Abstract 2174: Association of diabetes and obesity with risk of esophageal and gastric adenocarcinoma in the Iowa Women's Health Study (IWHS)

Abstract

Incidence rates of esophageal and gastric cancers have increased rapidly in developing countries during the past four decades. The rate of esophageal adenocarcinomas has approximately tripled among US whites and now exceeds that of esophageal squamous cell carcinomas. Incidence of gastric cardia adenocarcinomas has also risen significantly during this period, though to a lesser extent. These cancers often respond poorly to treatment, highlighting the importance of identifying modifiable risk factors with a view to prevention. The association between diabetes and gastroesophageal adenocarcinoma has been examined in only a few studies and findings are inconsistent. While obesity is a significant risk factor for esophageal and gastric adenocarcinomas, few analyses have been conducted in prospective cohorts. We examined the association between diabetes, BMI, and waist circumference and incidence of esophageal, non-cardia gastric and gastric cardia adenocarcinomas in a large prospective cohort of postmenopausal women. A mailed survey at baseline (1986) collected information on self-reported diabetes and anthropometric measures and included a detailed food-frequency questionnaire. The 34,466 initially cancer free women were followed for 24 years with annual cancer incidence obtained through the State Health Registry of Iowa, part of the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) Program; 83 women developed gastroesophageal adenocarcinoma. Associations were examined using proportional hazards regression models: hazard ratios (HR) and 95% confidence intervals (CI) were calculated. Significant associations were observed in age-adjusted models for diabetes (yes/no) [HR: 2.09, 95% CI: 1.01-4.34], body mass index (kg per meters squared) [HR: 1.09, 95% CI: 1.03-1.15], and waist circumference (cm) [HR: 1.24, 95% CI: 1.01-1.53]. Additionally, a positive association between diabetes and adenocarcinoma of the gastroesophageal junction was found in both age-adjusted [HR: 3.43, 95% CI: 1.32-8.90] and multivariate-adjusted models [HR: 3.00, 95% CI: 1.13-7.99]. An inverse association was found with increasing daily fiber intake (g/day) and all gastroesophageal adenocarcinomas [HR: 0.84, 95% CI: 0.73-0.96]. These findings support the view that diabetes, body mass index and waist circumference increase risk of gastroesophageal adenocarcinoma while increased fiber intake may decrease risk. Citation Format: Bryan P. LaBore, Anna E. Prizment, Frank G. Ondrey, Kristin E. Anderson. Association of diabetes and obesity with risk of esophageal and gastric adenocarcinoma in the Iowa Women's Health Study (IWHS). [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2174. doi:10.1158/1538-7445.AM2014-2174