title: Effect of body mass index on adenocarcinoma of gastric cardia.
abstract: OBJECTIVE
  Obesity has been proved as one of the main risk factors for gastric cardia adenocarcinoma (GCA) in the West. The objective of our research was to evaluate the relationship between obesity and the risk of GCA in people from North China.
  
  
  METHODS
  A total of 300 patients who had been diagnosed as GCA and had accepted surgical operation at Beijing Cancer Hospital from 1995 to 2002 were enrolled. Data were collected from pathology materials and hospital records. Two hundred and fifty-eight healthy people who had accepted health examination at the same hospital during the same period were enrolled as controls. Height, weight and gender of them at the time of examination were also collected. Obesity was estimated by body mass index (BMI), computed as weight in kilograms per square surface area (Kg/m2). The degree of obesity was determined by using BMI< or =18.5, 24-27.9 and > or =28 (Kg/m2) as the cut-off points for underweight/normal, overweight and obesity, respectively. Associations with obesity were estimated by odds ratios (ORs) and 95 % confidence intervals (CIs). All ORs were adjusted for age and sex.
  
  
  RESULTS
  The mean level of BMI was significantly lower in the patient group than that in the control group. The ORs for obesity in age groups 30-59 and 60-79 were 1.15 (95% CI=0.37-3.65) and 0.16 (95% CI=0.05-0.44) for males and 0.78 (95% CI=0.26-2.36) and 0.28 (95% CI=0.04-2.05) for females, respectively. The ORs for underweight were 2.42 (95% CI=0.56-10.53) and 4.68 (95% CI=1.13-19.40) for males in age subgroups 30-59 and 60-79 and 40.7 (95% CI=9.32-177.92) for females older than 60 yrs. BMI was significantly associated with GCA (P<0.01). Underweight people were at high risk for GCA.
  
  
  CONCLUSIONS
  BMI is an independent risk factor for GCA. Underweight is positively associated with GCA.
authors.affiliation: Department of Surgery, Beijing Cancer Hospital, Beijing Institute of Cancer Research, School of Oncology, Peking University, Beijing 100036, China.
authors.forename: Ji
authors.initials: J
authors.lastname: Zhang
authors.forename: Xiang-Qian
authors.initials: XQ
authors.lastname: Su
authors.forename: Xiao-Jiang
authors.initials: XJ
authors.lastname: Wu
authors.forename: Ya-Hang
authors.initials: YH
authors.lastname: Liu
authors.forename: Hua
authors.initials: H
authors.lastname: Wang
authors.forename: Xiang-Nong
authors.initials: XN
authors.lastname: Zong
authors.forename: Yi
authors.initials: Y
authors.lastname: Wang
authors.forename: Jia-Fu
authors.initials: JF
authors.lastname: Ji
mesh_terms: D000230:Adenocarcinoma / Q000453:epidemiology* / Q000601:surgery; D000328:Adult; D000368:Aged; D015992:Body Mass Index; D002681:China / Q000453:epidemiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000453:epidemiology*; D012016:Reference Values; D012044:Regression Analysis; D012189:Retrospective Studies; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000453:epidemiology* / Q000601:surgery