Dietary Patterns in Italy and the Risk of Renal Cell Carcinoma.

BACKGROUND

Conclusive evidence on foods, nutrients, or dietary patterns and the risk of renal cell carcinoma (RCC) is lacking in the literature.

METHODS

We considered data from an Italian hospital-based case-control study (1992-2004) on 767 incident RCC cases and 1534 controls. dietary patterns were identified by applying principal component factor analysis on 28 nutrients derived from a 78-item food-frequency questionnaire. We estimated the odds ratios (ORs) of RCC and corresponding 95% confidence intervals (CIs) for each quartile category (compared to the lowest one) using conditional multiple logistic regression models providing adjustment for major confounding factors.

RESULTS

We identified four dietary patterns, named "Animal products", "Starch-rich", "Vitamins and fiber", and "Cooking oils and dressings". Higher intakes of the "Starch-rich" pattern were positively associated with RCC risk (OR = 1.38, 95% CI: 1.04-1.82 for the highest quartile, = 0.018). The association was inverse with the "Cooking oils and dressings" pattern (OR = 0.61, 95% CI: 0.47-0.80, < 0.001), whereas no association was found with "Animal products" and "Vitamins and fiber" patterns.

CONCLUSIONS

Higher intakes of starch-related foods may increase RCC risk, whereas consumption of olive and seed oils may favorably influence RCC risk.