Published online Jul 7, 2015. doi: 10.3748/wjg.v21.i25.7805
Peer-review started: December 21, 2014
First decision: January 13, 2015
Revised: March 13, 2015
Accepted: April 3, 2015
Article in press: April 3, 2015
Published online: July 7, 2015
AIM: To investigate whether regional geography influences ethnic and gender trends for the development of gastric cancer (GC).
METHODS: This retrospective analysis of the INVISION patient database at Louisiana State University Health Sciences Center-Shreveport (LSUHSC-S), a southern United States regional hospital, was performed from 2005-2011. Using the international statistical classification of diseases 9 (ICD-9), inpatient, day surgery outpatient, and emergency outpatient diagnosis codes entered into medical records were used to identify GC patients. For each study year, the patients were evaluated for age, ethnicity, and gender, and each patient was counted only once throughout the study. Subsequent patient encounters were counted as visits and separated by inpatient and clinic visits. Complex or severe disease may require more frequent and intensive clinical management; therefore, we evaluated annual clinic visits as “surrogate markers” of disease severity. Finally, we studied the primary diagnosis for Helicobacter pylori (H. pylori) infection (ICD-9 code 41.86) as an additional factor that might increase the risk of GC.
RESULTS: A total of 285 patients were diagnosed with GC at LSUHSC-S between 2005 and 2011. African Americans (181 patients, 89 males and 92 females, 63.5% of total patients) had significantly higher frequencies of GC diagnosis compared with non-Hispanic whites (104 patients, 54 males and 50 females, 36.5% of total patients), at a ratio of 1.74 (P = 0.002). Within each ethnic group, men and women were diagnosed at approximately equal annual rates. Our findings differed significantly from United States national trends, which found that African American females and white females had lower risks for GC than their corresponding male counterparts. The United States national trend between 2005 and 2011 showed that African Americans males had a higher incidence of GC, with an annual mean (per 100000) of 16.31 ± 0.76 compared with white males (9 ± 0.1, P < 0.001), African American females (8.7 ± 0.34, P < 0.001) and white females (4.05 ± 0.07, P < 0.001). Among the GC patients, the number of clinic visits was highest among African American males (195.1 ± 28.1), who had significantly more clinic visits than African Americans females (123 ± 13.02, P < 0.05), white males (41.57 ± 4.74, P < 0.001) and white females (35 ± 8.9, P < 0.001). Similar trends were found for inpatient visits, with an annual mean of 11.43 ± 1.5 for African American males, followed by African American females (7.29 ± 1.36), white males (2.57 ± 0.69) and white females (1.57 ± 0.612). African American males had significantly more inpatient visits than white males (P < 0.001), and African American females had more inpatient visits than white females (P < 0.01). African American patients showed the highest frequency of H. pylori positive status, with approximately 72% vs 28% for the white patients.
CONCLUSION: Increase in GC diagnoses among women at LSUHSC-S is significantly higher than United States national averages, suggesting local geographic and socioeconomic influences may alter GC disease course.
Core tip: Gastric cancer (GC) remains a leading cause of morbidity and mortality. Nationally, AAs reportedly develop GC at twice the rate of Caucasians. Male gender is a significant risk factor for GC development in the United States with a nearly 2:1 male to female dominance. However, at Louisiana State University Health Sciences Center-Shreveport, the annual rates of GC diagnosis among women in either ethnic grouping were statistically indistinguishable from that of their male counterparts. This result indicates that regional geography and socioeconomic factors may contribute to the ethnicity and gender differences observed in patients with GC. Therefore, additional GC surveillance for women, particularly African American females, may improve patient outcomes.