title: White blood cell count and risk of gastric cancer incidence in a general Japanese population: the Hisayama study.
abstract: The authors examined the association between white blood cell (WBC) count and the development of gastric cancer in a 19-year follow-up study of 2,558 Japanese subjects aged ≥40 years (1988-2007). The subjects were stratified into 4 groups according to baseline WBC quartile (≤4.4, 4.5-5.2, 5.3-6.3, or ≥6.4 × 10(3) cells/μL). During follow-up, 128 subjects developed gastric cancer. The age- and sex-adjusted incidence of gastric cancer increased linearly with higher WBC level: 1.7, 2.6, 3.9, and 5.4 per 1,000 person-years, respectively, for the 4 quartile groups (P for trend < 0.01). The risk of gastric cancer was 2.22-fold (95% confidence interval: 1.19, 4.14) higher in the highest WBC quartile group than in the lowest group after adjustment for confounding factors. With respect to Helicobacter pylori infection status, H. pylori-seropositive subjects in the highest WBC quartile group showed a significantly greater risk of gastric cancer than those in the lower 3 quartile groups, whereas such an association was not observed in H. pylori-seronegative subjects. There was no evidence of heterogeneity in the association (P for heterogeneity = 0.65). The study findings suggest that higher WBC levels are a risk factor for gastric cancer, especially in subjects with H. pylori infection.
authors.affiliation: Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Fukuoka City, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Iida
authors.forename: Fumie
authors.initials: F
authors.lastname: Ikeda
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Ninomiya
authors.forename: Koji
authors.initials: K
authors.lastname: Yonemoto
authors.forename: Yasufumi
authors.initials: Y
authors.lastname: Doi
authors.forename: Jun
authors.initials: J
authors.lastname: Hata
authors.forename: Takayuki
authors.initials: T
authors.lastname: Matsumoto
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Iida
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Kiyohara
mesh_terms: D000328:Adult; D000368:Aged; D004032:Diet; D005260:Female; D005500:Follow-Up Studies; D006306:Health Surveys; D016481:Helicobacter Infections / Q000150:complications*; D016480:Helicobacter pylori / Q000302:isolation & purification*; D006801:Humans; D015994:Incidence; D007564:Japan / Q000453:epidemiology; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D013274:Stomach Neoplasms / Q000453:epidemiology / Q000209:etiology* / Q000276:immunology