title: Relationship between body mass index and the risk of early gastric cancer and dysplasia regardless of Helicobacter pylori infection.
abstract: Obesity is known to be associated with an increased risk of gastric cardia cancer but not with noncardia cancer. In terms of gastric dysplasia, few studies have evaluated its relationship with obesity. In addition, no study on the relationship between obesity and the risk of gastric cancer has analyzed the status of Helicobacter pylori infection.
  
  
  
  A case-control study was designed to investigate the relationship between obesity and the risk of gastric cancer and dysplasia adjusted for the status of H. pylori infection in Koreans. Nine hundred ninety-eight gastric cancer patients, 313 gastric dysplasia patients, and 1,288 subjects with normal endoscopic findings were included.
  
  
  
  As gender differences could be the largest confounding factor, the risk of gastric cancer and dysplasia with an increasing body mass index (BMI) was analyzed in men and women, separately, and was adjusted for age, smoking, drinking, family history of gastric cancer, H. pylori infection, atrophic gastritis, intestinal metaplasia, and serum pepsinogen I/pepsinogen II ratio. Obesity (BMI 25 kg/m(2) or greater but less than 30 kg/m(2)) was associated with increased risk of early gastric cancer [adjusted odds ratio (aOR) 1.657; 95 % confidence interval (CI) 1.086-2.528; P = 0.019] and well or moderately differentiated adenocarcinoma (aOR 1.566; 95 % CI 1.011-2.424; P = 0.044) compared with normal BMI status (BMI < 23 kg/m(2)) in men. Obesity was related to gastric dysplasia (aOR 2.086; 95 % CI 1.011-4.302; P = 0.047) in women.
  
  
  
  The effect of obesity on gastric cancer showed a gender difference. That is, in men it was related to increased risk of early gastric cancer and well or moderately differentiated adenocarcinoma, but it was associated with gastric dysplasia in women regardless of H. pylori infection in Korea. Further research into this difference is necessary.
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, 173-82 Gumi-ro, Bundang-gu, Seongnam, Gyeonggi-do, 463-707, South Korea.
authors.forename: Hee Jin
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, 173-82 Gumi-ro, Bundang-gu, Seongnam, Gyeonggi-do, 463-707, South Korea. nayoungkim49@empal.com.|Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, South Korea. nayoungkim49@empal.com.
authors.forename: Nayoung
authors.initials: N
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, 173-82 Gumi-ro, Bundang-gu, Seongnam, Gyeonggi-do, 463-707, South Korea.
authors.forename: Hyun Young
authors.initials: HY
authors.lastname: Kim
authors.affiliation: Department of Pathology, Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, South Korea.
authors.forename: Hye Seung
authors.initials: HS
authors.lastname: Lee
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, 173-82 Gumi-ro, Bundang-gu, Seongnam, Gyeonggi-do, 463-707, South Korea.
authors.forename: Hyuk
authors.initials: H
authors.lastname: Yoon
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, 173-82 Gumi-ro, Bundang-gu, Seongnam, Gyeonggi-do, 463-707, South Korea.
authors.forename: Cheol Min
authors.initials: CM
authors.lastname: Shin
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, 173-82 Gumi-ro, Bundang-gu, Seongnam, Gyeonggi-do, 463-707, South Korea.
authors.forename: Young Soo
authors.initials: YS
authors.lastname: Park
authors.affiliation: Department of Surgery, Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, South Korea.
authors.forename: Do Joong
authors.initials: DJ
authors.lastname: Park
authors.affiliation: Department of Surgery, Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, South Korea.
authors.forename: Hyung Ho
authors.initials: HH
authors.lastname: Kim
authors.affiliation: Department of Radiology, Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, South Korea.
authors.forename: Kyoung-Ho
authors.initials: KH
authors.lastname: Lee
authors.affiliation: Department of Radiology, Seoul National University Bundang Hospital, Seongnam, Gyeonggi-do, South Korea.
authors.forename: Young-Hoon
authors.initials: YH
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Yonsei University Wonju College of Medicine, Wonju, South Korea.
authors.forename: Hee Man
authors.initials: HM
authors.lastname: Kim
authors.affiliation: Department of Internal Medicine, Seoul National University Bundang Hospital, 173-82 Gumi-ro, Bundang-gu, Seongnam, Gyeonggi-do, 463-707, South Korea.|Department of Internal Medicine and Liver Research Institute, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Dong Ho
authors.initials: DH
authors.lastname: Lee
mesh_terms: D000230:Adenocarcinoma / Q000453:epidemiology*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015992:Body Mass Index; D016022:Case-Control Studies; D005260:Female; D016481:Helicobacter Infections / Q000150:complications / Q000453:epidemiology; D016480:Helicobacter pylori; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000150:complications*; D011230:Precancerous Conditions / Q000453:epidemiology*; D056910:Republic of Korea; D012307:Risk Factors; D012737:Sex Factors; D013274:Stomach Neoplasms / Q000453:epidemiology*
keywords: Body mass index; Gastric cancer; Gastric dysplasia; Helicobacter pylori