title: Increasing body weight enhances prevalence and proximal extent of reflux in GERD patients 'on' and 'off' PPI therapy.
abstract: BACKGROUND
  Increased body weight is associated with higher intragastric pressure. Proximal extent of reflux is a determinant of symptoms in patients with gastro-esophageal reflux disease (GERD). We aimed to investigate the association between body mass index (BMI) and abdominal circumference on the incidence and proximal extent of reflux.
  
  
  METHODS
  A total of 95 patients [37 men, age 51(16-82) years] with typical and/or atypical GERD symptoms underwent 24 h impedance-pH monitoring. Forty-nine patients were studied 'off' and 46 'on' proton pump inhibitors (PPI) treatment. Reflux was classified as acid (pH < 4) or weakly acidic (pH 4-7). Proximal extent was defined as the number of reflux events reaching ≥15 cm above the lower esophageal sphincter. Body mass index and abdominal circumference (cm) were assessed.
  
  
  RESULTS
  In patients 'off' PPI, there was a correlation between BMI and esophageal acid exposure (ρ = 0.53, P < 0.001), volume exposure (ρ = 0.48, P < 0.001), total number of reflux events (ρ = 0.47, P < 0.001) and number of acid reflux events (ρ = 0.49, P < 0.001). In patients 'on' PPI there was a correlation between BMI and esophageal acid exposure (ρ = 0.32, P = 0.03), volume exposure (ρ = 0.46, P < 0.01) and total number of reflux events (ρ = 0.33, P = 0.03). Similar correlations were found between abdominal circumference and reflux. A correlation between BMI and proximal extent of reflux was present in patients 'off' PPI (ρ = 0.32, P = 0.03). In patients 'on' PPI, we found a correlation between abdominal circumference and proximal extent (ρ = 0.31, P = 0.03).
  
  
  CONCLUSIONS
  Body mass index and abdominal circumference may contribute to GER and its proximal extent, in patients 'on and 'off' PPI. Further studies investigating the role of weight reduction in the control of GERD symptoms are warranted.
authors.affiliation: Translational Research Center for Gastrointestinal Disorders, K.U. Leuven, 49 Herestraat, Leuven, Belgium. jan.tack@med.kuleuven.be
authors.forename: K
authors.initials: K
authors.lastname: Blondeau
authors.forename: V
authors.initials: V
authors.lastname: Boecxstaens
authors.forename: L
authors.initials: L
authors.lastname: Van Oudenhove
authors.forename: R
authors.initials: R
authors.lastname: Farré
authors.forename: G
authors.initials: G
authors.lastname: Boeckxstaens
authors.forename: J
authors.initials: J
authors.lastname: Tack
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D015992:Body Mass Index; D001835:Body Weight; D017097:Electric Impedance; D050782:Esophageal pH Monitoring; D005764:Gastroesophageal Reflux / Q000188:drug therapy* / Q000453:epidemiology / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D054328:Proton Pump Inhibitors / Q000627:therapeutic use*; D015430:Weight Gain; D055815:Young Adult
chemical_list: D054328:Proton Pump Inhibitors