During the past 40 years, esophageal/gastric cardia adenocarcinoma (EA/GCA) incidence increased in Westernized countries, but survival remained low. A parallel increase in sugar intake, which may facilitate carcinogenesis by promoting hyperglycaemia, led us to examine sugar/carbohydrate intake in association with EA/GCA incidence and survival.Methods:
We pooled 500 EA cases, 529 GCA cases and 2027 controls from two US population-based case-control studies with cases followed for vital status. Dietary intake, assessed by study-specific food frequency questionnaires, was harmonized and pooled to estimate 12 measures of sugar/carbohydrate intake. Multivariable-adjusted odds ratios (ORs) and hazard ratios [95% confidence intervals (CIs)] were calculated using multinomial logistic regression and Cox proportional hazards regression, respectively.Results:
EA incidence was increased by 51-58% in association with sucrose (ORQ5vs.Q1 = 1.51, 95% CI = 1.01-2.27), sweetened desserts/beverages (ORQ5vs.Q1 = 1.55, 95% CI = 1.06-2.27) and the dietary glycaemic index (ORQ5vs.Q1 = 1.58, 95% CI = 1.13-2.21). Body mass index (BMI) and gastro-esophageal reflux disease (GERD) modified these associations (Pmultiplicative-interaction ≤ 0.05). For associations with sucrose and sweetened desserts/beverages, respectively, the OR was elevated for BMI < 25 (ORQ4-5vs.Q1-3 = 1.79, 95% CI = 1.26-2.56 and ORQ4-5vs.Q1-3 = 1.45, 95% CI = 1.03-2.06), but not BMI ≥ 25 (ORQ4-5vs.Q1-3 = 1.05, 95% CI = 0.76-1.44 and ORQ4-5vs.Q1-3 = 0.85, 95% CI = 0.62-1.16). The EA-glycaemic index association was elevated for BMI ≥ 25 (ORQ4-5vs.Q1-3 = 1.38, 95% CI = 1.03-1.85), but not BMI < 25 (ORQ4-5vs.Q1-3 = 0.88, 95% CI = 0.62-1.24). The sucrose-EA association OR for GERD < weekly was 1.58 (95% CI = 1.16-2.14), but for GERD ≥ weekly was 1.01 (95% CI = 0.70-1.47). Sugar/carbohydrate measures were not associated with GCA incidence or EA/GCA survival.Conclusions:
If confirmed, limiting intake of sucrose (e.g. table sugar), sweetened desserts/beverages, and foods that contribute to a high glycaemic index, may be plausible EA risk reduction strategies.