Maté drinking and esophageal squamous cell carcinoma in South America: pooled results from two large multicenter case-control studies.

BACKGROUND: Maté tea is a nonalcoholic infusion widely consumed in southern South America, and may increase risk of esophageal squamous cell carcinoma (ESCC) and other cancers due to polycyclic aromatic hydrocarbons (PAH) and/or thermal injury. METHODS: We pooled two case-control studies: a 1988 to 2005 Uruguay study and a 1986 to 1992 multinational study in Argentina, Brazil, Paraguay, and Uruguay, including 1,400 cases and 3,229 controls. We computed ORs and fitted a linear excess OR (EOR) model for cumulative maté consumption in liters/day-year (LPDY). RESULTS: The adjusted OR for ESCC with 95% confidence interval (CI) by ever compared with never use of maté was 1.60 (1.2-2.2). ORs increased linearly with LPDY (test of nonlinearity; P = 0.69). The estimate of slope (EOR/LPDY) was 0.009 (0.005-0.014) and did not vary with daily intake, indicating maté intensity did not influence the strength of association. EOR/LPDY estimates for consumption at warm, hot, and very hot beverage temperatures were 0.004 (-0.002-0.013), 0.007 (0.003-0.013), and 0.016 (0.009-0.027), respectively, and differed significantly (P < 0.01). EOR/LPDY estimates were increased in younger (<65) individuals and never alcohol drinkers, but these evaluations were post hoc, and were homogeneous by sex. CONCLUSIONS: ORs for ESCC increased linearly with cumulative maté consumption and were unrelated to intensity, so greater daily consumption for shorter duration or lesser daily consumption for longer duration resulted in comparable ORs. The strength of association increased with higher maté temperatures. IMPACT: Increased understanding of cancer risks with maté consumption enhances the understanding of the public health consequences given its purported health benefits.

Nutrient patterns and risk of breast cancer in Uruguay.

OBJECTIVES: To explore the role of nutrient patterns in the etiology of breast cancer (BC) among Uruguayan women. METHODS: A principal component analysis was conducted. The study included 442 newly diagnosed cases of BC and 442 hospitalized controls. RESULTS: Two dietary patterns derived from factor analysis and were labeled as high-meat and antioxidants patterns. Whereas the high-meat pattern was directly associated with BC risk (OR for the highest versus the lowest quartile = 3.50, 95 % CI 1.94-6.30, p-value for trend <0.0001), the antioxidants pattern displayed a protective effect (OR=0.44, 95 % CI 0.27-0.74). Its negative association was stronger for postmenopausal than for premenopausal women (OR=0.63, 95% CI 0.51-0.79 vs. OR=0.89, 95% CI 0.50-1.56, respectively). Both strata were heterogeneous (p=0.004). The high-meat pattern was more associated with BC risk among patients with family history of BC compared with participants without it, but results did not differ by histology. In contrast, the antioxidants pattern was more associated with non-ductal cancers (OR=0.50 [95 % CI 0.35-0.69]) than with ductal cancers (OR=0.72, 95 % CI 0.58-0.88, heterogeneity p-value=0.03). CONCLUSIONS: Results support an association between the high-meat and antioxidant dietary patterns and BC risk. Furthermore, findings suggest that gene-environmental interactions may be important in BC etiology.

Hormonal and metabolic modulation through nutrition: towards a primary prevention of breast cancer.

Breast cancer (BC) is a polygenic and multifactorial disease for which estrogens have been recognized as the main risk factor, and for which lifestyle plays a key role. Previous epidemiologic cancer research performed in Uruguayan population delimited its dietary and anthropometric profiles. Recognizing the difficulty for universalizing a nutritional basis for prevention due to different eating patterns among regions and countries, we summarize the existent knowledge linking nutrition, estrogens, metabolism and BC. As an attempt towards primary prevention of BC, we present recommendations mainly based on country-specific research findings and modifiable putative risk and protective factors, proposing to modify the intake of meats and other fatty foods--especially sources of Ω-6 and Ω-3 fatty acids--adding olive oil, selected vegetables, citrus fruits and working towards adequate body fat/muscle proportions. From a medical and ethical viewpoint, it is justified to recommend certain nutritional changes to women, because no adverse side effects are expected to occur.

Dietary patterns and risk of bladder cancer: a factor analysis in Uruguay.

OBJECTIVE: To determine the major dietary patterns associated with bladder cancer risk, we conducted a principal components analysis (PCA) in a case-control study from Uruguay. METHODS: A total of 255 newly diagnosed and microscopically confirmed cases of transitional cell carcinoma of the bladder and 501 hospitalized controls were included in the study. Both series were drawn from the four major public hospitals in Montevideo, Uruguay. Cases and controls were frequency matched on age and sex. Controls were submitted to factor (principal components) analysis. RESULTS: We retained three factors that explained 25.1% of the total variance (including error variance). The first factor was labeled as the sweet beverages pattern. This factor was characterized by high loadings of coffee, tea, and added sugar and was strongly associated with risk of bladder cancer (OR 3.27, 95% CI 1.96-5.45). The second factor was labeled as the Western pattern and displayed high loadings of red meat, fried eggs, potatoes, and red wine. This pattern was directly associated with risk of bladder cancer (OR 2.35, 95% CI 1.42-3.89). Finally, the third factor was labeled as the prudent pattern and showed high loadings of fresh vegetables, cooked vegetables, and fruits. This pattern was not associated with risk of bladder cancer. CONCLUSIONS: According to our study, non-alcoholic beverages were the strongest risk factor for bladder cancer, whereas the Western pattern was also associated with a significant increase in risk of bladder cancer.

Non-alcoholic beverages and risk of bladder cancer in Uruguay.

BACKGROUND: Bladder cancer is the fourth most frequent malignancy among Uruguayan men. A previous study from Uruguay suggested a high risk of bladder cancer associated with maté drinking. We conducted an additional case-control study in order to further explore the role of non-alcoholic beverages in bladder carcinogenesis. METHODS: In the time period 1996-2000, 255 incident cases with transitional cell carcinoma of the bladder and 501 patients treated in the same hospitals and in the same time period were frequency matched on age, sex, and residence. Both cases and controls were face-to-face interviewed on occupation, tobacco smoking, alcohol drinking and intake of maté, coffee, tea, and soft drinks. Statistical analysis was carried out by unconditional multiple logistic regression. RESULTS: Ever maté drinking was positively associated with bladder cancer (odds ratio [OR] 2.2, 95% confidence interval [CI] 1.2-3.9) and the risk increased for increasing duration and amount of maté drinking. Both coffee and tea were strongly associated with bladder cancer risk (OR for coffee drinking 1.6, 95% CI 1.2-2.3; OR for tea drinking 2.3, 95% CI 1.5-3.4). These results were confirmed in a separate analysis of never-smokers. CONCLUSION: Our results suggest that drinking of maté, coffee and tea may be risk factors for bladder carcinoma in Uruguay.

Maté consumption and the risk of squamous cell esophageal cancer in uruguay.

A retrospective hospital-based case-control study was carried out at the Oncology Institute of Montevideo, Uruguay, to investigate the role of maté consumption in esophageal cancer risk. The study included 344 cases with squamous cell carcinoma of the esophagus and 469 controls recruited between January 1988 and August 2000. Maté consumption was significantly associated with an increased risk of developing esophageal cancer and showed a clear dose response, with a relative risk of 2.84 [95% confidence interval (CI), 1.41-5.73] for those drinking more than 1 liter/day of maté as compared with nondrinkers. Subjects who self-reported drinking maté at a very hot temperature had an almost 2-fold increase in risk [odds ratio (OR), 1.87; 95% CI, 1.17-3.00] compared with those drinking warm to hot maté, after adjusting for cumulative consumption of maté. Maté amount and temperature were observed to have independent effects and, although no departure from multiplicativity was observed between the two covariates, those drinking more than 1 liter/day of maté at a very hot temperature had a 3-fold increase in risk (OR, 2.95; 95% CI, 1.30-6.74) compared with those drinking less than 0.5 liter/day of maté at a warm to hot temperature. Subjects with high cumulative exposure to maté in the presence of low alcohol and tobacco exposures presented a lower-risk estimate (OR, 1.52; 95% CI, 0.88-2.62), whereas those with high cumulative exposures to maté, alcohol, and tobacco presented a 7-fold increase in esophageal cancer risk (OR, 7.10; 95% CI, 3.75-13.46). The population-attributable fraction as a result of maté consumption was calculated to be 53%, of which the sole effect of amount and temperature was 14.8 and 12.6% respectively, and 14.9% was attributable to high maté consumption at high temperature.