Association between body mass index and incidence of breast cancer in premenopausal women: A Japanese nationwide database study

Abstract

Purpose: The association between body mass index (BMI) and the incidence of premenopausal breast cancer in the Asian population remains unclear. We investigated this association using data from a Japanese nationwide administrative database.Methods: We retrospectively identified 785,703 females aged <45 years with available health checkup data on BMI from January 2005 and April 2020 from a Japanese nationwide database. Cox proportional hazards model was used to estimate hazard ratios for breast cancer (total breast cancer, breast cancer with hormonal drug and trastuzumab administration, and breast cancer by age ≤45 years) associated with BMI recorded at the first health checkup. We conducted restricted cubic spline analysis without BMI categorization to investigate potential nonlinear associations with adjustment for backgrounds such as smoking and alcohol consumption.Results: Overall, the median BMI was 20.5 (interquartile range [IQR], 18.9–22.7) kg/m2, and the median age was 37 (IQR, 29–41) years. Breast cancer occurred in 5597 participants (0.71%) at a median age of 44 (IQR, 42–46) years during a median follow-up of 1034 (IQR, 634–1779) days. A BMI of ≥22.0 kg/m2 was significantly associated with lower incidences of total breast cancer, breast cancer with hormonal drug administration, and breast cancer by age ≤45 years, whereas no significant associations were observed for breast cancer with trastuzumab administration. Conclusion: This study, which used a Japanese nationwide database, demonstrated that BMI was inversely associated with premenopausal breast cancer development in East Asian women, similar to that observed in Western women.

Analysis of Status and Risk Factors of Disease Progression in Female Breast Cancer Patients in Liuzhou, China

“…In the current study, no relevant studies have reported the distribution characteristics of BMI, blood glucose and blood pressure in breast cancer patients. However, it has been pointed out that BMI can affect the occurrence, development and prognosis of breast cancer to a certain extent, or it is an independent risk factor for postoperative hyperlipidemia in patients with invasive breast cancer, and it is also closely related to the clinical characteristics of patients [12][13][14]. The reason for the failure to obtain consistent results in this study may be that only 26 patients (11.5%) with BMI ≥28 kg/m2 did not reach 15% of the total sample size, which resulted in insufficient confidence in the conclusions obtained and failed to find associations with patients' pathological characteristics and disease progression, so if we want to further substantiate this point of view, this study still needs a larger sample population to Therefore, in order to further confirm this idea, this study still needs a larger sample population for further clarification.…”