title: North Central Cancer Treatment Group N10C2 (Alliance): a double-blind placebo-controlled study of magnesium supplements to reduce menopausal hot flashes.
abstract: OBJECTIVE
  Hot flashes are a common symptom in breast cancer survivors that can negatively impact quality of life. Preliminary data suggested that magnesium might be used as an effective low-cost treatment of hot flashes with minimal adverse effects.
  
  
  METHODS
  A four-arm, double-blind, placebo-controlled, randomized trial was conducted. Postmenopausal women with a history of breast cancer and bothersome hot flashes were randomized into treatment groups of magnesium oxide 800 or 1,200 mg daily or corresponding placebo groups at a 2:2:(1:1) ratio. Hot flash frequency and hot flash score (number × mean severity) were measured using a validated hot flash diary. A 1-week baseline period preceded initiation of study medication. The primary endpoint was intrapatient difference in mean hot flash score between baseline and treatment periods, comparing each magnesium group with the combined placebo groups using a gatekeeping procedure. Results were analyzed using repeated-measures and growth curve models on weekly hot flash scores based on a modified intent-to-treat principle.
  
  
  RESULTS
  Two hundred eighty-nine women enrolled between December 2011 and March 2013. Study groups were well balanced for baseline characteristics. Mean hot flash scores, mean hot flash frequencies, and associated changes during the treatment period were similar for each group. An increased incidence of diarrhea and a corresponding lower incidence of constipation were reported in magnesium arms compared with placebo. No statistically significant difference in other toxicities or quality-of-life measures was observed.
  
  
  CONCLUSIONS
  The results of this trial do not support the use of magnesium oxide for hot flashes.
authors.affiliation: From the 1Virginia Commonwealth University, Richmond, VA; 2Alliance Statistics and Data Center, Mayo Clinic Rochester, Rochester, MN; 3Johns Hopkins Medical Institutions, Baltimore, MD; 4University of Michigan School of Nursing, Ann Arbor, MI; 5Colorado Cancer Research Program, Denver, CO; 6Wichita Community Clinical Oncology Program, Wichita, KS; 7Metro-Minnesota Community Clinical Oncology Program, St Louis Park, MN; 8Michigan Cancer Research Consortium, Ann Arbor, MI; 9Illinois Oncology Research Association Community Clinical Oncology Program, Peoria, IL; 10Grand Rapids Clinical Oncology Program, Grand Rapids, MI; and 11Mayo Clinic, Rochester, MN.
authors.forename: Haeseong
authors.initials: H
authors.lastname: Park
authors.forename: Rui
authors.initials: R
authors.lastname: Qin
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Smith
authors.forename: Pamela J
authors.initials: PJ
authors.lastname: Atherton
authors.forename: Debra L
authors.initials: DL
authors.lastname: Barton
authors.forename: Keren
authors.initials: K
authors.lastname: Sturtz
authors.forename: Shaker R
authors.initials: SR
authors.lastname: Dakhil
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Anderson
authors.forename: Kathleen
authors.initials: K
authors.lastname: Flynn
authors.forename: Suneetha
authors.initials: S
authors.lastname: Puttabasavaiah
authors.forename: Nguyet Anh
authors.initials: NA
authors.lastname: Le-Lindqwister
authors.forename: Gilbert D A
authors.initials: GD
authors.lastname: Padula
authors.forename: Charles L
authors.initials: CL
authors.lastname: Loprinzi
mesh_terms: D001943:Breast Neoplasms / Q000150:complications / Q000188:drug therapy*; D019587:Dietary Supplements; D004311:Double-Blind Method; D005260:Female; D019584:Hot Flashes / Q000139:chemically induced / Q000188:drug therapy*; D006801:Humans; D008277:Magnesium Oxide / Q000627:therapeutic use*; D008593:Menopause; D008875:Middle Aged; D011788:Quality of Life; D016896:Treatment Outcome
chemical_list: D008277:Magnesium Oxide