No abstract

To estimate the effects of consuming hot beverages, including mate (an infusion of the herb Ilex paraguayensis), tea, coffee and coffee with milk, and other food items on esophageal cancer risk, we analyzed data from 830 cases and 1,779 controls participating in a series of 5 hospital‐based case‐control studies of squamous‐cell carcinoma of the esophagus conducted in high‐risk areas of South America. After adjusting for the strong effects of tobacco and alcohol consumption, both heavy mate drinking (>1 l/day) and self‐reported very hot mate drinking were significantly associated with esophageal cancer risk in men and women. The magnitude and strength of the association for mate amount and, to a lesser extent, mate temperature were higher for women than men. The joint effects of mate amount and mate temperature were more than multiplicative, following a statistically significant synergistic interaction (p = 0.02) which was particularly evident among heavy drinkers (>1.50 l/day) of very hot mate (odds ratio = 4.14, 95% confidence interval: 2.24–7.67) compared to light drinkers (<0.50 l/day) of cold/warm/hot mate. Consumption of other very hot beverages, such as tea and coffee with milk but not coffee alone, was also significantly associated with an increased risk, in the 2‐ to 4‐fold range. Statistically significant protective associations were identified for high consumption of vegetables, fruits, cereals and tea. In contrast, frequent consumption of meat, animal fats and salt was associated with a moderately increased risk. This pooled analysis adds evidence for a carcinogenic effect of chronic thermal injury in the esophagus induced by the consumption of very hot drinks, including mate. Our study further confirms the protective effect of a dietary pattern characterized by daily consumption of fruits and vegetables and low consumption of meat and animal fats. Int. J. Cancer 88:658–664, 2000. © 2000 Wiley‐Liss, Inc.

A multisite case-control study on factor analysis and several cancer sites (mouth and pharynx, esophagus, stomach, colon, rectum, larynx, lung, breast, prostate, bladder, kidney) was conducted in Uruguay. The study included 3,528 cases and 2,532 controls. Factor analysis (principal components) was modeled among controls. This patterning method retained 4 factors per sex, labeled as prudent, drinker, traditional and Western. Odds ratios for these cancer sites, stratified by sex, were estimated using polytomous regression. Whereas the prudent pattern was mainly negatively associated with cancers of the upper aerodigestive tract, the Western pattern showed a strong increase in breast, lung and colon cancers. The study allowed for the reproducibility of the prudent, drinker and Western patterns, whereas the traditional pattern appears to be country specific. ' 2008 Wiley-Liss, Inc.Key words: dietary patterns; factor analysis; principal components; polytomous regression Uruguay is a developing country with high rates of cancer, showing age-adjusted incidence rates of 386.0 per 100,000 men and 303.2 per 100,000 women for all sites. 1 The most frequent sites are female breast (age standardized rate 114.9 per 100,000 women) and lung (Age standardized rate 76.5 per 100,000 men). Smoking and alcohol drinking are the major risk factors for frequent cancers like lung cancer and cancers of the upper aerodigestive tract in the Uruguayan population. Also, a diet low in vegetables and fruits and high in beef consumption are risk factors for digestive tract cancers. 2 Since foods are consumed together it could be suggested that the true effect of the diet may only be observed when all components are analyzed simultaneously. In fact, foods could act in synergism or be metabolized jointly. [3][4][5] Patterning methodologies, including factor analysis, may turn the analytical difficulties into an advantage. Factor analysis is used to reduce a large number of foods or nutrients to smaller number of factors for modeling purposes. 6 This analytic method was originated in the pioneer paper of Spearman in 1904. 7 Since then it has grown explosively mainly in psychology and social sciences. In 1992, Randall et al. 8 firstly applied this method in the study of food patterns and colon cancer. Since then, numerous studies on dietary patterns and diverse cancers have been published all over the World.On the basis of a large dataset of cases and controls, we decided to conduct a multisite study using factor analysis in a high-risk country such as Uruguay. The main objective was to estimate odds ratios (ORs) of several cancer sites by means of the application of the principal components method and multinomial regression. Material and methodsA large scale study was designed jointly by the

To generate broad eating patterns, which could explain more adequately the breast cancer etiology, we conducted an exploratory factor analysis in Montevideo, Uruguay. The study included 442 newly diagnosed and microscopically confirmed cases with breast cancer and 442 hospitalized controls, with non-neoplastic diseases. Factor analysis (principal components) was conducted in the control series, and as a result, 6 factors were extracted. These factors were labeled as traditional, healthy, western, stew, high-fat and drinker. The model explained 58.3% of the variance. After scoring the rotated factors, the relations between scores and breast cancer risk factors were analyzed by using Pearson correlation coefficients. After this step, the odds ratios of breast cancer for continuous scores of the rotated factors were carefully analyzed. The highest risk was directly associated with the western diet (OR 1.31, 95% CI 1.13-1.51), whereas the traditional (OR 0.77, 95% CI 0.64-0.93), healthy (OR 0.84, 95% CI 0.73-0.98) and stew (OR 0.83, 95% CI 0.71-0.98) diets were significantly protective. Women who reported a history of breast cancer among mother and sisters displayed strong elevations in risk for western (OR 2.03, 95% CI 1.11-3.72) and high-fat (OR 2.72, 95%CI 1.16-6.37) dietary patterns. This finding could suggest that gene-dietary interaction could play an important role in breast carcinogenesis. ' 2006 Wiley-Liss, Inc.