title: Analysis of demographic characteristics in 3242 young age gastric cancer patients in Korea.
abstract: OBJECTIVE
  To evaluate the epidemiologic features of young age gastric cancer (GC).
  
  
  METHODS
  Retrospectively, a total of 3242 patients with GC between 18 and 45 years of age and 3000 sex- and age-matched controls were reviewed. All subjects were stratified into 3 groups based on age (A, 18-30 years; B, 31-40 years; C, 41-45 years). Epidemiologic characteristics and risk factors were investigated with reference to their age and gender.
  
  
  RESULTS
  Compared to controls, more frequent intake of high risk diet (P = 0.00075), history of heavy smoking (P = 0.00087), intake of heavy alcohol (P = 0.00091), lower social economic status (P = 0.00083), body mass index > 30 (P = 0.00097), urban residence (P = 0.00065), and more frequent exposure to harmful occupational environments (P = 0.00072) were observed in all age groups and both genders in young age GC. These relationships were weaker in females compared to males of the same age, and were stronger as the age of patients increased. However, in group C of young age GC patients, environmental factors played important roles in females and males with a similar body weight. In females, older age at first delivery (> 35 years), lack of lactation history, nulliparity, and poor nutritional status during pregnancy were significantly associated with an increased risk of GC (P = 0.00034). In this study, 252 patients (7.8%) had a family history of GC with high odds ratio (OR) (3.22-4.21). In particular, family history was more closely associated with GC in males (OR, 4.21 in male vs 3.46 in female) and more advanced cases (P = 0.00051).
  
  
  CONCLUSIONS
  Hormonal associated factors were more commonly associated with females whereas environmental factors were more commonly associated with males in young age GC patients.
authors.affiliation: Department of Gastroenterology, Yonsei University College of Medicine, 134 Shinchon-dong, Seodaemun-gu, 120-752 Seoul, South Korea.
authors.forename: Hye Won
authors.initials: HW
authors.lastname: Chung
authors.forename: Sung Hoon
authors.initials: SH
authors.lastname: Noh
authors.forename: Jong-Baeck
authors.initials: JB
authors.lastname: Lim
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D015992:Body Mass Index; D016022:Case-Control Studies; D003710:Demography; D004032:Diet / Q000009:adverse effects; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D012307:Risk Factors; D012727:Sex Characteristics; D012907:Smoking / Q000009:adverse effects; D012923:Social Class; D013274:Stomach Neoplasms / Q000453:epidemiology* / Q000208:ethnology*; D055815:Young Adult