title: Impact of pre-diagnosis behavior on risk of death from esophageal cancer: a systematic review and meta-analysis.
abstract: OBJECTIVE
  Most people diagnosed with esophageal cancer will die from their disease, but it is not known whether survival is influenced by pre-morbid behavior. We undertook a systematic review and meta-analysis to investigate the impact of pre-diagnosis behavior on risk of death for esophageal cancer.
  
  
  METHODS
  We performed a systematic review of studies reporting on the relationship between pre-diagnosis smoking, alcohol consumption, overweight and obesity, physical activity and regular consumption of nonsteroidal anti-inflammatory drugs, and risk of death from esophageal squamous cell carcinoma (ESCC) and adenocarcinomas (EACs). Study characteristics are presented and aggregate results are compiled using meta-analysis.
  
  
  RESULTS
  From an initial pool of 644 non-duplicate records, 13 articles arising from 12 studies met the inclusion criteria. Considerable variation was observed between studies in location, measurement categories, adjustment for other risks, and results. Pooled estimates suggested that for ESCC pre-diagnosis smoking was associated with a 1.19 times [95 % confidence interval (CI) 1.04-1.36] increased risk of death and pre-diagnosis alcohol consumption with a 1.36 times increased risk of death (95 % CI 1.15-1.61). No significant effects were observed for EAC. We observed a lower risk of death for both ESCC and EAC associated with high pre-diagnosis body mass index (BMI) ≥25 kg/m(2) (ESCC hazard ratio 0.80, 95 % CI 0.67-0.95; EAC 0.80, 95 % CI 0.68-0.95), although there was significant heterogeneity across studies.
  
  
  CONCLUSIONS
  Our findings suggest that a number of modifiable pre-diagnosis risk factors have a carryover effect on the risk of death from esophageal cancer. These include smoking, drinking alcohol, and BMI.
authors.affiliation: Centre for Research in Mathematics, University of Western Sydney, Sydney, NSW, Australia. p.fahey@uws.edu.au.|School of Science and Health, University of Western Sydney, Sydney, NSW, Australia. p.fahey@uws.edu.au.
authors.forename: Paul P
authors.identifier: http://orcid.org/0000-0002-6351-9876
authors.initials: PP
authors.lastname: Fahey
authors.affiliation: Faculty of Medicine, University of New South Wales, Sydney, NSW, Australia.
authors.forename: Kylie-Ann
authors.initials: KA
authors.lastname: Mallitt
authors.affiliation: School of Science and Health, University of Western Sydney, Sydney, NSW, Australia.
authors.forename: Thomas
authors.initials: T
authors.lastname: Astell-Burt
authors.affiliation: Centre for Research in Mathematics, University of Western Sydney, Sydney, NSW, Australia.|School of Computing, Engineering and Mathematics, University of Western Sydney, Sydney, NSW, Australia.
authors.forename: Glenn
authors.initials: G
authors.lastname: Stone
authors.affiliation: QIMR Berghofer Medical Research Institute, Brisbane, QLD, Australia.
authors.forename: David C
authors.initials: DC
authors.lastname: Whiteman
mesh_terms: D000230:Adenocarcinoma / Q000401:mortality*; D000428:Alcohol Drinking / Q000009:adverse effects*; D015992:Body Mass Index; D002294:Carcinoma, Squamous Cell / Q000401:mortality*; D004938:Esophageal Neoplasms / Q000401:mortality*; D000077277:Esophageal Squamous Cell Carcinoma; D015438:Health Behavior; D006801:Humans; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*
keywords: Esophageal adenocarcinoma; Esophageal squamous cell carcinoma; Health behavior; Risk of death