Dietary patterns and risk of urinary tract tumors: a multilevel analysis of individuals in rural and urban contexts.

INTRODUCTION
Bladder cancer is the fourth most frequently diagnosed malignancy in males in Cordoba, Argentina. The evidence regarding an association between urinary tract tumors and dietary factors still remains controversial. Argentina has particular dietary habits, which have already been associated with cancer occurrence.

PURPOSES
(a) To estimate the association of typical dietary patterns in Argentina on the occurrence of urinary tract tumors and (b) to assess the urban-rural context of residence and cancer occurrence dependency.

METHODS
A case-control study of urinary tract tumors (n = 123, 41/82 cases/controls) was performed in Cordoba Province (Argentina), 2006-2011. A two-level logistic regression model was fitted, taking into account rural-urban residence. An exhaustive probabilistic sensitivity analysis (bias analysis) was performed.

RESULTS
Southern Cone pattern, characterized by red meat, starchy vegetables and wine consumptions (OR 1.75 high versus low level of adherence to the pattern), and a medium adherence to a high-sugar drinks pattern, with high loadings for soft drinks (OR 2.55), were associated with increasing risk of urinary tract tumors. High adherence to the latter pattern was inversely associated (OR 0.72). The occurrence of urinary tract tumors was also linked to place of residence (urban-rural), explaining more than 20 % of outcome variability and improving the above risk estimations.

CONCLUSIONS
A high intake of red meat, starchy vegetables and wine, and a moderate intake of high-sugar drinks seem to be associated with increased risk of urinary tract tumors, with differences related to the context of residence.