| Title: |
Association of body mass index and age with subsequent breast cancer risk in premenopausal women |
| Authors: |
Group, Premenopausal Breast Cancer Collaborative; Schoemaker, MJ; Nichols, HB; Wright, LB; Brook, MN; Jones, ME; O'Brien, KM; Adami, H-O; Baglietto, L; Bernstein, L; Bertrand, KA; Boutron-Ruault, M-C; Braaten, T; Chen, Y; Connor, AE; Dorronsoro, M; Dossus, L; Eliassen, AH; Giles, GG; Hankinson, SE; Kaaks, R; Key, TJ; Kirsh, VA; Kitahara, CM; Koh, W-P; Larsson, SC; Linet, MS; Ma, H; Masala, G; Merritt, MA; Milne, RL; Overvad, K; Ozasa, K; Palmer, JR; Peeters, PH; Riboli, E; Rohan, TE; Sadakane, A; Sund, M; Tamimi, RM; Trichopoulou, A; Ursin, G; Vatten, L; Visvanathan, K; Weiderpass, E; Willett, WC; Wolk, A; Yuan, J-M; Zeleniuch-Jacquotte, A; Sandler, DP; Swerdlow, AJ |
| Publisher Information: |
American Medical Association |
| Publication Year: |
2019 |
| Collection: |
Oxford University Research Archive (ORA) |
| Description: |
Importance: The association between increasing body mass index (BMI; calculated as weight in kilograms divided by height in meters squared) and risk of breast cancer is unique in cancer epidemiology in that a crossover effect exists, with risk reduction before and risk increase after menopause. The inverse association with premenopausal breast cancer risk is poorly characterized but might be important in the understanding of breast cancer causation.Objective: To investigate the association of BMI with premenopausal breast cancer risk, in particular by age at BMI, attained age, risk factors for breast cancer, and tumor characteristics.Design, Setting, and Participants: This multicenter analysis used pooled individual-level data from 758 592 premenopausal women from 19 prospective cohorts to estimate hazard ratios (HRs) of premenopausal breast cancer in association with BMI from ages 18 through 54 years using Cox proportional hazards regression analysis. Median follow-up was 9.3 years (interquartile range, 4.9-13.5 years) per participant, with 13 082 incident cases of breast cancer. Participants were recruited from January 1, 1963, through December 31, 2013, and data were analyzed from September 1, 2013, through December 31, 2017.Exposures: Body mass index at ages 18 to 24, 25 to 34, 35 to 44, and 45 to 54 years.Main Outcomes and Measures: Invasive or in situ premenopausal breast cancer.Results: Among the 758 592 premenopausal women (median age, 40.6 years; interquartile range, 35.2-45.5 years) included in the analysis, inverse linear associations of BMI with breast cancer risk were found that were stronger for BMI at ages 18 to 24 years (HR per 5 kg/m2 [5.0-U] difference, 0.77; 95% CI, 0.73-0.80) than for BMI at ages 45 to 54 years (HR per 5.0-U difference, 0.88; 95% CI, 0.86-0.91). The inverse associations were observed even among nonoverweight women. There was a 4.2-fold risk gradient between the highest and lowest BMI categories (BMI≥35.0 vs |
| Document Type: |
article in journal/newspaper |
| Language: |
English |
| Relation: |
https://doi.org/10.1001/jamaoncol.2018.1771 |
| DOI: |
10.1001/jamaoncol.2018.1771 |
| Availability: |
https://doi.org/10.1001/jamaoncol.2018.1771; https://ora.ox.ac.uk/objects/uuid:7ed1e497-cf3d-4644-ab8e-a9ad130559d2 |
| Rights: |
info:eu-repo/semantics/openAccess ; CC Attribution (CC BY) |
| Accession Number: |
edsbas.E27E2475 |
| Database: |
BASE |