Adriano Decarli

VALIDATION OF A FOOD-FREQUENCY QUESTIONNAIRE TO ASSESS DIETARY INTAKES IN CANCER STUDIES IN ITALY RESULTS FOR SPECIFIC NUTRIENTS

The validity of a 77-item food-frequency questionnaire (FFQ) developed for a multicenter case-control study on diet and cancer in Italy was assessed. Trained interviewers administered the same FFQ to 452 volunteers from three Italian provinces (Pordenone, Genoa, and Forli) completed in two different seasons, at an interval of 3 to 10 months. For 395 (130 males, 265 females; median age = 52 years; range = 35 to 69 years) volunteers, two 7-day dietary (7-DD) records were available. Average intake obtained by means of the FFQ was overestimated by approximately 18% in comparison with the corresponding values based on the two 7-DD records (reference method). Pearson partial correlation coefficients, adjusted for total energy intake between the nutrient intakes assessed by the FFQ and reference method, ranged from 0.19 for vegetable fat to 0.64 for sugar (median value r = 0.46). The unadjusted deattenuated coefficients, which took into account the interindividual variability of consumption, estimated by means of the two 7-DD records, ranged from 0.29 for vegetable fat to 0.72 for starch (median value r = 0.54). The proportion of subjects correctly classified within the lowest two quintiles ranged between 59% for vegetable fat and vitamin E, and 96% for alcohol, and those correctly classified within the highest two quintiles ranged between 44% for vegetable fat and 94% for alcohol. The average proportion of subjects correctly classified within one quintile was 73%. These data indicate that this FFQ provides valid estimates of intakes for major nutrients, comparable to those reported from other studies in North America and other European countries.

Food groups and risk of colorectal cancer in Italy

The proportion of colorectal cancer attributed to dietary habits is high, but several inconsistencies remain, especially with respect to the influence of some food groups. To further elucidate the role of dietary habits, 1,225 subjects with cancer of the colon, 728 with cancer of the rectum and 4,154 controls, hospitalized with acute non‐neoplastic diseases, were interviewed between 1992 and 1996 in 6 different Italian areas. The validated food‐frequency questionnaire included 79 questions on food items and recipes, categorised into 16 food groups. After allowance for non‐dietary confounding factors and total energy intake, significant trends of increasing risk of colorectal cancer with increasing intake emerged for bread and cereal dishes (odds ratio [OR] in highest vs. lowest quintile = 1.7), potatoes (OR = 1.2), cakes and desserts (OR = 1.1), and refined sugar (OR = 1.4). Intakes of fish (OR = 0.7), raw and cooked vegetables (OR = 0.6 for both) and fruit other than citrus fruit (OR = 0.7) showed a negative association with risk. Consumption of eggs and meat (white, red or processed meats) seemed uninfluential. Most findings were similar for colon and rectum, but some negative associations (i.e., coffee and tea, and fish) appeared stronger for colon cancer. Our findings lead us to reconsider the role of starchy foods and refined sugar in light of recent knowledge on the digestive physiology of carbohydrates and the insulin/colon cancer hypothesis. The beneficial role of most vegetables is confirmed, with more than 20% reduction in risk of colorectal cancer from the addition of one daily serving. Int. J. Cancer 72:56–61, 1997.

Reproducibility of an Italian food frequency questionnaire for cancer studies. Results for specific nutrients

The reproducibility of measures of the intake of total energy and 27 selected nutrients from a quantitative food frequency questionnaire (FFQ) used in a case-control study on cancer of the breast, ovary, and digestive tract was evaluated. The results of two FFQ administrations at an interval of 3 to 10 months (median = 5.4 months) to 452 volunteers (144 males and 308 females; median age = 50 years) from three Italian provinces (Pordenone, Genoa, and Forì) were compared. Pearson correlation coefficients (r) between crude nutrient intake (unadjusted for energy) ranged from 0.50 for vegetable fat to 0.80 for alcohol, with most values falling between 0.60 and 0.70 (median r = 0.67). Adjustment of nutrient intakes for total energy slightly decreased most coefficients (median r = 0.60). The agreement between the two measurements did not differ substantially by sex, age, education, and interval between interviews. The contribution of specific FFQ components (i.e., frequency-only questions, open questions, portion size, and fat intake pattern) was also assessed separately with respect to the performance and reproducibility of nutrient measures, yielding, in general, very similar results. The seven questions concerning individual fat intake pattern, which were used to modulate the composition of various recipes, led, however, to a significant increase in mean daily intake of vegetable fat, oleic acid, and vitamin E, but a reduction of estimated daily intake of linoleic acid and polyunsaturated fatty acids.(ABSTRACT TRUNCATED AT 250 WORDS)

Olive oil, other dietary fats, and the risk of breast cancer (Italy).

Data from a multicenter case-control study on breast cancer conducted in Italy have been used to analyze the relationship of olive oil and other dietary fats to breast cancer risk. Cases were 2,564 women hospitalized with histologically confirmed, incident breast cancer. Controls were 2,588 women admitted to the same network of hospitals for acute, non-neoplastic, non-hormone related, on-digestive tract disorders. Cases and controls were interviewed between 1991 and 1994 using a validated food-frequency questionnaire. The data were modelled through multiple logistic regression controlling for demographic and reproductive breast-cancer risk factors, energy intake and, mutually, for types of dietary fat. For olive oil, compared with the lowest quintile, the odds ratios (OR) were 1.05, 0.99, 0.93, and 0.87 for increasing quintiles of intake; in a model postulating linear logit increase, the OR per unit (30g) was 0.89 (95 percent confidence interval [CI]=0.81–0.99, P=0.03). Among other oils or fats considered, the OR for the highest level of intake was 0.72 (CI=0.6–0.9) for a group of specific seed oils (including safflower, maize, peanut, and soya) compared with nonusers. The ORs for the highest cf lowest level of intake were 0.80 for mixed or unspecified seed oils, 0.95 for butter, and 0.96 for margarine. The study, based on a large dataset from various Italian regions, shows an inverse relationship of breast cancer risk with intake of olive oil and other vegetable oils, but not with butter or margarine.

Intake of selected micronutrients and risk of colorectal cancer

The relationship between various micronutrients and colorectal cancer risk was investigated using data from a case‐control study conducted between January 1992 and June 1996 in Italy. Cases were 1,953 incident, histologically confirmed colorectal cancers (1,225 of the colon and 728 of the rectum), admitted to the major teaching and general hospitals in the study areas, and 4,154 controls with no history of cancer, admitted to hospitals in the same catchment areas for acute, non‐neoplastic diseases unrelated to the digestive tract and requiring no long‐term modifications of the diet. Dietary habits were investigated using a validated food‐frequency questionnaire. Odds ratio (ORs) were computed after allowance for age, sex and other potential confounding factors, including physical activity, total energy and fibre intake. For most micronutrients, ORs were below unity with increasing quintile of intake. The most consistent protective effects were for carotene, riboflavin and vitamin C (Multivariate ORs from the continuous model, with unit set as the difference between the upper cut‐point of the 4th quintile and that of the 1st one, were 0.65, 0.73 and 0.80, respectively). Inverse relationships were observed also for calcium and vitamin D (ORs of 0.85 and 0.93, respectively). When the combined effect of calcium and vitamin D and selected anti‐oxidants was considered, the OR reached 0.46 in subjects reporting high calcium/vitamin D and high anti‐oxidant intake compared to those reporting low intake of both groups of micronutrients. Most results were apparently stronger for colon cancer and among females. Our results provide further support for a protective effect of several micronutrients on colorectal cancer risk and some indications for a specific and stronger effect of selected anti‐oxidants. Int. J. Cancer 73:525–530, 1997.

Intake of macronutrients and risk of breast cancer

BACKGROUND The association between risk of breast cancer and dietary fat and intakes of other energy sources remains controversial. The Italian population offers special opportunities to assess the influence of high intakes of unsaturated fat and starch and, because the population has low awareness of diet and cancer issues, there is less scope for recall bias. We have assessed the relations of various macronutrient intakes with risk of breast cancer. METHODS In this case-control study, 2569 women with incident breast cancer (median age 55 years) and 2588 control women (median age 56 years) in hospital with acute, non-neoplastic diseases, were interviewed in six different areas of Italy between 1991 and 1994. A validated food-frequency questionnaire was used. It included questions on 78 foods and recipes grouped into six sections, as well as specific questions on individual fat intake pattern. FINDINGS The risk of breast cancer decreased with increasing total fat intake (trend p 0.01) whereas the risk increased with increasing intake of available carbohydrates (trend p = 0.002). The odds ratios for women in the highest compared with the lowest quintile of energy-adjusted intake were 0.81 for total fat and 1.30 for available carbohydrates. Starch was the chief contributor to the positive association with available carbohydrates. High intakes of polyunsaturated and unsaturated fatty acids (i.e., polyunsaturated fatty acids plus oleic acid) were associated with a decreased risk of breast cancer (odds ratios for highest vs lowest quintile 0.70 and 0.74, respectively). Conversely, the intakes of saturated fatty acids, protein, and fibre were not significantly associated with breast-cancer risk. INTERPRETATION This case-controls study shows that unsaturated fatty acids protect against breast cancer, possibly because intake of these nutrients is closely correlated with a high intake of raw vegetables. The findings also suggest a possible risk in southern European populations, of reliance on a diet largely based on starch.

Intake of selected micronutrients and the risk of breast cancer

To investigate the relation between selected micronutrients and breast cancer risk, we conducted a case‐control study of breast cancer between June 1991 and April 1994 in 6 Italian areas. The study included 2569 women admitted to the major teaching and general hospitals of the study areas with histologically confirmed incident breast cancer and 2588 control women with no history of cancer, who were admitted to hospitals in the same catchment areas for acute, non‐neoplastic, nongynecological conditions unrelated to hormonal or digestive tract diseases or to long‐term modifications of the diet. Dietary habits, including alcoholic beverage consumption, were investigated using a validated food frequency questionnaire, including 78 foods or food groups, several types of alcoholic beverages, some “fat intake pattern” questions and some open sections for foods consumed frequently by the subject and not reported in the questionnaire. To control for potential confounding factors, several multiple logistic regression models were used. When major correlates, energy intake and the mutual confounding effect of the various micronutrients were taken into account, beta‐carotene, vitamin E and calcium showed a significant inverse association with breast cancer risk. The estimated odds ratios of the 5th quintile compared to the lowest one were 0.84 for beta‐carotene, 0.75 for vitamin E and 0.81 for calcium. No significant association emerged for retinol, vitamin C, thiamin, riboflavin, iron and potassium. Our results suggest that a diet rich in several micronutrients, particularly beta‐carotene, vitamin E and calcium, may be protective against breast cancer.

Nutrition and diet in the etiology of endometrial cancer

The risk of endometrial cancer in relation to nutrition and frequency of consumption of a few selected dietary items was evaluated in a case‐control study of 206 patients with endometrial cancer and 206 control subjects with acute conditions unrelated to any of the established or potential risk factors for endometrial cancer. Obesity was strongly and positively associated with the risk of endometrial cancer, and several conditions related to body weight, such as early menarche, diabetes mellitus, or hypertension were more common in cases. The risk of endometrial cancer was elevated in subjects reporting (on a subjective basis) greater fat (butter, margarine, and oil) intake (relative risk estimate for the higher compared to the lower scores equals 5.65, with 95% confidence interval of 2.76–11.55). Cases reported less frequent intake of green vegetables, fruit, and whole‐grain foods: thus, the risk of endometrial cancer appeared inversely related to indices of beta‐carotene and fiber intake. Furthermore, cases consumed milk, liver and fish less frequently than controls. No significant difference was noted between cases and controls in the frequency of intake of carrots, meat, eggs, ham, and cheese. Alcohol consumption was somewhat larger among the cases, but this trend in risk was not significant. Dietary information collected in this study probably is too limited and inconsistent to permit analysis of biologic correlates of these findings or discussion of their potential implications in terms of prevention on a public health scale. Nonetheless, the mere existence of differences in reported diet between endometrial cancer cases and controls is of interest, and may warrant further, more detailed investigation.

Dietary patterns, nutrient intake and gastric cancer in a high-risk area of Italy

AbstractObjectives: To better understand the role of overall dietary patterns and major energy-providing components in gastric cancer etiology. Methods: In a population-based case–control study conducted in a high-risk area in central Italy, 382 gastric cancer cases and 561 controls were available for analysis. Multivariate models based on energy-adjusted residuals and completely partitioned logistic models were used; dietary patterns were evaluated by factor analysis and multiple correspondence analysis. Results: Gastric cancer risk was inversely related to high energy-adjusted intakes of vegetable fat, sugar, beta-carotene, vitamin C, alpha-tocopherol, and nitrates. In contrast, significant positive associations emerged with high intake of protein, nitrite, and sodium. According to energy decomposition models, gastric cancer risk increased with increasing intake of protein and decreased with increasing intake of sugar and total fat. The pattern analysis identified four dietary profiles, overall explaining 75% of total dietary variability. Two patterns, named “traditional” and “vitamin-rich”, were strongly associated with gastric cancer risk and overall accounted for 44% of estimated gastric cancer attributable risk. The other two patterns, “refined” and “fat-rich”, were not consistently associated with gastric cancer. Conclusion: Innovative methodological approaches may contribute to better evaluation of the complex relationship between diet and cancer risk and to planning dietary interventions.

Cancer mortality in Europe: effects of age, cohort of birth and period of death

Death certification data for 19 cancers or groups of cancers, plus total cancer mortality, in 16 major European countries were analysed using a log-linear Poisson model with arbitrary constraints on the parameters to disentangle the effects of age, birth cohort and period of death. Three major patterns emerged including: first, the prominent role of cohort of birth in defining trends in mortality from most cancer sites (except testis or Hodgkins disease, where newer treatments had a major period of death effect); and second, the major role of lung and other tobacco-related neoplasm epidemics in determining the diverging pattern of cancer mortality, for each sex and in various European countries and geographic areas. In most countries, the peak male cohort values were reached for generations born between 1900 and 1930. This was observed in women only for Denmark and the U.K., i.e. the two countries where lung and other tobacco-related neoplasm epidemics had already reached appreciable levels. This confirms the importance of cigarette smoking in subsequent generations as a major cause of cancer deaths in Europe. Further, there is a persistent rise in several cancer rates, again chiefly on a cohort basis, in Eastern Europe, which calls for urgent intervention to control the cancer burden in these countries.