Biomedical subjects

E Riboli

Publications and source records attributed to E Riboli.

At least 109 records · Page 6Linked to original sources

PubMed1999

High intake of specific carotenoids and flavonoids does not reduce the risk of bladder cancer.

An analysis of a previously completed Spanish multicentric case-control study of bladder cancer was carried out using new available data on the contents in foods of specific carotenoids (alpha-carotene, beta-carotene, lutein, and lycopene) and flavonoids (quercetin, kaempferol, myricetin, and luteolin) to investigate the relationship of these phytochemicals with bladder cancer. The study included 497 cases first diagnosed with bladder cancer, 547 neighborhood controls, and 566 hospitals controls, matched by gender, age, area of residence, and hospital. Usual food intake was estimated using a dietary history questionnaire administered by trained interviewers. None of the specific carotenoids and none of the specific flavonoids have been found to be significantly associated with bladder cancer risk in this analysis. The adjusted odds ratios for subjects in the highest quartile of intake with respect to subjects in the lowest quartile were 1.36 (95% confidence interval = 0.94-1.95) for total carotenoid intake and 1.23 (95% confidence interval = 0.85-1.79) for total flavonoid intake. The results of this study does not support the hypothesis that intake of specific carotenoids and flavonoids is protective against bladder cancer risk.

Carotenoids↗

PubMed1998

Nutrient intake patterns and gastric cancer risk: a case-control study in Belgium.

A case-control study on gastric cancer risk in relation to nutrient composition of diet was conducted in the 2 Belgian provinces of Oost-Vlaanderen and Liège as part of a large epidemiological study on cancers of the digestive tract, also including colorectal cancer. The statistical analysis was carried out on a total of 301 men and women aged 35-74 years with histologically confirmed stomach tumors and 2,851 population controls. Dietary intake assessments were obtained by interview, using a dietary history questionnaire. Gastric cancer risk was increased for diets rich in mono- and disaccharides, according to statistical models based on energy-adjusted residuals [odds ratio (OR) = 1.88 for upper vs. lower quartiles of energy-adjusted intakes] or energy decomposition models, but showed no increase for high intake of polysaccharides. Intake of polyunsaturated fats, particularly linoleic acid, was inversely associated with gastric cancer risk. High intake of vitamin C, beta carotene and vitamins B1 (thiamine), B3 (nicotinic acid) or B6 (pyridoxine) was also associated with decreased risk, whereas increased risk was observed for high intake of vitamin A (retinol) or vitamin B2 (riboflavin). Many of these associations between gastric cancer risk and nutrient composition were similar to those found in the analysis of a parallel study on cancers of the colon and rectum.

Adult↗

PubMed1998

Multicenter case-control study of exposure to environmental tobacco smoke and lung cancer in Europe.

BACKGROUND: An association between exposure to environmental tobacco smoke (ETS) and lung cancer risk has been suggested. To evaluate this possible association better, researchers need more precise estimates of risk, the relative contribution of different sources of ETS, and the effect of ETS exposure on different histologic types of lung cancer. To address these issues, we have conducted a case-control study of lung cancer and exposure to ETS in 12 centers from seven European countries. METHODS: A total of 650 patients with lung cancer and 1542 control subjects up to 74 years of age were interviewed about exposure to ETS. Neither case subjects nor control subjects had smoked more than 400 cigarettes in their lifetime. RESULTS: ETS exposure during childhood was not associated with an increased risk of lung cancer (odds ratio [OR] for ever exposure = 0.78; 95% confidence interval [CI] = 0.64-0.96). The OR for ever exposure to spousal ETS was 1.16 (95% CI = 0.93-1.44). No clear dose-response relationship could be demonstrated for cumulative spousal ETS exposure. The OR for ever exposure to workplace ETS was 1.17 (95% CI = 0.94-1.45), with possible evidence of increasing risk for increasing duration of exposure. No increase in risk was detected in subjects whose exposure to spousal or workplace ETS ended more than 15 years earlier. Ever exposure to ETS from other sources was not associated with lung cancer risk. Risks from combined exposure to spousal and workplace ETS were higher for squamous cell carcinoma and small-cell carcinoma than for adenocarcinoma, but the differences were not statistically significant. CONCLUSIONS: Our results indicate no association between childhood exposure to ETS and lung cancer risk. We did find weak evidence of a dose-response relationship between risk of lung cancer and exposure to spousal and workplace ETS. There was no detectable risk after cessation of exposure.

Aged↗

PubMed1998

Breast-cancer incidence in relation to height, weight and body-fat distribution in the Dutch "DOM" cohort.

In a cohort of 11,663 participants in a breast-cancer screening program, height, weight, waist circumference and hip circumference were measured, and information about menstrual and reproductive history was obtained by questionnaire. After exclusion of 83 women with unclear menopausal status, the subjects were divided into 3 sub-cohorts: 5,891 women who were pre-menopausal at the time of data collection, 3,521 women who had entered the study after natural menopause, and 2068 women who had been hysterectomized and/or ovariectomized. After a median follow-up of 10.6 years, 147, 76 and 52 incident cases of breast cancer were detected in the 3 respective sub-cohorts. No statistically significant association was found in any of the sub-cohorts between breast-cancer risk and height, weight, body-mass index (BMI) or hip circumference. In the sub-cohort of women with natural menopause, however, risk of breast cancer was positively and significantly associated with the ratio of waist-to-hip circumferences (WHR) (RR = 2.63 for upper vs. lower quartile), and this association did not change after adjustment for variations in disease risk related to body height and weight. Although similar to observations in other cohort studies showing positive associations between obesity and breast-cancer risk in post-menopausal women, our results are different, in that WHR and not BMI appears to be the more specific indicator of breast-cancer risk.

Adipose Tissue↗

PubMed1998

[EPIC-SOFT a European computer program for 24-hour dietary protocols].

Within the EPIC study (European Prospective Investigation into Cancer and Nutrition) a calibration approach is applied to compare dietary data obtained by food frequency questionnaires from 9 European countries. A software for 24-h recalls was developed as the calibration instrument by the International Agency for Research on Cancer (IARC) in collaboration with all national EPIC centers. This computer program, called EPIC-SOFT, is an interview-based dietary assessment instrument that allows one to obtain a very detailed description and quantification of foods, recipes, and supplements consumed in the course of the preceding day. Probing questions and entering consumed foods in chronological order support the respondent's memory. The standardized structure prescribes--on the food group level--possibilities of description and quantification of food items to choose from. Quantification of consumed foods is supported by the EPIC-SOFT picture book that comprises colored photographs of foods in different portion sizes. The software provides an automatic coding of food items and recipe ingredients as well as calculation of nutrient intake. EPIC-SOFT is characterized by the obtained standardization of dietary data within Europe, a large number of available foods and recipes, and a very detailed description of consumed foods. Currently, EPIC-SOFT is one of the few dietary instruments providing comparable nutritional data within Europe.

Calibration↗

PubMed1998

Intake of specific carotenoids and flavonoids and the risk of lung cancer in women in Barcelona, Spain.

Newly available data of a case-control study of lung cancer in women in Spain were analyzed to assess the relationship with the intake of specific carotenoids (alpha-carotene, beta-carotene, lutein, and lycopene) and flavonoids (quercetin, kaempferol, myricetin, and luteolin). The study included 103 cases and 206 hospital controls, matched by age and residence. Usual food intake was estimated through a food-frequency questionnaire. With adjustment for smoking habit and vitamin E, vitamin C, and total flavonoid intake, no association was found for the intake of alpha-carotene, beta-carotene, or lutein. The odds ratio (95% confidence interval) for women in the highest tertile of lycopene intake with respect to the lowest was 0.56 (0.26-1.24), with p for trend = 0.15. A nonsignificant association was observed for the highest vs. lowest tertile intake of kaempferol (odds ratio = 0.51, 95% confidence interval = 0.22-1.17), with p for trend = 0.10, after adjustment for smoking and vitamin E, vitamin C, and total carotenoid intake. No protective effect was observed for quercetin or luteolin or for total flavonoid intake.

Carotenoids↗

PubMed1997

Simultaneous measurement of seven carotenoids, retinol and alpha-tocopherol in serum by high-performance liquid chromatography.

A reversed-phase high-performance liquid chromatography (HPLC) procedure for the quantitative measurement in serum of seven carotenoids (lutein, zeaxanthin, canthaxanthin, beta-cryptoxanthin, lycopenes, alpha-carotene and beta-carotene), retinol, alpha-tocopherol and two internal standards (tocol and echinenone) has been developed. The geometric isomers, lutein and zeaxanthin, were completely separated as well as at least nine unidentified carotenoids. All compounds were resolved on an Adsorbosphere HS C18 (3 microm) column (250x4.6 mm I.D.) with a step gradient, 7.1 min after injection, from acetonitrile-methanol (60:40, v/v) containing 0.05% acetic acid to acetonitrile-methanol-dichloromethane (45.6:30.4:24, v/v) containing 0.04% acetic acid, in a total run time of 23 min. Chromatograms at four different wavelengths (292, 325, 450 and 473 nm) and spectra were monitored with a diode array detector. Because of its specificity and sensitivity for a large number of carotenoids, this procedure may be of interest for nutritional and epidemiological studies. Its speed and robustness make it suitable for analyses on large numbers of subjects.

Adult↗

PubMed1997

The role of multi-centre cohort studies in studying the relation between diet and cancer.

In spite of important progress made during recent decades in nutritional epidemiology methods, many questions about the role of diet in determining cancer risk remain elusive. One example of an unresolved question is whether a high percentage of energy intake in the form of fat (especially saturated fat) is associated with an increased risk of breast cancer. Observations from international correlation and case-control studies support this hypothesis, while results from prospective cohort studies, generally considered less prone to bias, do not. In this paper, we review the advantages and limitations of these different types of epidemiological study design, and discuss how multi-centre studies may help answer some of the unresolved questions about relations between diet, nutritional status, and cancer risk. Multi-centre cohort studies may have the advantage of increased statistical power because of larger variations in individuals' dietary intake patterns and disease risk (as in international correlation studies), while at the same time offering all the possibilities of individual-level studies to model confounding and/or interaction effects.

Case-Control Studies↗

PubMed1997

Estrogenic effect of DDT in CBA female mice.

Dichlorodiphenyltrichloroethane (DDT) administered to CBA female mice provoked a significant uterine weight increase and pseudoestrus comparable to that produced by diethylstilbestrol (DES) used in a positive control.

Administration, Oral↗

PubMed1997

The relationship between dietary fat intake and risk of colorectal cancer: evidence from the combined analysis of 13 case-control studies.

The objective of this study was to examine the effects of the intake of dietary fat upon colorectal cancer risk in a combined analysis of data from 13 case-control studies previously conducted in populations with differing colorectal cancer rates and dietary practices. Original data records for 5,287 cases of colorectal cancer and 10,470 controls were combined. Logistic regression analysis was used to estimate odds ratios (OR) for intakes of total energy, total fat and its components, and cholesterol. Positive associations with energy intake were observed for 11 of the 13 studies. However, there was little, if any, evidence of any energy-independent effect of either total fat with ORs of 1.00, 0.95, 1.01, 1.02, and 0.92 for quintiles of residuals of total fat intake (P trend = 0.67) or for saturated fat with ORs of 1.00, 1.08, 1.06, 1.21, and 1.06 (P trend = 0.39). The analysis suggests that, among these case-control studies, there is no energy-independent association between dietary fat intake and risk of colorectal cancer. It also suggests that simple substitution of fat by other sources of calories is unlikely to reduce meaningfully the risk of colorectal cancer.

Adult↗

PubMed1997

Reproducibility of a food frequency questionnaire used in the New York University Women's Health Study: effect of self-selection by study subjects.

OBJECTIVE: The aim of the study was to investigate the reproducibility of a food frequency questionnaire (FFQ) used in a cohort of 14,290 women enrolled in the NYU Women's Health Study. DESIGN: A subset of 474 cohort subjects who completed the dietary questionnaire at baseline (FFQ-1) were approached again on the occasion of a second visit to the mammography study centre and asked to complete the questionnaire a second time (FFQ-2) two to four years after FFQ-1. Two to three months later the questionnaire was mailed to the subjects, and they were asked to complete it a third time (FFQ-3). SETTING: A breast cancer screening clinic. SUBJECTS: Of the 474 subjects selected, 100% completed the second questionnaire while only 56% completed and mailed back FFQ-3. This made it possible to compare the long-term reproducibility of dietary intake measurements and baseline dietary habits between the two groups of subjects 'respondents', who agreed to complete the questionnaire a third time, and 'non-respondents', who did not. RESULTS: Among respondents (56% of study subjects), energy-adjusted correlation coefficients for short-term reproducibility between FFQ-2 and FFQ-3 ranged from 0.50-0.64 for nutrients, and from 0.44-0.67 for foods. The long-term reproducibility was lower, ranging from 0.36-0.53 for nutrients, and from 0.31-0.48 for specific food groups. Among those who did not respond to FFQ-3, crude correlations for long-term reproducibility, unadjusted for energy intake, were generally lower than among respondents. Nevertheless, after adjustment for energy intake, correlations for long-term reproducibility (FFQ-2 to FFQ-1) were of similar magnitude in both groups. In addition, 'non-respondents' reported lower intake of fruit and vegetables and higher intake of meat. CONCLUSIONS: The results of this study suggest that subjects who volunteer to participate in substudies on the validity or reproducibility of dietary questionnaire measurements may tend to provide more accurate responses to the questionnaire. The phenomenon seems related more to accuracy of reporting of absolute intake levels than of the relative composition of diet, self-selection may be associated with differences in dietary habits.

Adult↗

PubMed1997

Prospective study of diet and female colorectal cancer: the New York University Women's Health Study.

The relation between diet and female colorectal cancer was analyzed in a prospective study of 14,727 women aged 34-65 years, who were enrolled at mammographic screening clinics in New York and Florida from 1985 to 1991. They were followed through the end of 1994 (average 7.1 yrs) by a combination of direct contact through mail and telephone and record linkages with regional tumor registries, resulting in 100 incident cases of colorectal cancer. There was no overall positive or inverse association of colorectal cancer risk with intakes of total calories, total or subclasses of fat, carbohydrate, or dietary fiber, whereas there was an inverse association with total protein. Among major food groups, there was a progressive decline in risk of colorectal cancer with increasing intake of fish and shellfish (relative risk for 4th vs. 1st quartile = 0.49, 95% confidence interval = 0.27-0.89). A similar inverse association was also observed for consumption of dairy products, and this association was explained mainly by calcium, not by other nutrients, such as fat or protein. The results of the present study indicated that certain dietary components of fish or dairy products may protect against colorectal cancer, whereas the relations with red meat or total fat remained unclear.

Adult↗

PubMed1997

Validation and calibration of dietary intake measurements in the EPIC project: methodological considerations. European Prospective Investigation into Cancer and Nutrition.

The statistical power of prospective studies on diet in relation to chronic disease risk can be improved by maximizing the variation in true intake levels actually distinguished--or 'predicted'--by dietary questionnaire assessments collected at baseline. This can be achieved by 1) developing a questionnaire method that provides measurements with the smallest possible random errors, thus maximizing the correlation of measured with true habitual intake levels; and 2) increasing the between-person variation in true dietary intake levels when combining multiple cohorts in populations with diverse consumption patterns. The first approach implies that, during the development or selection of the questionnaire method, correlations between measurements and true intake levels can be monitored; the second approach requires adjustment for between-centre differences in over--or underestimation of dietary questionnaire measurements. Besides optimizing the statistical power, it is important that the magnitude of the predicted variation in true intake level is estimated accurately, so as to allow unbiased estimations of relative risks. To meet these various objectives, substudies must be conducted for the 'validation' or 'calibration' of dietary questionnaire assessments, by comparison with additional measurements that have independent sources of error. This paper reviews the methodological considerations underlying the design and implementation of such substudies in the EPIC project, a collaborative multicentre study in nine Western European countries.

Diet↗

PubMed1997

The Malmö Food Study: validity of two dietary assessment methods for measuring nutrient intake.

BACKGROUND: Nutritional epidemiology relies largely on dietary assessment methods for the estimation of the "exposure' variables which may be related to disease risk. METHODS: This paper describes a methodological study conducted in Malmö, Sweden, to compare nutrient intake--estimated by two alternative dietary assessment methods--with a reference method consisting of 18 days of weighed food records. The two candidate methods were an extensive food frequency questionnaire with portion size to be estimated from a booklet of 120 sets of photos (method A) and a method involving the combination of a shorter questionnaire and a two-week food record (method B). RESULTS: In absolute values, both methods overestimated nutrient intake by 20-40%, with method B closer to the reference for most nutrients. Both crude and energy-adjusted correlations between A-reference and B-reference were of the order of 0.50-0.60 for energy, energy-providing nutrients and most vitamins and minerals. Correlations were in the same range for most of the 14 fatty acids considered in the analyses. Protein intake, estimated from the analyses of urinary nitrogen on 6-8 repeated 24-hour urine collections per subject, was almost identical to the reference method values. Correlation between nitrogen-derived values and dietary measurement was 0.75. CONCLUSIONS: Overall, the study indicated that both methods A and B had good ranking validity compared to the reference and that in most cases the combined method (B) performed slightly better than the extensive food frequency method (A).

Aged↗

PubMed1997

Pilot phase studies on the accuracy of dietary intake measurements in the EPIC project: overall evaluation of results. European Prospective Investigation into Cancer and Nutrition.

BACKGROUND: As part of the European Prospective investigation into Cancer and Nutrition (EPIC), preliminary studies were conducted to evaluate the accuracy of individuals' dietary intake measurements from newly developed questionnaires. METHODS: In six countries that adhered from the very beginning to the multicentre, co-ordinated EPIC project, the validity studies were based on two repeat questionnaire measurements at the start and at the end of a 1-year period, in groups of about 100 volunteers of both sexes. In addition, during this year, up to 12 24-hour recalls per person were taken monthly, and up to four blood and urine specimens were collected for measurement of biochemical markers. In three countries that joined EPIC later, the designs of the validity studies and type of 'reference' measurement chosen were somewhat different. The results presented in this overview paper are taken partly from more detailed, country-specific publications, and partly from a central (re-)analysis of the original data, to ensure a uniform approach to the statistical analyses and presentation. RESULTS: Averaged over subgroups by country and gender, Spearman coefficients of correlation between questionnaire measurements and the individuals' average 24-hour recalls ranged from 0.37 for fish to 0.68 for dairy products and 0.79 for alcoholic beverages. For energy-adjusted nutrient intakes (or nutrient densities, in the UK), mean Pearson correlation coefficients, corrected for residual attenuation due to day-to-day variations in the 24-hour recalls in all but two countries, ranged from 0.37 for retinol and 0.48 for vitamin E to 0.60 for carbohydrates and 0.12 for total alcohol intake. Correlations between energy-adjusted nutrient intakes and biochemical markers on average were low, but varied considerably between study centres. CONCLUSIONS: On average, most estimated correlation coefficient were of similar magnitude to those observed by independent research groups. The role of the preliminary validity studies, and various benefits drawn from these studies for further planning of the EPIC project are discussed.

Diet↗

PubMed1997

The EPIC Project: rationale and study design. European Prospective Investigation into Cancer and Nutrition.

BACKGROUND: The most consistent result of epidemiological studies on diet and cancer is that a diet rich in vegetables, fruit and, more generally, in plant foods is associated with a reduced risk of cancer at several anatomical sites. Epidemiological studies have been less consistent regarding the putative increase in risk related to consumption of fat or meat. In addition it has not been possible to identify clearly the biological role of specific nutrients or non-nutrient food components in the prevention or causation of cancer. Limitations in the precision and validity of traditional dietary intake measurements and limited use of biomarkers combined with narrow ranges of variations in dietary habits within single populations, have been the main reasons for the limited success in identifying more specific diet and cancer links. METHODS: EPIC is a multi-centre prospective cohort study designed to investigate the relation between diet, nutritional and metabolic characteristics, various lifestyle factors and the risk of cancer. The study is based in 22 collaborating centres in nine European countries and includes populations characterized by large variations in dietary habits and cancer risk. Data are collected on diet, physical activity, sexual maturation and reproductive history, lifetime consumption of alcohol and tobacco, previous and current illnesses and current medication. Following a common protocol and using identical equipment, blood samples are collected, aliquoted into plasma, serum, white blood cells and erythrocytes, and stored in liquid nitrogen at -196 degrees C for future laboratory analyses on cancer cases and matched healthy controls. Anthropometric measurements are taken according to a standard protocol. It is planned to include around 400,000 middle-aged men and women. RESULTS AND CONCLUSIONS: The collection of questionnaire data, anthropometric measurements and blood samples is under way. Almost 340,000 subjects had been included in the study by mid-1996, and recruitment is expected to be almost complete by 1997. Follow-up for cancer incidence and total mortality has started and it is expected that about 23000 cancer cases will be identified during the first 10 years of follow-up.

Adult↗

PubMed1997

Biochemical markers of dietary intake.

The primary objective of nutritional epidemiology is to identify, in combination with other forms of research, which aspects of diet and nutritional factors are causally related to cancer development. However, traditional epidemiology can evaluate with only a limited degree of specificity to which individual dietary factors an increased occurrence of cancer can be attributed. The two main reasons for this are: (1) dietary intake levels of specific foods or food constituents can be strongly intercorrelated; (2) dietary intake levels of specific food constituents are generally measured with rather large errors. Biochemical markers are increasingly seen as measurements that may help to overcome some of the above-mentioned methodological problems in nutritional epidemiology.

Biomarkers, Tumor↗

PubMed1996

Diet and cancers of the larynx and hypopharynx: the IARC multi-center study in southwestern Europe.

The main causes of cancer of the larynx and hypopharynx are smoking cigarettes and drinking alcohol. However, for these as well as for other cancers of the upper aerodigestive tract, some dietary components, mainly low consumption of fruit and vegetables, have been observed to be associated with increased cancer risk. We report results from a multicenter case-control study carried out in six regions of Europe located in northern Spain, northern Italy, Switzerland, and France. A total of 1,147 males with cancer (cases) and 3,057 population controls were interviewed on usual diet, lifelong drinking and smoking habits, and occupational history. Cancer cases had histologically verified epidermoid carcinomas. The cancers were classified in two anatomic sub-entities: the epilarynx (hypopharynx and upper part of the larynx), which enters into contact with the bolus and the air; and the endolarynx, through which air and tobacco smoke pass, but not the bolus. A previous report from this study found that alcohol drinking presents a greater risk factor for cancer of the epilarynx than for cancer of the endolarynx. The main results regarding diet indicate that high intake of fruit, vegetables, vegetable oil, fish, and low intake of butter and preserved meats were associated with reduced risk of both epilaryngeal and endolaryngeal cancers, after adjustment for alcohol, tobacco, socioeconomic status, and non-alcohol energy intake. Among nutrients, a reduced risk was found for high intake of vitamins C and E and for a high polyunsaturated/saturated fatty acids (P/S) ratio. While these variables are relevant in scoring nutritional behaviour, it remains unresolved whether the biologic properties of these nutrients play a role in the apparent protective effect.

Alcohol Drinking↗