Yi-Xin Wang1,2, Mariel Arvizu1, Janet W Rich-Edwards3,4, JoAnn E Manson3,5,6, Liang Wang7, Stacey A Missmer3,8, Jorge E Chavarro1,3,5. 1. Department of Nutrition, Harvard T.H. Chan School of Public Health, Boston, MA, USA. 2. Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, MA, USA. 3. Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA. 4. Division of Women's Health, Department of Medicine, Brigham and Women's Hospital, Harvard Medical School, USA. 5. Channing Division of Network Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA. 6. Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA. 7. Department of Public Health, Robbins College of Health and Human Sciences, Baylor University, Waco, TX, USA. 8. Department of Obstetrics, Gynecology and Reproductive Biology, College of Human Medicine, Michigan State University, Grand Rapids, MI, USA.
Abstract
Background: Breastfeeding has been associated with a reduced maternal long-term risk of chronic diseases, but its association with mortality is poorly known. Methods: We included 166,708 female United States (US) nurses from the Nurses' Health Study (1986-2016) and the Nurses' Health Study II (1989-2019) who experienced at least one pregnancy lasting at least six months across their reproductive lifespan. Hazard ratios and 95% confidence intervals (CI) for mortality according to lifetime breastfeeding duration were estimated with time-dependent Cox proportional hazards regression models. Findings: During 4,705,160 person-years of follow-up, 36,634 deaths were documented in both cohorts, including 9880 from cancer and 7709 from cardiovascular disease (CVD). Lifetime total breastfeeding duration was associated with a lower subsequent risk of all-cause mortality in a non-linear manner (p-value for non-linearity=0.0007). The pooled multivariable-adjusted hazard ratios of all-cause mortality were 0.95 (95% CI: 0.92 to 0.98), 0.94 (95% CI: 0.91 to 0.98), 0.93 (95% CI: 0.90 to 0.97), and 0.93 (95% CI: 0.89 to 0.97), respectively, for women reporting lifetime total breastfeeding duration of 4-6, 7-11, 12-23, and ≥24 months, compared to women who breastfed for ≤3 months over their reproductive lifespan. Cause-specific analysis showed a similar pattern of non-linear inverse associations between lifetime total breastfeeding duration and CVD and cancer mortality (both p-values for non-linearity <0.01). There was no evidence of interactions between breastfeeding duration and pre-pregnancy lifestyle factors on mortality risk. Interpretation: Parous women with longer lifetime breastfeeding duration had a modestly lower risk of mortality. Funding: The National Institutes of Health grants.
Background: Breastfeeding has been associated with a reduced maternal long-term risk of chronic diseases, but its association with mortality is poorly known. Methods: We included 166,708 female United States (US) nurses from the Nurses' Health Study (1986-2016) and the Nurses' Health Study II (1989-2019) who experienced at least one pregnancy lasting at least six months across their reproductive lifespan. Hazard ratios and 95% confidence intervals (CI) for mortality according to lifetime breastfeeding duration were estimated with time-dependent Cox proportional hazards regression models. Findings: During 4,705,160 person-years of follow-up, 36,634 deaths were documented in both cohorts, including 9880 from cancer and 7709 from cardiovascular disease (CVD). Lifetime total breastfeeding duration was associated with a lower subsequent risk of all-cause mortality in a non-linear manner (p-value for non-linearity=0.0007). The pooled multivariable-adjusted hazard ratios of all-cause mortality were 0.95 (95% CI: 0.92 to 0.98), 0.94 (95% CI: 0.91 to 0.98), 0.93 (95% CI: 0.90 to 0.97), and 0.93 (95% CI: 0.89 to 0.97), respectively, for women reporting lifetime total breastfeeding duration of 4-6, 7-11, 12-23, and ≥24 months, compared to women who breastfed for ≤3 months over their reproductive lifespan. Cause-specific analysis showed a similar pattern of non-linear inverse associations between lifetime total breastfeeding duration and CVD and cancer mortality (both p-values for non-linearity <0.01). There was no evidence of interactions between breastfeeding duration and pre-pregnancy lifestyle factors on mortality risk. Interpretation: Parous women with longer lifetime breastfeeding duration had a modestly lower risk of mortality. Funding: The National Institutes of Health grants.
Authors: Satyajit K Karnik; Hainan Chen; Graeme W McLean; Jeremy J Heit; Xueying Gu; Andrew Y Zhang; Magali Fontaine; Michael H Yen; Seung K Kim Journal: Science Date: 2007-11-02 Impact factor: 47.728
Authors: Renée T Fortner; Julia Sisti; Boyang Chai; Laura C Collins; Bernard Rosner; Susan E Hankinson; Rulla M Tamimi; A Heather Eliassen Journal: Breast Cancer Res Date: 2019-03-12 Impact factor: 6.466