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E Riboli

Publications and source records attributed to E Riboli.

At least 145 records · Page 8Linked to original sources
PubMed1994

Adjustment for bias due to errors in exposure assessments in multicenter cohort studies on diet and cancer: a calibration approach.

An advantage of multicenter cohort studies on diet and cancer is that these may include populations over a wide range of dietary exposure. With some simplifying assumptions, the information from such multicenter studies may be divided into 1) estimated relationships within each of the separate cohorts, between individual-level measurements of dietary exposure and disease outcome, and 2) an estimated between-cohort relationship, between the mean intake measurements and mean incidence rates. Errors in the dietary exposure measurements may lead to different amounts of bias in each of these estimated relationships, in particular when dietary questionnaire methods cannot easily be standardized. A calibration approach can be used to adjust for such differences in bias. This will improve the relative weighting of within- and between-cohort components of evidence for a diet-disease association.

Cohort Studies↗
PubMed1994

Influence of methodologic factors in a pooled analysis of 13 case-control studies of colorectal cancer and dietary fiber.

We examined the study design features and data collection methods from 13 case-control studies of colorectal cancer and diet, which had been previously combined and analyzed, to determine whether they influenced the results obtained from a pooled analysis. We assessed the methods used in each study, estimated a quality score, and used random effects models to re-estimate the pooled odds ratio for the association between dietary fiber and colorectal cancer for these data. Key features of the methods used in each study and the quality score were examined in random effects models to determine whether the heterogeneity found between study-specific risk estimates could be explained by these variables. The odds ratio for dietary fiber and colorectal cancer was 0.46 (95% confidence interval = 0.34-0.64) for the 13 case-control studies as estimated with a random effects model. Two factors, whether the diet questionnaire had been validated before use in the case-control study and whether qualitative data on dietary habits and cooking methods had been incorporated into the nutrient estimation, explained some of the heterogeneity found between studies. Risk estimates for dietary fiber and colorectal cancer were closer to the null for the studies that had these two characteristics. Quality score did not explain any between-study heterogeneity. Random effects models, which included fixed effects covariates, explained some between-study heterogeneity in these data and would be useful for future pooled analyses.

Case-Control Studies↗
PubMed1994

Consumption of meat, animal products, protein, and fat and risk of breast cancer: a prospective cohort study in New York.

Epidemiologic studies have focused on the association between diet and breast cancer with conflicting results. Whereas a majority of case-control studies indicate a role for the intake of total fat and saturated fat, most prospective cohort studies either are negative or indicate very modest associations. Only a few authors have examined the role of meat intake in relation to breast cancer risk. The aim of this study was to examine the relation between risk of breast cancer and dietary intake of meat, animal products, fat, and protein. Between 1985 and 1991, we recruited 14,291 New York City women in a prospective cohort study of endogenous hormones, diet, and cancer in which they reported on their recent diet using a food frequency questionnaire self-administered at enrollment. From the cohort, 180 invasive breast cancer cases diagnosed before December 1990 and five times as many controls, individually matched by age, calendar time at enrollment, menopausal status, and, if premenopausal, phase of menstrual cycle, were included in a nested case-control study. There was an evident increase in the relative risk (RR) of breast cancer for increasing consumption of meat. Women in the upper quintile of meat consumption, as compared with the lowest quintile, had an energy-adjusted RR of 1.87 (95% confidence interval = 1.09-3.21). There was a modest RR increase in the upper quintile of total and saturated fat and no apparent association for other types of fat, protein, dairy products, poultry, or fish.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Efficient use of biological banks for biochemical epidemiology: exploratory hypothesis testing by means of a sequential t-test.

In view of recent advances in molecular and biochemical epidemiology, there is growing interest in the creation of biological banks of blood, urine, tissue, or other biological specimens collected from participants in prospective cohort studies. The existence of biological banks may make it possible to study a multitude of etiologic hypotheses, by comparing biochemical parameters measured in the biological specimens of subjects who will eventually develop the disease of interest ("cases") and of control subjects, using a nested case-control or a case-cohort design. In practice, however, the amount of biological material available per subject (in particular, that of cases) will limit the number of hypotheses that can be tested. The present paper discusses the use of a sequential t-test which, compared with an analogous fixed sample procedure, will on average require fewer biological specimens before a given study hypothesis can be accepted or rejected. The sequential test should thus facilitate an early decision on whether a new hypothesis is worth further investigation, while avoiding wasting too much biological material on testing hypotheses that may eventually prove unfruitful. If the test reveals an exposure difference of interest, the study may be extended so that relevant epidemiologic effect measures can be estimated more accurately.

Biological Specimen Banks↗
PubMed1993

Indoor air pollution and lung cancer in Guangzhou, People's Republic of China.

A case-control study comprising 224 male and 92 female incident lung cancer cases and the same number of individually matched hospital controls was conducted from June 1983 to June 1984 in Guangzhou, People's Republic of China, to evaluate the association between indoor air pollution and lung cancer risk. Guangzhou residents were exposed to several sources of pollution in their homes, most importantly to cooking fumes. Increased risks were found among subjects living in a house without a separate kitchen (the exposure odds ratio was 2.4 (95% confidence interval (CI) 1.4-4.2) for men and 5.9 (95% CI 2.1-16.0) for women). Similarly, living in a house with poor air circulation was associated with an exposure odds ratio of 2.1 (95% CI 1.2-3.8) for men and 3.6 (95% CI 1.4-9.3) for women. A trend in the association between lung cancer risk and factors pertaining to house and kitchen ventilation was observed, and a decreasing risk of lung cancer was observed for several variables indicating better ventilation, even after adjustment for potential confounders such as education, occupation, living area, smoking, and history of chronic respiratory diseases. No statistically significant differences were found between cases and controls for frequency of cooking at home, presence of a chimney in the kitchen, or type of cooking fuel. Smoking was clearly related to risk of lung cancer in both men and women, and among nonsmoking women, exposure to tobacco smoke from their spouses was also associated with an increased risk. These results suggest that, in addition to smoking, indoor air pollution may be a risk factor for lung cancer.

Adult↗
PubMed1993

Bladder cancer and coffee consumption in smokers and non-smokers in Spain.

The association between coffee consumption and bladder cancer was investigated in a multi-centre case-control study conducted in Spain from 1983 to 1986. A total of 497 cases (438 male and 59 female) with histopathologically confirmed bladder cancer were used in the analysis along with 566 hospital controls and 547 population controls. Odds ratios (OR), adjusted for age, province of residence, occupations at risk, consumption of artificial sweeteners and cigarette smoking, did not show any association between coffee consumption and bladder cancer for either sex. However, in non-smokers and mainly in males, for current coffee drinkers the OR was 2.78 (95% [Cl]: 0.78-9.87), while for drinkers of 2-7, 8-14 and > or = 15 cups/week the respective OR were 2.22, 3.11 and 1.87 with a dose-response relationship for lifelong consumption and years of exposure to regular coffee consumption. The OR in male non-smokers and current coffee drinkers were 2.36 (95% Cl: 0.62-9.05) with population controls only and 1.94, 2.58 and 1.48 for the corresponding levels of intensity of consumption (cups/week). The associations observed in non-smokers suggest the existence of a possible association between coffee consumption and bladder cancer, but are based on small numbers and need to be confirmed in larger studies.

Case-Control Studies↗
PubMed1993

Dietary assessment methods evaluated in the Malmö food study.

A study to evaluate the relative validity of two dietary assessment methods, to be used in a prospective cohort study on diet and cancer, was conducted in a random sample of the Malmö population during 1984-1985. The study compared (i) a long, self-administered 'food-use questionnaire' (about 250 food items), asking for frequency of consumption of food and beverages and for usual portion size estimated with the help of a booklet of food pictures, and (ii) a combined method involving a shorter food frequency questionnaire (about 130 food items) and a 2-week diet diary, with (iii) a reference method requiring 18 days of weighed food records. The results indicated that subject compliance was quite good for both methods and, in particular, that the diet diary was well accepted. Both methods produced fairly good correlations with the reference method, of the order of 0.40 to 0.60 for most nutrients after adjustment for energy. Both methods tended to overestimate intake of fat, protein and carbohydrates as well as of vitamins and minerals.

Aged↗
PubMed1992

Active and passive smoking and pathological indicators of lung cancer risk in an autopsy study.

OBJECTIVE: The association between involuntary smoking and lung cancer has been supported by most epidemiologic studies, but a number of authors and interest groups claim that the possibility of bias has not been excluded. Few autopsy-based studies have explored the role of active smoking and other exposures in lung carcinogenesis, and none has been previously done to examine the role of passive smoking. We have undertaken such an autopsy-based study in Athens, Greece. DESIGN: Lung specimens were taken at autopsy from 400 persons 35 years of age or older, of both genders, who had died within 4 hours from a cause other than respiratory or cancer in Athens or the surrounding area. For each person at least seven tissue blocks were taken from the main and lobar bronchi and at least five blocks from the parenchyma, including an average of about 20 smaller cartilaginous bronchi and membranous bronchioles. The specimens were examined without knowledge of the exposures of the particular subject in Turin, Italy. For 283 (71%) of the subjects the preservation of the bronchial epithelium was satisfactory for pathological examination, and for 206 among them (73%) an interview could be arranged with their next of kin, focusing on smoking habits of the deceased and their spouses, as well as other variables. The interviewers were not aware of the results of the pathological examinations. MAIN OUTCOME MEASURE: Specimens were examined for basal cell hyperplasia, squamous cell metaplasia, cell atypia, and (in membranous bronchioles and bronchiolo-alveolar airways) mucous cell metaplasia, ie, pathological entities that may be lung cancer risk indicators or epithelial, possibly precancerous, lesions (EPPL). The gland and wall thicknesses were also measured and their ratio calculated (Reid Index). RESULTS: In comparison with nonsmokers, EPPL values were significantly higher among current smokers and higher, but not significantly so, among former smokers. Furthermore, EPPL values were significantly higher among deceased nonsmoking women married to smokers rather than to nonsmokers. In this set of data neither occupation nor residence was associated with EPPL, but this could be due to the poor correlation of residential history with exposure to air pollution and the lack of adequate standardization of contemporary Greek occupations. The Reid Index was higher among smokers and former smokers in comparison with nonsmokers, among subjects with mainly urban residence in comparison with those with mainly rural residence, and among nonsmoking women married to smokers in comparison with those married to nonsmokers, but none of these differences was statistically significant. CONCLUSION: These results provide support to the body of evidence linking passive smoking to lung cancer, even though they are based on a study methodologically different from those that have previously examined this association.

Adult↗
PubMed1992

Dietary habits, internal migration and social class in a sample of a northern Italian population.

The study of migrants has generated interesting hypotheses on the etiology of different types of cancer. In particular, it has been suggested that both colon and breast cancer could be related to living conditions, including diet, in the country of immigration. Considerable internal migration occurred in Italy in the sixties. We studied a random sample of 1,400 subjects living in the city of Torino and the province of Varese. They were interviewed with a detailed questionnaire about their dietary habits, and the consumption of several nutrients was considered according to the area of birth and social class. The hypothesis we tested was whether, after controlling for social class, there were different dietary habits among the migrants and the native population, and whether such differences could help in the formulation of etiologic hypotheses on cancer. We found that the intake of saturated fatty acids and cholesterol was lower among the migrants from the south, whereas they consumed higher levels of vegetables than people born in the north. The different intake of saturated fatty acids and cholesterol seemed to be attributable mainly to the consumption of butter, for which the south/north ratio was as low as 0.47 in men and 0.56 in women. Important gradients by social class were also suggested for several nutrients.

Adult↗
PubMed1992

Diet and gastric cancer. A case-control study in Belgium.

A case-control study was carried out in 2 Belgian provinces with contrasting gastric-cancer mortality. The results were analyzed for the total study group and also separately in each of the 4 sub-groups: men and women in each province. Only risks which appeared consistently in at least 3 of these 4 sub-groups were retained in the discussion. Consumption of most vegetables, either cooked or raw, and of fresh fruit was found to be protective. There was an increased risk associated with meal and flour products, including white bread. Added sugar also increased the risk of gastric cancer. Consumption of lean meat was associated with a decreased risk. There was no clear effect for most sources of fat, but for oils with a high P/S ratio there was a decreased risk. Together with our earlier finding on salt, these results are to a large extent similar to those of other recent studies on gastric cancer.

Adult↗
PubMed1992

Nutrition and cancer: background and rationale of the European Prospective Investigation into Cancer and Nutrition (EPIC).

The development of epidemiological research on diet and cancer during the last decades is discussed. Apart from some consistent data on the protection against several cancers conferred by a diet rich in fruits and vegetables, the results provided by retrospective case-control studies on diet and cancer remain contradictory on many important issues, and primarily on the relation between diet and breast cancer. The rationale is presented for setting up large prospective cohort studies combining epidemiological and laboratory methods in order to expand the presently limited knowledge of the role of nutrition and related factors in cancer etiology. The main features of the European Prospective Investigation into Cancer and Nutrition are outlined. The study is being carried out in seven European countries and it will collect data on diet, other lifestyle and environmental factors, anthropometry as well as biological samples in a cohort of about 400,000 healthy European adults. The subjects will be followed up to investigate the incidence of and mortality from cancer in relation to epidemiological data and biochemical markers.

Cohort Studies↗
PubMed1992

Validation of a method for the estimation of food portion size.

In the context of the planning phase of a large cohort study on dietary habits and cancer, we have developed a food frequency questionnaire on usual food intake, which includes a set of pictures to estimate the portion size of 23 different dishes. The validity of the estimation of portion size of recently consumed foods has been questioned by other researchers. To validate the use of pictures, we organized a field trial with 103 volunteers. They were invited to a dinner where standard Italian dishes were offered (total 17 foods); all of the portions they chose were recorded and weighed. The following day, we interviewed the volunteers on what they consumed during the dinner, and we compared the weight of the food actually eaten with the weight of the food represented in the pictures. The volunteers overestimated the portion size by more than 20% for six foods and underestimated the portion size by more than 20% for four foods. In addition, we found a tendency toward overestimation of portion size by those who ate smaller portions and underestimation, by those who ate larger portions ("flat slope syndrome").

Adult↗
PubMed1991

Dietary factors and stomach cancer in Spain: a multi-centre case-control study.

A multi-centre case-control study of diet and gastric cancer was carried out in 4 regions of Spain (Aragon, Castile, Catalonia and Galicia). We selected 354 cases of pathologically confirmed gastric adenocarcinoma from 15 hospitals, representative of nearly all those in the study areas. A control for each case, matched by age, sex and area of residence, was selected from the same hospital as the case. Habitual diet was investigated by the dietary history method, and past diet by means of a frequency questionnaire. The results regarding consumption of food items are presented here. With respect to habitual diet, an increase in risk was associated with consumption of preserved fish, cold cuts and oleaginous fruits. A high intake of cooked green vegetables, fresh noncitrus fruit and dried fruit showed an inverse association with the risk of gastric cancer. Simultaneous intake of 2 groups of food which increase or decrease the risk of cancer strengthens the respective individual effect. The intake of protective food items seems to neutralize the effects of food items which increase risk. With reference to past diet, a possible protective effect was observed for daily consumption of fresh fruit and green vegetables.

Adenocarcinoma↗
PubMed1991

Tobacco smoke inhalation pattern, tobacco type, and bladder cancer in Spain.

The association between tobacco smoking and bladder cancer was investigated in a multicenter case-control study conducted in five provinces of Spain between 1983 and 1986. A matched analysis was carried out in males, based on 430 histologically confirmed cases, 405 hospital controls, and 386 population controls, matched by age and place of residence. An increased risk was found for smokers as compared with nonsmokers (odds ratio (OR) = 3.79, 95% confidence intervals (CI) 2.41-5.97), and this increase was significantly associated with the intensity of smoking. Smokers of filter-tipped cigarettes had a reduced risk as compared with smokers of non-filter-tipped cigarettes (OR = 0.57, 95% CI 0.32-1.02). A diminution of risk was also observed for smokers of low-tar and low-nicotine ("light") cigarettes. Depth of inhalation was strongly associated with illness. No difference was shown in the logistic regression model between smokers of black tobacco and smokers of blond tobacco after controlling for depth of inhalation. Although the number of persons who smoked blond tobacco exclusively was small, the results suggest that it is important to consider inhalation patterns when studying risk variations between smokers of black tobacco and smokers of blond tobacco. The age at which a person started to smoke did not appear to affect risk. An analysis of the decrease in risk associated with years since quitting smoking suggested that different components of cigarette smoke may play a role at different stages of the carcinogenic process.

Female↗
PubMed1991

Diet and bladder cancer in Spain: a multi-centre case-control study.

A multi-centre case-control study on bladder cancer and diet was carried out in 5 regions of Spain. We report results on 432 male cases and 792 matched controls. Usual dietary habits were investigated by means of an interview-based dietary history questionnaire. Bladder-cancer cases were selected from the registers of 12 hospitals located in the study areas. Each case was matched by sex, age and area of residence to 2 controls, one identified in the same hospital and one drawn from population lists. Descriptive analyses indicated that the average dietary pattern was typical of Mediterranean populations: a high P/S ratio, high intake of fish, fruits and vegetables and moderate or low intake of meat and dairy products. Relative risks for specific foods and nutrients were adjusted for tobacco smoking and energy intake. Subjects in the highest quarter of intake of saturated fat had a significantly increased risk of bladder cancer (RR for highest quarter = 2.25; 95% CI = 1.42 to 3.55). Moderate increases in risk for high intake of mono-unsaturated fats and calcium, and a slight decrease for iron were also found, but these disappeared after adjustment for saturated fat. Intake of vitamin E was related to slightly reduced risk (RR for highest quarter = 0.72; 95% CI = 0.48 to 1.09) which was not modified by adjustment for fat. No association was found with intake of retinol or carotene. These results, along with those of previous studies, suggest that saturated fat intake may influence the occurrence of bladder cancer.

Calcium↗