BACKGROUND: Greater weight and body mass index (BMI) are negatively correlated with mammographic density, a strong risk factor for breast cancer, and are associated with an increased risk of breast cancer in postmenopausal women, but with a reduced risk in premenopausal women. We have examined the associations of body size and mammographic density on breast cancer risk. METHOD: We examined the associations of body size and the percentage of mammographic density at baseline with subsequent risk of breast cancer among 1,114 matched case-control pairs identified from three screening programs. The effect of each factor on risk of breast cancer was examined before and after adjustment for the other, using logistic regression. RESULTS: In all subjects, before adjustment for mammographic density, breast cancer risk in the highest quintile of BMI, compared with the lowest, was 1.04 [95% confidence interval (CI), 0.8-1.4]. BMI was associated positively with breast cancer risk in postmenopausal women, and negatively in premenopausal women. After adjustment for density, the risk associated with BMI in all subjects increased to 1.60 (95% CI, 1.2-2.2), and was positive in both menopausal groups. Adjustment for BMI increased breast cancer risk in women with 75% or greater density, compared with 0%, increased from 4.25 (95% CI, 1.6-11.1) to 5.86 (95% CI, 2.2-15.6). CONCLUSION: BMI and mammographic density are independent risk factors for breast cancer, and likely to operate through different pathways. The strong negative correlated between them will lead to underestimation of the effects on risk of either pathway if confounding is not controlled.
BACKGROUND: Greater weight and body mass index (BMI) are negatively correlated with mammographic density, a strong risk factor for breast cancer, and are associated with an increased risk of breast cancer in postmenopausal women, but with a reduced risk in premenopausal women. We have examined the associations of body size and mammographic density on breast cancer risk. METHOD: We examined the associations of body size and the percentage of mammographic density at baseline with subsequent risk of breast cancer among 1,114 matched case-control pairs identified from three screening programs. The effect of each factor on risk of breast cancer was examined before and after adjustment for the other, using logistic regression. RESULTS: In all subjects, before adjustment for mammographic density, breast cancer risk in the highest quintile of BMI, compared with the lowest, was 1.04 [95% confidence interval (CI), 0.8-1.4]. BMI was associated positively with breast cancer risk in postmenopausal women, and negatively in premenopausal women. After adjustment for density, the risk associated with BMI in all subjects increased to 1.60 (95% CI, 1.2-2.2), and was positive in both menopausal groups. Adjustment for BMI increased breast cancer risk in women with 75% or greater density, compared with 0%, increased from 4.25 (95% CI, 1.6-11.1) to 5.86 (95% CI, 2.2-15.6). CONCLUSION: BMI and mammographic density are independent risk factors for breast cancer, and likely to operate through different pathways. The strong negative correlated between them will lead to underestimation of the effects on risk of either pathway if confounding is not controlled.
Authors: Valerie A McCormack; Anya Burton; Isabel dos-Santos-Silva; John H Hipwell; Caroline Dickens; Dorria Salem; Rasha Kamal; Mikael Hartman; Charmaine Pei Ling Lee; Kee-Seng Chia; Vahit Ozmen; Mustafa Erkin Aribal; Anath Arzee Flugelman; Martín Lajous; Ruy Lopez-Riduara; Megan Rice; Isabelle Romieu; Giske Ursin; Samera Qureshi; Huiyan Ma; Eunjung Lee; Carla H van Gils; Johanna O P Wanders; Sudhir Vinayak; Rose Ndumia; Steve Allen; Sarah Vinnicombe; Sue Moss; Jong Won Lee; Jisun Kim; Ana Pereira; Maria Luisa Garmendia; Reza Sirous; Mehri Sirous; Beata Peplonska; Agnieszka Bukowska; Rulla M Tamimi; Kimberly Bertrand; Chisato Nagata; Ava Kwong; Celine Vachon; Christopher Scott; Beatriz Perez-Gomez; Marina Pollan; Gertraud Maskarinec; Graham Giles; John Hopper; Jennifer Stone; Nadia Rajaram; Soo-Hwang Teo; Shivaani Mariapun; Martin J Yaffe; Joachim Schüz; Anna M Chiarelli; Linda Linton; Norman F Boyd Journal: Cancer Epidemiol Date: 2015-12-24 Impact factor: 2.984
Authors: Vicki Hart; Katherine W Reeves; Susan R Sturgeon; Nicholas G Reich; Lynnette Leidy Sievert; Karla Kerlikowske; Lin Ma; John Shepherd; Jeffrey A Tice; Amir Pasha Mahmoudzadeh; Serghei Malkov; Brian L Sprague Journal: Cancer Epidemiol Biomarkers Prev Date: 2015-08-27 Impact factor: 4.254
Authors: Yiwey Shieh; Donglei Hu; Lin Ma; Scott Huntsman; Charlotte C Gard; Jessica W T Leung; Jeffrey A Tice; Celine M Vachon; Steven R Cummings; Karla Kerlikowske; Elad Ziv Journal: Breast Cancer Res Treat Date: 2016-08-26 Impact factor: 4.872
Authors: Reena S Cecchini; Joseph P Costantino; Jane A Cauley; Walter M Cronin; D Lawrence Wickerham; Hanna Bandos; Joel L Weissfeld; Norman Wolmark Journal: Cancer Prev Res (Phila) Date: 2012-10-11
Authors: Deborah J Thompson; Martin O Leach; Gek Kwan-Lim; Simon A Gayther; Susan J Ramus; Iqbal Warsi; Fiona Lennard; Michael Khazen; Emilie Bryant; Sadie Reed; Caroline R M Boggis; D Gareth Evans; Rosalind A Eeles; Douglas F Easton; Ruth M L Warren Journal: Breast Cancer Res Date: 2009-11-11 Impact factor: 6.466
Authors: Lesley M Butler; Ellen B Gold; Shannon M Conroy; Carolyn J Crandall; Gail A Greendale; Nina Oestreicher; Charles P Quesenberry; Laurel A Habel Journal: Cancer Causes Control Date: 2010-02 Impact factor: 2.506