title: The feasibility of an exercise intervention in males at risk of oesophageal adenocarcinoma: a randomized controlled trial.
abstract: OBJECTIVE
  To investigate the feasibility and safety of a 24-week exercise intervention, compared to control, in males with Barrett's oesophagus, and to estimate the effect of the intervention, compared to control, on risk factors associated with oesophageal adenocarcinoma development.
  
  
  METHODS
  A randomized controlled trial of an exercise intervention (60 minutes moderate-intensity aerobic and resistance exercise five days/week over 24 weeks; one supervised and four unsupervised sessions) versus attention control (45 minutes stretching five days/week over 24 weeks; one supervised and four unsupervised sessions) in inactive, overweight/obese (25.0-34.9 kg/m2) males with Barrett's oesophagus, aged 18-70 years. Primary outcomes were obesity-associated hormones relevant to oesophageal adenocarcinoma risk (circulating concentrations of leptin, adiponectin, interleukin-6, tumour necrosis factor-alpha, C-reactive protein, and insulin resistance [HOMA]). Secondary outcomes included waist circumference, body composition, fitness, strength and gastro-oesophageal reflux symptoms. Outcomes were measured at baseline and 24-weeks. Intervention effects were analysed using generalised linear models, adjusting for baseline value.
  
  
  RESULTS
  Recruitment was difficult in this population with a total of 33 participants recruited (target sample size: n = 80); 97% retention at 24-weeks. Adherence to the exercise protocol was moderate. No serious adverse events were reported. A statistically significant intervention effect (exercise minus control) was observed for waist circumference (-4.5 [95% CI -7.5, -1.4] cm; p < 0.01). Effects on primary outcomes were not statistically significant.
  
  
  CONCLUSIONS
  This small, exploratory trial provides important information to inform future trial development including recruitment rates and estimates of effect sizes on outcomes related to oesophageal adenocarcinoma risk. Future trials should investigate a combined dietary and exercise intervention to achieve greater weight loss in this population and relax inclusion criteria to maximize recruitment.
  
  
  BACKGROUND
  Australian New Zealand Clinical Trials Registry (ANZCTR) ACTRN12609000401257.
authors.affiliation: Burns, Trauma and Critical Care Research Centre, School of Medicine, The University of Queensland, Brisbane, Australia.
authors.forename: Brooke M
authors.initials: BM
authors.lastname: Winzer
authors.affiliation: Burns, Trauma and Critical Care Research Centre, School of Medicine, The University of Queensland, Brisbane, Australia.
authors.forename: Jennifer D
authors.initials: JD
authors.lastname: Paratz
authors.affiliation: Metabolic Medicine Group, Mater Research Institute University of Queensland, Brisbane, Australia.
authors.forename: Jonathan P
authors.initials: JP
authors.lastname: Whitehead
authors.affiliation: Cancer Control Group, QIMR Berghofer Medical Research Institute, Brisbane, Australia.
authors.forename: David C
authors.initials: DC
authors.lastname: Whiteman
authors.affiliation: Cancer Prevention Research Centre, School of Public Health, The University of Queensland, Brisbane, Australia.
authors.forename: Marina M
authors.initials: MM
authors.lastname: Reeves
mesh_terms: D000230:Adenocarcinoma / Q000097:blood / Q000378:metabolism / Q000503:physiopathology*; D052242:Adiponectin / Q000097:blood; D001471:Barrett Esophagus / Q000097:blood / Q000378:metabolism / Q000503:physiopathology; D002097:C-Reactive Protein / Q000378:metabolism; D016022:Case-Control Studies; D004938:Esophageal Neoplasms / Q000097:blood / Q000378:metabolism / Q000503:physiopathology*; D015444:Exercise / Q000502:physiology*; D006801:Humans; D007333:Insulin Resistance / Q000502:physiology; D015850:Interleukin-6 / Q000097:blood; D020738:Leptin / Q000097:blood; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000378:metabolism / Q000503:physiopathology; D050177:Overweight / Q000097:blood / Q000378:metabolism / Q000503:physiopathology; D012307:Risk Factors; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
chemical_list: D052242:Adiponectin; C508600:IL6 protein, human; D015850:Interleukin-6; D020738:Leptin; C439524:TNF protein, human; D014409:Tumor Necrosis Factor-alpha; D002097:C-Reactive Protein