title: Body mass index and risk of breast cancer: a nonlinear dose-response meta-analysis of prospective studies.
abstract: The role of Body Mass Index (BMI) for Breast Cancer (BC) remains to be great interest for a long time. However, the precise effect of nonlinear dose-response for BMI and BC risk is still unclear. We conducted a dose-response meta-analysis to quantitatively assess the effect of BMI on BC risk. Twelve prospective studies with 4,699 cases identified among 426,199 participants and 25 studies of 22,809 cases identified among 1,155,110 participants in premenopausal and postmenopausal groups, respectively, were included in this meta-analysis. Significant non-linear dose-response (P < 0.001) association was identified between BMI and BC risk in postmenopausal women. Individuals with BMI of 25, 30, and 35 kg/m(2) yielded relative risks (RRs) of 1.02 [95% confidence interval (CI): 0.98-1.06], 1.12 (95% CI: 1.01-1.24), and 1.26 (95% CI: 1.07-1.50), respectively, when compared to the mean level of the normal BMI range. However, inverse result though not significant was observed in premenopausal women. In conclusion, the results of this meta-analysis highlighted that obesity contributed to increased BC risk in a nonlinear dose-response manner in postmenopausal women, and it is important to realize that body weight control may be a crucial process to reduce BC susceptibility.
authors.affiliation: Clinical Laboratory of the Fourth Affiliated Hospital, Zhejiang University School of Medicine, Yiwu, 322000, Zhejiang Province, China.
authors.forename: Xiaoping
authors.initials: X
authors.lastname: Xia
authors.affiliation: State Key Laboratory of Environment Health (Incubation), MOE (Ministry of Education) Key Laboratory of Environment &Health, Ministry of Environmental Protection Key Laboratory of Environment and Health (Wuhan), and Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Environment Health (Incubation), MOE (Ministry of Education) Key Laboratory of Environment &Health, Ministry of Environmental Protection Key Laboratory of Environment and Health (Wuhan), and Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Jiaoyuan
authors.initials: J
authors.lastname: Li
authors.affiliation: State Key Laboratory of Environment Health (Incubation), MOE (Ministry of Education) Key Laboratory of Environment &Health, Ministry of Environmental Protection Key Laboratory of Environment and Health (Wuhan), and Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Xueqin
authors.initials: X
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Environment Health (Incubation), MOE (Ministry of Education) Key Laboratory of Environment &Health, Ministry of Environmental Protection Key Laboratory of Environment and Health (Wuhan), and Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Rui
authors.initials: R
authors.lastname: Rui
authors.affiliation: State Key Laboratory of Environment Health (Incubation), MOE (Ministry of Education) Key Laboratory of Environment &Health, Ministry of Environmental Protection Key Laboratory of Environment and Health (Wuhan), and Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Cheng
authors.initials: C
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Environment Health (Incubation), MOE (Ministry of Education) Key Laboratory of Environment &Health, Ministry of Environmental Protection Key Laboratory of Environment and Health (Wuhan), and Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Guangdong Key Lab of Molecular Epidemiology and Department of Epidemiology and Biostatistics, School of Public Health, Guangdong Pharmaceutical University, Guangzhou, China.
authors.forename: Li
authors.initials: L
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Environment Health (Incubation), MOE (Ministry of Education) Key Laboratory of Environment &Health, Ministry of Environmental Protection Key Laboratory of Environment and Health (Wuhan), and Department of Epidemiology and Biostatistics, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Gong
authors.affiliation: Department of Medical Oncology, Cancer Institute and Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Yuan
mesh_terms: D015992:Body Mass Index; D001943:Breast Neoplasms / Q000209:etiology*; D005260:Female; D006801:Humans; D009765:Obesity / Q000150:complications*; D017697:Premenopause; D011446:Prospective Studies; D012307:Risk Factors