; D014463:Ultrasonography