title: Gastroesophageal and laryngopharyngeal reflux detected by 24-hour combined impedance and pH monitoring in healthy Chinese volunteers.
abstract: OBJECTIVE
  To define the normative data of gastroesophageal reflux (GER) and laryngopharyngeal reflux (LPR) in healthy Chinese volunteers.
  
  
  METHODS
  Healthy volunteers without gastrointestinal and throat disease and symptoms were enrolled and underwent 24-hour impedance-pH monitoring.
  
  
  RESULTS
  A total of 37 healthy volunteers completed all the tests (female 54.1%; age 38.0±15.2 years). Of 1862 GER, 49.6% were mixed, 40.9% were liquid and 9.5% were gas. More than half (54.9%) were acid. The median and 95th percentile numbers of GER were 52 and 71, respectively. The number of LPR was eight, of which two were mixed and the others were liquid. Only one episode of reflux was classified as acid LPR. The median and 95th percentile numbers of LPR were 0 and 2, respectively. More liquid reflux were associated with LPR (P=0.02). Age had no influence on GER and LPR reflux profiles.
  
  
  CONCLUSIONS
  Few LPR occurred in healthy Chinese volunteers and they were rarely acid when they reached the larynx. LPR was mostly associated with liquid reflux.
authors: Departments of Gastroenterology Otorhinolaryngology, the First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong Province, China.
authors: An Jiang
authors: AJ
authors: Wang
authors: Mao Jin
authors: MJ
authors: Liang
authors: Ai Yun
authors: AY
authors: Jiang
authors: Jin Kun
authors: JK
authors: Lin
authors: Ying Lian
authors: YL
authors: Xiao
authors: Sui
authors: S
authors: Peng
authors: Jie
authors: J
authors: Chen
authors: Wei Ping
authors: WP
authors: Wen
authors: Min Hu
authors: MH
authors: Chen