title: [Ionized calcium and magnesium as interdependent variables in blood pressure origin in healthy adolescents].
abstract: BACKGROUND
  Growing evidence indicates that diet divalent cations--ionized calcium (Ca) and magnesium (Mg)--and MN blood group polymorphism may be associated with essential arterial hypertension.
  
  
  OBJECTIVE
  To assess a possible relationship between serum ionized Ca and Mg and MN blood group polymorphism with blood pressure (BP) and body mass index (BMI).
  
  
  METHODS
  The study group consisted of 173 healthy adolescents, 96 female (55.5%) and 77 male (44.5%), with mean age of 13.0 +/- 1.7 years. Serum ionized Ca and Mg were determined by standardized methods based on detection by specific electrodes. MN blood group polymorphism was determined by immunoaglutination of erythrocytes with monoclonal antibodies. BP was evaluated based on AHA recommendations. BMI was calculated as weight divided by squared height (Kg/m2). The statistical method used was the Pearson correlation.
  
  
  RESULTS
  In this population no significant correlation was found from serum ionized Ca (mean: 1.07 +/- 0.06 mmol/L) and Mg (mean: 1.15 +/- 0.97 mmol/L) with systolic BP (mean: 113.1 +/- 10.7 mmHg) and diastolic BP (mean: 66.1 +/- 10.1 mmHg). In contrast there was an inverse correlation between the quotient ionized Mg/ionized Ca (0.45 +/- 0.05) and diastolic BP (p = 0.029; r = -0.381). A positive correlation was found between BMI (20.57 +/- 3.24 Kg/m2) and systolic BP (p = 0.007; r = 0.24) and diastolic BP (p = 0.016; r = 0.22). No correlation was found between ionized Ca, ionized Mg and BP with MN blood group polymorphism.
  
  
  CONCLUSIONS
  In this population of healthy adolescents there was a dependence between diastolic BP and serum ionized Mg/ionized Ca. There was no interindividual BP and ionized Ca and Mg variation dependent from genetic variation.
authors.affiliation: Laboratório de Genética da Faculdade de Medicina de Lisboa, Lisboa.
authors.forename: M João
authors.initials: MJ
authors.lastname: Marta
authors.forename: A Pereira
authors.initials: AP
authors.lastname: Da Silva
authors.forename: Samuel
authors.initials: S
authors.lastname: Llobet
authors.forename: Luís
authors.initials: L
authors.lastname: Sardinha
authors.forename: Manuel J
authors.initials: MJ
authors.lastname: Halpern
authors.forename: Maria José
authors.initials: MJ
authors.lastname: Laires
authors.forename: Ana M
authors.initials: AM
authors.lastname: Ferreira
authors.forename: M Pires
authors.initials: MP
authors.lastname: Bicho
mesh_terms: D000293:Adolescent; D000367:Age Factors; D001789:Blood Group Antigens / Q000235:genetics; D001794:Blood Pressure; D015992:Body Mass Index; D002118:Calcium / Q000097:blood*; D005260:Female; D006801:Humans; D007477:Ions / Q000097:blood; D008274:Magnesium / Q000097:blood*; D008297:Male; D011110:Polymorphism, Genetic
chemical_list: D001789:Blood Group Antigens; D007477:Ions; D008274:Magnesium; D002118:Calcium
vernacular_title: Cálcio e magnésio ionizados como variáveis interdependentes na génese da pressão arterial, em adolescentes saudáveis.