Racial and Ethnic Minorities at Increased Risk for Gastric Cancer in a Regional US Population Study
AbstractBACKGROUND AND AIMS
Limited data are available on risk factors for gastric cancer in the United States. We aimed to characterize risk for gastric cancer based on race/ethnicity and additional established risk factors.METHODS
We conducted a retrospective cohort study from 2008 to 2014 from an integrated health care system in Southern California to assess incidence of gastric cancer by race/ethnicity. We then conducted an age- and sex-matched case-cohort study to evaluate additional risk factors:Helicobacter pyloriinfection, tobacco use, family history, obesity, language, and socioeconomic status. Subgroup analysis was performed for language and socioeconomic status by race/ethnicity.RESULTS
The incidence of gastric cancer in the reference (non-Hispanic white) population was 8.2 (95% confidence interval [CI], 7.7–8.7) cases per 100,000 person-years. Incidence values for Asians, Hispanics, and non-Hispanic black persons were higher: 12.7 (95% CI, 11.1–14.3), 12.7 (95% CI, 11.7–13.7), and 11.8 (95% CI, 10.3–13.2) cases per 100,000 person-years, respectively (allP< .0001). In logistic regression analysis, we found race/ethnicity to be an independent risk factor for gastric cancer; the odds ratio (OR) for non-Hispanic black persons was 1.5 (95% CI, 1.22–1.72;P< .0001), the OR for Hispanics was 1.4 (95% CI, 1.22–1.57;P< .0001), and the OR for Asians was 1.5 (95% CI, 1.28–1.81;P< .0001), compared with the non-Hispanic white population. Other independent risk factors included infection withH pylori(OR, 4.6; 95% CI, 3.8–5.7), smoking history (OR, 1.4; 95% CI, 1.3–1.6), and family history of gastric cancer (OR, 3.4; 95% CI, 2.6–4.4) (allP< .0001). Non-English language was a significant risk factor for gastric cancer in Asians (P= .05). Higher annual median income was associated with reduced risk (OR, 0.84; 95% CI, 0.75–0.95;P= .0004).CONCLUSIONS
In a population study in Southern California, we found racial/ethnic minorities to have a 40%–50% increase in risk of gastric cancer compared with the non-Hispanic white population. In addition toH pyloriinfection, smoking, family history, and low socioeconomic status were also associated with increased risk. Further characterization of high-risk groups may identify populations appropriate for targeted screening.