title: Association between intakes of magnesium, potassium, and calcium and risk of stroke: 2 cohorts of US women and updated meta-analyses.
abstract: BACKGROUND
  Prospective data on the relation of magnesium, potassium, and calcium intakes with stroke risk are inconsistent, and to our knowledge, the effect of a combined mineral diet score has not been examined.
  
  
  OBJECTIVE
  We examined associations between intakes of magnesium, potassium, and calcium and risk of incident stroke in 86,149 women in the Nurses' Health Study (NHS) I and 94,715 women in the NHS II.
  
  
  METHODS
  In this prospective cohort study, we calculated HRs of stroke by quintiles of intake for each mineral and for a combined diet score of all 3 minerals by using multivariate Cox proportional hazard models. In addition, we updated meta-analyses on dietary intakes of these minerals and risk of stroke.
  
  
  RESULTS
  During follow-up (30 y in the NHS I; 22 y in the NHS II) a total of 3780 incident stroke cases were documented. Pooled multivariate RRs of total stroke for women in the highest compared with the lowest quintiles were 0.87 (95% CI: 0.78, 0.97) for total magnesium, 0.89 (95% CI: 0.80, 0.99) for total potassium, and 0.97 (95% CI: 0.87, 1.09) for total calcium intake. Pooled RRs for women in the highest compared with the lowest quintiles of a combined mineral diet score were 0.72 (95% CI: 0.65, 0.81) for total stroke, 0.78 (95% CI: 0.66, 0.92) for ischemic stroke, and 0.80 (95% CI: 0.61, 1.04) for hemorrhagic stroke. In the updated meta-analyses of all prospective studies to date, the combined RR of total stroke was 0.87 (95% CI: 0.83, 0.92) for a 100-mg/d increase in magnesium intake, 0.91 (95% CI: 0.88, 0.94) for a 1000-mg/d increase in potassium intake, and 0.98 (95% CI: 0.94, 1.02) for a 300-mg/d increase in calcium intake.
  
  
  CONCLUSIONS
  A combined mineral diet score was inversely associated with risk of stroke. High intakes of magnesium and potassium but not calcium were also significantly associated with reduced risk of stroke in women.
authors.affiliation: From the Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, MA (SNA and KMR); the Departments of Department of Nutrition (SNA, DS, and WCW), Biostatistics (DS), Epidemiology (DS and WCW), and Global Health and Population (DS), Harvard T.H. Chan School of Public Health, Boston, MA; and the Channing Division of Network Medicine, Boston, MA (WCW). sallya@mail.harvard.edu.
authors.forename: Sally N
authors.initials: SN
authors.lastname: Adebamowo
authors.affiliation: From the Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, MA (SNA and KMR); the Departments of Department of Nutrition (SNA, DS, and WCW), Biostatistics (DS), Epidemiology (DS and WCW), and Global Health and Population (DS), Harvard T.H. Chan School of Public Health, Boston, MA; and the Channing Division of Network Medicine, Boston, MA (WCW).
authors.forename: Donna
authors.initials: D
authors.lastname: Spiegelman
authors.affiliation: From the Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, MA (SNA and KMR); the Departments of Department of Nutrition (SNA, DS, and WCW), Biostatistics (DS), Epidemiology (DS and WCW), and Global Health and Population (DS), Harvard T.H. Chan School of Public Health, Boston, MA; and the Channing Division of Network Medicine, Boston, MA (WCW).
authors.forename: Walter C
authors.initials: WC
authors.lastname: Willett
authors.affiliation: From the Division of Preventive Medicine, Department of Medicine, Brigham and Women's Hospital, Boston, MA (SNA and KMR); the Departments of Department of Nutrition (SNA, DS, and WCW), Biostatistics (DS), Epidemiology (DS and WCW), and Global Health and Population (DS), Harvard T.H. Chan School of Public Health, Boston, MA; and the Channing Division of Network Medicine, Boston, MA (WCW).
authors.forename: Kathryn M
authors.initials: KM
authors.lastname: Rexrode
mesh_terms: D000328:Adult; D000368:Aged; D002136:Calcium, Dietary / Q000008:administration & dosage*; D004032:Diet; D004305:Dose-Response Relationship, Drug; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008274:Magnesium / Q000008:administration & dosage*; D008875:Middle Aged; D015999:Multivariate Analysis; D017419:Potassium, Dietary / Q000008:administration & dosage*; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D020521:Stroke / Q000453:epidemiology*; D011795:Surveys and Questionnaires; D014131:Trace Elements / Q000008:administration & dosage; D014481:United States / Q000453:epidemiology
chemical_list: D002136:Calcium, Dietary; D017419:Potassium, Dietary; D014131:Trace Elements; D008274:Magnesium
keywords: calcium; hemorrhagic stroke; ischemic stroke; magnesium; potassium; stroke