title: Association of Urinary Sodium Excretion With Blood Pressure and Cardiovascular Clinical Events in 17,033 Latin Americans.
abstract: Information on actual sodium intake and its relationships with blood pressure (BP) and clinical events in South America is limited. The aim of this cohort study was to assess the relationship of sodium intake with BP, cardiovascular (CV) events, and mortality in South America.
  
  
  
  We studied 17,033 individuals, aged 35-70 years, from 4 South American countries (Argentina, Brazil, Chile, and Colombia). Measures of sodium excretion, estimated from morning fasting urine, were used as a surrogate for daily sodium intake. We measured BP and monitored the composite outcome of death and major CV events.
  
  
  
  Overall mean sodium excretion was 4.70±1.43g/day. A positive, nonuniform association between sodium and BP was detected, with a significant steeper slope for the relationship at higher sodium excretion levels (P < 0.001 for interaction). With a median follow-up of 4.7 years, the primary composite outcome (all-cause death, myocardial infarction, stroke, or heart failure) occurred in 568 participants (3.4%). Compared with sodium excretion of 5-6g/day (reference group), participants who excreted >7g/day had increased risks of the primary outcome (odds ratio (OR) 1.73; 95% confidence interval (CI) 1.24 to 2.40; P < 0.001), as well as death from any cause (OR 1.87; 95% CI 1.23 to 2.83; P = 0.003) and major CV disease (OR 1.77; 95% CI 1.12 to 2.81; P = 0.014). Sodium excretion of <3g/day was associated with a statistically nonsignificant increased risk of the primary outcome (OR 1.20; 95% CI 0.86 to 1.65; P = 0.26) and death from any cause (OR 1.25; 95% CI 0.81 to 1.93; P = 0.29), and a significant increased risk of major CV disease (OR 1.50; 95% CI 1.01 to 2.24; P = 0.048), as compared to the reference group.
  
  
  
  Our results support a positive, nonuniform association between estimated urinary sodium excretion and BP, and a possible J-shaped pattern of association between sodium excretion over the entire range and clinical outcomes.
authors.affiliation: The Population Health Research Institute, Hamilton Health Sciences, McMaster University, Hamilton, ON, Canada; pablo.lamelas@phri.ca.
authors.forename: Pablo M
authors.initials: PM
authors.lastname: Lamelas
authors.affiliation: The Population Health Research Institute, Hamilton Health Sciences, McMaster University, Hamilton, ON, Canada; Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada;
authors.forename: Andrew
authors.initials: A
authors.lastname: Mente
authors.affiliation: Department of Laboratory Medicine, McMaster University, Hamilton, ON, Canada; Estudios Clínicos Latinoamérica, Rosario, Argentina;
authors.forename: Rafael
authors.initials: R
authors.lastname: Diaz
authors.affiliation: Department of Laboratory Medicine, McMaster University, Hamilton, ON, Canada; Estudios Clínicos Latinoamérica, Rosario, Argentina;
authors.forename: Andres
authors.initials: A
authors.lastname: Orlandini
authors.affiliation: Dante Pazzanese Institute of Cardiology, São Paulo, Brazil;
authors.forename: Alvaro
authors.initials: A
authors.lastname: Avezum
authors.affiliation: Dante Pazzanese Institute of Cardiology, São Paulo, Brazil;
authors.forename: Gustavo
authors.initials: G
authors.lastname: Oliveira
authors.affiliation: Universidad de la Frontera, Temuco, Chile;
authors.forename: Fernando
authors.initials: F
authors.lastname: Lanas
authors.affiliation: Universidad de la Frontera, Temuco, Chile;
authors.forename: Pamela
authors.initials: P
authors.lastname: Seron
authors.affiliation: Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada; Fundación Oftalmológica de Santander Medical School, Universidad de Santander, Floridablanca, Colombia;
authors.forename: Patricio
authors.initials: P
authors.lastname: Lopez-Jaramillo
authors.affiliation: Fundación Oftalmológica de Santander Medical School, Universidad de Santander, Floridablanca, Colombia;
authors.forename: Paul
authors.initials: P
authors.lastname: Camacho-Lopez
authors.affiliation: The Population Health Research Institute, Hamilton Health Sciences, McMaster University, Hamilton, ON, Canada; Department of Medicine, McMaster University, Hamilton, ON, Canada.
authors.forename: Martin J
authors.initials: MJ
authors.lastname: O Donnell
authors.affiliation: The Population Health Research Institute, Hamilton Health Sciences, McMaster University, Hamilton, ON, Canada;
authors.forename: Sumathy
authors.initials: S
authors.lastname: Rangarajan
authors.affiliation: The Population Health Research Institute, Hamilton Health Sciences, McMaster University, Hamilton, ON, Canada; Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada; Department of Medicine, McMaster University, Hamilton, ON, Canada.
authors.forename: Koon
authors.initials: K
authors.lastname: Teo
authors.affiliation: The Population Health Research Institute, Hamilton Health Sciences, McMaster University, Hamilton, ON, Canada; Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, ON, Canada; Department of Medicine, McMaster University, Hamilton, ON, Canada.
authors.forename: Salim
authors.initials: S
authors.lastname: Yusuf
mesh_terms: D000328:Adult; D000368:Aged; D001794:Blood Pressure; D002318:Cardiovascular Diseases / Q000401:mortality / Q000652:urine*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012964:Sodium / Q000652:urine*; D013020:South America / Q000453:epidemiology
chemical_list: D012964:Sodium
keywords: blood pressure; cardiovascular disease; hypertension; mortality.; sodium intake