No abstract

BACKGROUND & AIMS Individuals with Barrett’s esophagus (BE) have an increased risk of developing esophageal adenocarcinoma (EA). Obesity contributes to development of BE and its progression to cancer. We investigated the roles of obesity-induced hyperinsulinemia and dysregulation of adipokines in these processes. METHODS We measured fasting levels of glucose, insulin, leptin, and adiponectin in 392 patients enrolled in the Seattle BE Study. We calculated homeostatic model assessment (HOMA) scores (a measure of insulin sensitivity) and identified subjects with metabolic syndrome. We evaluated the association between these measures and risk of EA using Cox regression models adjusted for known risk factors. RESULTS Increasing HOMA scores were associated with increasing risk for EA; the strongest association was observed within the first 3 years after participants entered the study (hazard ratio (HR)=2.45; 95% confidence interval [CI], 1.43–4.1; Ptrend=.001). Leptin level was also significantly associated with increased risk of EA within 3 y (HR=2.51; 95% CI 1.09–5.81; Ptrend =0.03) and 6 y (HR=2.07; 95% CI 1.01–4.26; Ptrend=0.048) of baseline. The level of high molecular weight adiponectin had a non-linear inverse association with risk of EA; the strongest associations were observed in the second tertile (HR=0.34; 95% CI, 0.14–0.82). Metabolic syndrome was not associated with risk of EA. CONCLUSIONS Among patients with BE, increased levels of leptin and insulin resistance are associated with increased risk for EA, whereas increased level of high molecular weight adiponectin is inversely associated with EA. These biomarkers might be used to determine cancer risk among patients with BE.

People with a high genetic propensity to obesity have higher risks of esophageal metaplasia and neoplasia than people with low genetic propensity. These analyses provide the strongest evidence to date that obesity is independently associated with BE and EAC, and is not due to confounding or bias inherent in conventional epidemiologic analyses.