TY - JOUR
T1 - The contribution of risk factors to the higher incidence of invasive and in situ breast cancers in women with higher levels of education in the European prospective investigation into cancer and nutrition
AU - Menvielle, Gwenn
AU - Kunst, Anton E.
AU - Van Gils, Carla H.
AU - Peeters, Petra H.
AU - Boshuizen, Hendriek
AU - Overvad, Kim
AU - Olsen, Anja
AU - Tjonneland, Anne
AU - Hermann, Silke
AU - Kaaks, Rudolf
AU - Bergmann, Manuela M.
AU - Illner, Anne Kathrin
AU - Lagiou, Pagona
AU - Trichopoulos, Dimitrios
AU - Trichopoulou, Antonia
AU - Palli, Domenico
AU - Berrino, Franco
AU - Mattiello, Amelia
AU - Tumino, Rosario
AU - Sacerdote, Carlotta
AU - May, Anne
AU - Monninkhof, Evelyn
AU - Braaten, Tonje
AU - Lund, Eiliv
AU - Quirós, José Ramón
AU - Duell, Eric J.
AU - Sánchez, Maria José
AU - Navarro, Carmen
AU - Ardanaz, Eva
AU - Borgquist, Signe
AU - Manjer, Jonas
AU - Khaw, Kay Tee
AU - Allen, Naomi E.
AU - Reeves, Gillian K.
AU - Chajes, Véronique
AU - Rinaldi, Sabina
AU - Slimani, Nadia
AU - Gallo, Valentina
AU - Vineis, Paolo
AU - Riboli, Elio
AU - Bueno-De-Mesquita, H. Bas
PY - 2011/1/1
Y1 - 2011/1/1
N2 - The authors investigated the role of known risk factors in educational differences in breast cancer incidence. Analyses were based on the European Prospective Investigation Into Cancer and Nutrition and included 242,095 women, 433 cases of in situ breast cancer, and 4,469 cases of invasive breast cancer. Reproductive history (age at first full-term pregnancy and parity), exposure to endogenous and exogenous hormones, height, and health behaviors were accounted for in the analyses. Relative indices of inequality (RII) for education were estimated using Cox regression models. A higher risk of invasive breast cancer was found among women with higher levels of education (RII = 1.22, 95% confidence interval (CI): 1.09, 1.37). This association was not observed among nulliparous women (RII = 1.13, 95% CI: 0.84, 1.52). Inequalities in breast cancer incidence decreased substantially after adjusting for reproductive history (RII = 1.11, 95% CI: 0.98, 1.25), with most of the association being explained by age at first full-term pregnancy. Each other risk factor explained a small additional part of the inequalities in breast cancer incidence. Height accounted for most of the remaining differences in incidence. After adjusting for all known risk factors, the authors found no association between education level and risk of invasive breast cancer. Inequalities in incidence were more pronounced for in situ breast cancer, and those inequalities remained after adjustment for all known risk factors (RII = 1.61, 95% CI: 1.07, 2.41), especially among nulliparous women.
AB - The authors investigated the role of known risk factors in educational differences in breast cancer incidence. Analyses were based on the European Prospective Investigation Into Cancer and Nutrition and included 242,095 women, 433 cases of in situ breast cancer, and 4,469 cases of invasive breast cancer. Reproductive history (age at first full-term pregnancy and parity), exposure to endogenous and exogenous hormones, height, and health behaviors were accounted for in the analyses. Relative indices of inequality (RII) for education were estimated using Cox regression models. A higher risk of invasive breast cancer was found among women with higher levels of education (RII = 1.22, 95% confidence interval (CI): 1.09, 1.37). This association was not observed among nulliparous women (RII = 1.13, 95% CI: 0.84, 1.52). Inequalities in breast cancer incidence decreased substantially after adjusting for reproductive history (RII = 1.11, 95% CI: 0.98, 1.25), with most of the association being explained by age at first full-term pregnancy. Each other risk factor explained a small additional part of the inequalities in breast cancer incidence. Height accounted for most of the remaining differences in incidence. After adjusting for all known risk factors, the authors found no association between education level and risk of invasive breast cancer. Inequalities in incidence were more pronounced for in situ breast cancer, and those inequalities remained after adjustment for all known risk factors (RII = 1.61, 95% CI: 1.07, 2.41), especially among nulliparous women.
KW - breast neoplasms
KW - education
KW - incidence
KW - reproductive history
KW - risk factors
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UR - http://www.scopus.com/inward/citedby.url?scp=78650501938&partnerID=8YFLogxK
U2 - 10.1093/aje/kwq319
DO - 10.1093/aje/kwq319
M3 - Article
C2 - 21084553
AN - SCOPUS:78650501938
VL - 173
SP - 26
EP - 37
JO - American Journal of Epidemiology
JF - American Journal of Epidemiology
SN - 0002-9262
IS - 1
ER -