title: Associations of intakes of magnesium and calcium and survival among women with breast cancer: results from Western New York Exposures and Breast Cancer (WEB) Study.
abstract: Magnesium (Mg) and calcium (Ca) antagonizes each other in (re) absorption, cell cycle regulation, inflammation, and many other physiologic activities. However, few studies have investigated the association between magnesium and calcium intakes and breast cancer survival, and the interaction between calcium and magnesium intake. In a cohort of 1,170 women with primary, incident, and histologically confirmed breast cancer from Western New York State, we examined the relationship between intakes of these two minerals and survival. Cox regression models were used to estimate hazard ratios (HR) and 95% confidence intervals (95% CI). Mean follow-up time was 87.4 months after breast cancer diagnosis; there were 170 deaths identified. After adjustment for known prognostic factors, and intakes of energy, total vitamin D and total calcium, higher dietary intake of magnesium was inversely associated with risk of all-cause mortality (HR = 0.50, 95% CI, 0.28-0.90 for highest vs. lowest tertile; p trend = 0.02). Likewise, a marginal association was found for total Magnesium intake from foods and supplements combined (HR = 0.58, 95% CI, 0.31-1.08; p trend = 0.09). The inverse association of higher total magnesium intake with all-cause mortality was primarily presented among postmenopausal women and was stronger among women who had a high Ca:Mg intake ratio (>2.59). There were no clear associations for prognosis with intake of calcium. We found that magnesium intake alone may improve overall survival following breast cancer, and the association may be stronger among those with high Ca:Mg intake ratio.
authors.affiliation: Department of Biostatistics and Epidemiology, School of Public Health, University of North Texas Health Science Center Fort Worth, TX 76107, USA.
authors.forename: Meng-Hua
authors.initials: MH
authors.lastname: Tao
authors.affiliation: Vanderbilt Epidemiology Center, University of Vanderbilt Nashville, TN 37203, USA.
authors.forename: Qi
authors.initials: Q
authors.lastname: Dai
authors.affiliation: Department of Epidemiology and Environmental Health, School of Public Health and Health Professions, University at Buffalo Buffalo, NY 14214, USA.
authors.forename: Amy E
authors.initials: AE
authors.lastname: Millen
authors.affiliation: Department of Epidemiology and Environmental Health, School of Public Health and Health Professions, University at Buffalo Buffalo, NY 14214, USA.
authors.forename: Jing
authors.initials: J
authors.lastname: Nie
authors.affiliation: Baptist Cancer Center Memphis, TN 38120, USA.
authors.forename: Stephen B
authors.initials: SB
authors.lastname: Edge
authors.affiliation: City College of New York New York, NY 10031, USA.
authors.forename: Maurizio
authors.initials: M
authors.lastname: Trevisan
authors.affiliation: Ohio State University Comprehensive Cancer Center, The Ohio State University Columbus, OH 43210, USA.
authors.forename: Peter G
authors.initials: PG
authors.lastname: Shields
authors.affiliation: Department of Epidemiology and Environmental Health, School of Public Health and Health Professions, University at Buffalo Buffalo, NY 14214, USA.
authors.forename: Jo L
authors.initials: JL
authors.lastname: Freudenheim
keywords: Magnesium; breast cancer survival; calcium; epidemiology