Population attributable risk for breast cancer: diet, nutrition, and physical exercise.

BACKGROUND The percentages of breast cancer cases in a given population attributable to specific risk factors (i.e., the population-attributable risks) can be calculated; determination of such risks associated with potentially modifiable risks factors, such as diet (e.g., levels of consumption of fruits, vegetables, vitamins, etc.), alcohol consumption, exercise, and body weight, are necessary to focus prevention strategies. METHODS With the use of data from a case-control study conducted in Italy from June 1991 through April 1994 on 2569 breast cancer case subjects and 2588 control subjects, we calculated multivariate odds ratios and population-attributable risks for breast cancer in relation to dietary beta-carotene and vitamin E intake, alcohol consumption, physical activity, and, for postmenopausal women, body mass index. RESULTS Among all subjects, the following attributable risks for the indicated risk factors were observed: 10.7% (95% confidence interval [CI] = 4.4%-17.0%) for high alcohol intake (i.e., >20 g/day), 15.0% (95% CI = 7.4%-22.9%) for low beta-carotene intake (i.e., <3366 microg/day), 8.6% (95% CI = -0.4%-17.5%) for low vitamin E intake (i.e., <8.5 mg/day), and 11.6% (95% CI = -0.1%-23.3%) for low levels of physical activity. The risks associated with alcohol and beta-carotene intake were larger among premenopausal women, and the risk associated with physical activity was larger among postmenopausal women. Being overweight accounted for 10.2 % (95% CI = 0.2%-20.2%) of breast cancer cases in postmenopausal women. Beta-carotene plus alcohol accounted for 28.1% (95% CI = 16.8-39.4) of the cases. Beta-carotene and physical activity accounted for 32% (95% CI = 14.3-49.8), and these three factors together accounted for 33% (95% CI = 19.9-46.1) of the breast cancer cases in the overall dataset. CONCLUSION Exposure to a few selected and potentially modifiable risk indicators explained about one third of the cases of breast cancer in this Italian population, indicating the theoretical scope for prevention of the disease.

[1]  S. Cénée,et al.  The role of fat, animal protein and some vitamin consumption in breast cancer: A case control study in Southern France , 2007, International journal of cancer.

[2]  C. la Vecchia,et al.  Trends in overweight and obesity among Italian adults, 1983 through 1994. , 1997, American journal of public health.

[3]  C. la Vecchia,et al.  Attributable risks for breast cancer in Italy: Education, family history and reproductive and hormonal factors , 1997, International journal of cancer.

[4]  C. la Vecchia,et al.  Cancer Mortality in Italy, 1992 , 1996, Tumori.

[5]  C. la Vecchia,et al.  Validity and reproducibility of alcohol consumption in Italy. , 1996, International journal of epidemiology.

[6]  D. Amadori,et al.  Body size indices and breast cancer risk before and after menopause , 1996, International journal of cancer.

[7]  D. Amadori,et al.  Intake of macronutrients and risk of breast cancer , 1996, The Lancet.

[8]  O. Nanni,et al.  Physical activity and breast cancer risk. , 1996, Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology.

[9]  P Gnagnarella,et al.  Validation of a food-frequency questionnaire to assess dietary intakes in cancer studies in Italy. Results for specific nutrients. , 1996, Annals of epidemiology.

[10]  E. Negri,et al.  The Food Composition Database for an Italian Food Frequency Questionnaire , 1996 .

[11]  J Benichou,et al.  Software for attributable risk and confidence interval estimation in case-control studies. , 1996, Computers and biomedical research, an international journal.

[12]  C. la Vecchia,et al.  Intake of selected micronutrients and the risk of breast cancer , 1996, International journal of cancer.

[13]  J Benichou,et al.  Proportion of breast cancer cases in the United States explained by well-established risk factors. , 1995, Journal of the National Cancer Institute.

[14]  W. Willett,et al.  Risk of breast cancer in relation to lifetime alcohol consumption. , 1995, Journal of the National Cancer Institute.

[15]  L. Lipworth Epidemiology of breast cancer. , 1995, European journal of cancer prevention : the official journal of the European Cancer Prevention Organisation.

[16]  B. Henderson,et al.  Physical exercise and reduced risk of breast cancer in young women. , 1994, Journal of the National Cancer Institute.

[17]  K. Katsouyanni,et al.  Ethanol and breast cancer: An association that may be both confounded and causal , 1994, International journal of cancer.

[18]  W. Willett,et al.  Micronutrients and cancer risk. , 1994, The American journal of clinical nutrition.

[19]  R. D'Agostino,et al.  Physical activity and risk of breast cancer in the Framingham Heart Study. , 1994, American journal of epidemiology.

[20]  J. Manson,et al.  A prospective study of the intake of vitamins C, E, and A and the risk of breast cancer. , 1993, The New England journal of medicine.

[21]  J Benichou,et al.  Variance calculations and confidence intervals for estimates of the attributable risk based on logistic models. , 1990, Biometrics.

[22]  B. Modan,et al.  Dietary factors and risk of breast cancer: combined analysis of 12 case-control studies. , 1990, Journal of the National Cancer Institute.

[23]  C. la Vecchia,et al.  Body weight and the prevalence of chronic diseases. , 1988, Journal of epidemiology and community health.

[24]  W. Willett,et al.  Moderate alcohol consumption and the risk of breast cancer. , 1987, The New England journal of medicine.

[25]  A Trichopoulou,et al.  Diet and breast cancer: A case‐control study in Greece , 1986, International journal of cancer.

[26]  D P Byar,et al.  Estimating the population attributable risk for multiple risk factors using case-control data. , 1985, American journal of epidemiology.

[27]  C. la Vecchia,et al.  Menstrual cycle patterns and the risk of breast disease. , 1985, European journal of cancer & clinical oncology.

[28]  R. Bostick,et al.  Vitamin E and breast cancer: a review. , 1997, Nutrition and cancer.

[29]  O. Nanni,et al.  Reproducibility of an Italian food frequency questionnaire for cancer studies. Results for specific nutrients. , 1995, Annals of epidemiology.

[30]  E. Wynder,et al.  A case-control study on breast cancer and body mass , 1995 .

[31]  O. Nanni,et al.  Reproducibility of an Italian food frequency questionnaire for cancer studies: results for specific food items. , 1993, European journal of cancer.

[32]  W. Willett,et al.  Diet, body size, and breast cancer. , 1993, Epidemiologic reviews.

[33]  G. Block Dietary guidelines and the results of food consumption surveys. , 1991, The American journal of clinical nutrition.

[34]  N. Breslow,et al.  The analysis of case-control studies , 1980 .