D. Trichopoulos

Animal foods, protein, calcium and prostate cancer risk: the European Prospective Investigation into Cancer and Nutrition

We examined consumption of animal foods, protein and calcium in relation to risk of prostate cancer among 142u2009251 men in the European Prospective Investigation into Cancer and Nutrition. Associations were examined using Cox regression, stratified by recruitment centre and adjusted for height, weight, education, marital status and energy intake. After an average of 8.7 years of follow-up, there were 2727 incident cases of prostate cancer, of which 1131 were known to be localised and 541 advanced-stage disease. A high intake of dairy protein was associated with an increased risk, with a hazard ratio for the top versus the bottom fifth of intake of 1.22 (95% confidence interval (CI): 1.07–1.41, Ptrend=0.02). After calibration to allow for measurement error, we estimated that a 35-gu2009day−1 increase in consumption of dairy protein was associated with an increase in the risk of prostate cancer of 32% (95% CI: 1–72%, Ptrend=0.04). Calcium from dairy products was also positively associated with risk, but not calcium from other foods. The results support the hypothesis that a high intake of protein or calcium from dairy products may increase the risk for prostate cancer.

Conformity to traditional Mediterranean diet and cancer incidence: the Greek EPIC cohort.

Adherence to traditional Mediterranean diet (MD) has been reported to be inversely associated with total, as well as cardiovascular, mortality. We have examined the relation between degree of such adherence and incidence of cancer overall in a general population sample of 25u2009623 participants (10u2009582 men, 15u2009041 women) of the Greek segment of the European Prospective Investigation into Cancer and nutrition (EPIC). All subjects completed a validated, interviewer-administered, semi-quantitative food-frequency questionnaire at enrolment. Degree of adherence to the traditional MD was assessed through a 10-point scale (0 minimal; 9 maximal) that incorporated key dietary characteristics. During a median follow-up of 7.9 years and 188u2009042 total person-years, 851 medically confirmed incident cancer cases (421 men, 430 women) were recorded. Using proportional hazards regression with adjustment for potential confounders, we found that a higher degree of MD adherence was associated with lower overall cancer incidence. A two-point increase in the score corresponded to a 12% reduction in cancer incidence (adjusted hazard ratio, 0.88 (95% confidence interval 0.80, 0.95)). The association was exposure-dependent and stronger among women. This inverse association with MD adherence was considerably stronger than that predicted on the basis of the associations of the individual components of this diet and points to the value of analysing dietary patterns in cancer studies.

Reliability of information on cigarette smoking and beverage consumption provided by hospital controls

We compared data from interviews of patients admitted to hospital and interviews repeated at home for 400 hospital controls. Of these, 294 (73.5%) could be re-interviewed (responders). Never smoking was reported by 44% of subjects in the in-hospital interviews and by 40% in the repeat at-home interviews. Among those interviewed in hospital, 38% claimed to be nondrinkers, as did 38% of responders, but only 28% characterized themselves as nondrinkers in the repeat interview. For consumption of regular coffee, 15% reported none in the selected sample, 14% among responders, but only 6% in the repeat at-home interview. Agreement was good for decaffeinated coffee and tea consumption.

Flavonoid intake and breast cancer risk: a case--control study in Greece.

Flavonoids have been investigated for possible inverse associations with various chronic degenerative diseases, but there are no epidemiologic data concerning a possible association between several of the main flavonoid categories and breast cancer risk. We have applied recently published data on the flavonoid content of several foods and beverages on dietary information collected in the context of a large case–control study of 820 women with breast cancer and 1548 control women, conducted in Greece. We found a strong, statistically significant inverse association of flavone intake with breast cancer. The odds ratio for an increment equal to one standard deviation of daily flavone intake (i.e. 0.5u2009mgu2009day−1) was 0.87, with 95% confidence interval 0.77–0.97. The association persisted after controlling for fruit and vegetable consumption, or for other flavonoid intake. This inverse association is compatible with and may explain the reported inverse association of breast cancer with consumption of vegetables, particularly leafy vegetables. After controlling for dietary confounding, there was no association of breast cancer risk with flavanones, flavan-3-ols, flavonols, anthocyanidins or isoflavones.

Sex hormones and risk of breast cancer in premenopausal women: a collaborative reanalysis of individual participant data from seven prospective studies

BACKGROUNDnAssociations between circulating concentrations of oestrogens, progesterone, and androgens with breast cancer and related risk factors in premenopausal women are not well understood. We aimed to characterise these associations with a pooled analysis of data from seven studies.nnnMETHODSnIndividual participant data for prediagnostic sex hormone and sex hormone-binding globulin (SHBG) concentrations were contributed from seven prospective studies. We restricted analyses to women who were premenopausal and younger than 50 years at blood collection, and to women with breast cancer diagnosed before age 50 years. We estimated odds ratios (ORs) with 95% CIs for breast cancer associated with hormone concentrations by conditional logistic regression in cases and controls matched for age, date of blood collection, and day of cycle, with stratification by study and further adjustment for cycle phase. We examined associations of hormones with risk factors for breast cancer in control women by comparing geometric mean hormone concentrations in categories of these risk factors, adjusted for study, age, phase of menstrual cycle, and body-mass index (BMI). All statistical tests were two-sided.nnnFINDINGSnWe included data for up to 767 women with breast cancer and 1699 controls in the risk analyses. Breast cancer risk was associated with a doubling in concentrations of oestradiol (OR 1·19, 95% CI 1·06-1·35), calculated free oestradiol (1·17, 1·03-1·33), oestrone (1·27, 1·05-1·54), androstenedione (1·30, 1·10-1·55), dehydroepiandrosterone sulphate (1·17, 1·04-1·32), testosterone (1·18, 1·03-1·35), and calculated free testosterone (1·08, 0·97-1·21). Breast cancer risk was not associated with luteal phase progesterone (doubling in concentration OR 1·00, 95% CI 0·92-1·09), and adjustment for other factors had little effect on any of these ORs. Cross-sectional analyses in control women showed several associations of sex hormones with breast cancer risk factors.nnnINTERPRETATIONnCirculating oestrogens and androgens are positively associated with the risk for breast cancer in premenopausal women.

Risk of breast cancer among greek women in relation to nutrient intake

A case‐control study of the role of diet in the cause of breast cancer was conducted in Athens, Greece. The case series consisted of 120 consecutive patients with histologically confirmed breast cancer admitted to either of two teaching hospitals over a 12‐month period. The controls were 120 patients admitted to a teaching hospital for trauma and orthopedic conditions during the same period. Dietary histories concerning the frequency of consumption of 120 foods and drinks were obtained by interview. Nutrient intakes for individuals were estimated by multiplying the nutrient content of a selected typical portion size for each specified food item by the frequency that the food was used per month and summing these estimates for all food items. Cases reported significantly less frequent consumption of vitamin A after controlling for total caloric intake, potential external confounding variables and other nutrients associated with breast cancer risk. The odds ratio estimated for consumption of vitamin A equal to the value of the 90th centile versus consumption equal to the value of the 10th centile was 0.46 with 90% confidence limits 0.26–0.82. There was no evidence that high intake of dietary fat increases the risk of breast cancer.

Low-carbohydrate–high-protein diet and long-term survival in a general population cohort

Objective:We have evaluated the effects on mortality of habitual low carbohydrate–high-protein diets that are thought to contribute to weight control.Design:Cohort investigation.Setting:Adult Greek population.Subjects methods:Follow-up was performed from 1993 to 2003 in the context of the Greek component of the European Prospective Investigation into Cancer and nutrition. Participants were 22u2009944 healthy adults, whose diet was assessed through a validated questionnaire. Participants were distributed by increasing deciles according to protein intake or carbohydrate intake, as well as by an additive score generated by increasing decile intake of protein and decreasing decile intake of carbohydrates. Proportional hazards regression was used to assess the relation between high protein, high carbohydrate and the low carbohydrate–high protein score on the one hand and mortality on the other.Results:During 113u2009230 persons years of follow-up, there were 455 deaths. In models with energy adjustment, higher intake of carbohydrates was associated with significant reduction of total mortality, whereas higher intake of protein was associated with nonsignificant increase of total mortality (per decile, mortality ratios 0.94 with 95% CI 0.89 –0.99, and 1.02 with 95% CI 0.98 –1.07 respectively). Even more predictive of higher mortality were high values of the additive low carbohydrate–high protein score (per 5 units, mortality ratio 1.22 with 95% CI 1.09 –to 1.36). Positive associations of this score were noted with respect to both cardiovascular and cancer mortality.Conclusion:Prolonged consumption of diets low in carbohydrates and high in protein is associated with an increase in total mortality.

Tracing the Mediterranean diet through principal components and cluster analyses in the Greek population

Objective: To identify dietary patterns, and their socio-demographic and lifestyle correlates in a large sample of Greek adults, and assess their adherence to the traditional Mediterranean diet.Design: Principal component (PC) analysis was used to identify dietary patterns among 28 034 participants of the Greek branch of the European Prospective Investigation into Cancer and Nutrition. Dietary information was collected through a validated, semiquantitative, food-frequency questionnaire. The extracted PCs were subsequently regressed on sociodemographic and lifestyle variables. Analyses were also performed to classify individuals with similar dietary behavior into clusters.Results:Four PCs were identified: PC1 resembled the Mediterranean diet, PC2 approximated a vegetarian diet with emphasis on seed oils, PC3 reflected a preference for sweets, and PC4 reflected a Western diet. PC1 and PC2 were positively associated with age, education, physical activity, and nonsmoking status. Females, in comparison to males, scored higher on PC1 but lower on PC2. Males, younger, more educated individuals, nonsmokers and residents of Greater Athens (Attica) scored higher on PC3. PC4 was associated with younger age, less education, and current smoking. In cluster analyses, cluster A contrasted clusters B and C in having much higher mean PC1- and PC2-scores and substantially lower PC3- and PC4-scores. PC1 and PC4 were, respectively, positively and inversely correlated with an a priori Mediterranean-diet score; PC2 and PC3 were unrelated to it.Conclusion: The Mediterranean-like PC1-score as well as the vegetarian-like PC2 were higher among older, more educated people, and were associated with a healthier lifestyle than PC4, which reflected a Western-type diet. PC1 was strongly positively associated with an a priori Mediterranean-diet score.Sponsorship: The European Prospective Investigation into Cancer and Nutrition (EPIC) is coordinated by the International Agency for Research on Cancer and supported by the Europe Against Cancer Programme of the European Commission. The Greek segment of the EPIC study is also supported by the Greek Ministry of Health and the Greek Ministry of Education.

Serum Insulin-like Growth Factor (IGF)-I and IGF-Binding Protein-3 Concentrations and Prostate Cancer Risk: Results from the European Prospective Investigation into Cancer and Nutrition

Background: Some studies suggest that elevated serum insulin-like growth factor (IGF)-I concentrations are associated with an increased risk of prostate cancer and, in particular, with an increased risk of advanced-stage prostate cancer. Methods: We analyzed the association between prediagnostic serum concentrations of IGF-I and IGF-binding protein-3 (IGFBP-3) and prostate cancer risk in a case-control study nested in the European Prospective Investigation into Cancer and Nutrition. This study includes 630 incident prostate cancer cases and 630 matched control subjects. Odds ratios and their 95% confidence intervals (95% CI) were calculated for prostate cancer risk associated with increasing IGF-I and IGFBP-3 concentrations using conditional logistic regression. Results: The risk of total prostate cancer in the highest versus the lowest third of serum peptide concentration was 1.35 (95% CI, 0.99-1.82; Ptrend = 0.08) for IGF-I, 1.39 (95% CI, 1.02-1.89; Ptrend = 0.12) for the IGF-I residuals after adjusting for IGFBP-3, 1.22 (95% CI, 0.92-1.64; Ptrend = 0.38) for IGFBP-3, and 1.01 (95% CI, 0.74-1.37; Ptrend = 0.75) for the IGFBP-3 residuals after adjusting for IGF-I. There was no significant difference in the association of peptide hormones and prostate cancer by stage of disease, although the association of serum IGF-I concentration with risk was slightly stronger for advanced-stage disease; the odds ratio for the highest versus the lowest third was 1.65 (95% CI, 0.88-3.08; Ptrend = 0.21) for IGF-I and 1.76 (95% CI, 0.92-3.40; Ptrend = 0.11) for IGF-I adjusted for IGFBP-3. Conclusions: In this large nested case-control study, serum IGF-I concentration is not strongly associated with prostate cancer risk, although the results are compatible with a small increase in risk, particularly for advanced-stage disease; no association for IGFBP-3 was observed. (Cancer Epidemiol Biomarkers Prev 2007;16(6):1121–7)

Does coffee protect against hepatocellular carcinoma

We analysed the relation between coffee consumption and hepatocellular carcinoma in two case-control studies conducted between 1984 and 1998 in Italy and Greece, including 834 cases and 1912 controls. Compared to non coffee drinkers, the multivariate odds ratio was 0.7 for drinkers of three or more cups per day.