title: Blood pressure and urinary excretion of electrolytes in Spanish schoolchildren.
abstract: Despite the importance of hypertension in adults, its effects on child health are poorly understood. This cross-sectional epidemiological study was designed to look for a relationship between elevated blood pressure (BP) in children and 24-h urinary excretion of sodium (Na) and potassium (K), and between BP and dietary salt intake. The study population was all 59 856 schoolchildren aged 6 to 14 years in the province of Almería in southern Spain, among whom 613 participants were chosen randomly for study. We measured 24-h urinary Na and K concentrations, systolic and diastolic BP, body weight and height. There was a weak correlation between Na excretion and systolic BP (r = 0.18, 95% confidence interval 0.10-0.26), and between K excretion and systolic BP (r = 0.49, 95% CI = 0.04-0.20). Body weight was the variable that best correlated with systolic (r = 0.49, 95% CI = 0.43-0.55) and diastolic BP, and with Na excretion (r = 0.48, 95% CI = 0.42-0.55). Multiple regression analysis also showed that body weight was the variable that best correlated with systolic BP (b = 0.58), although the variables in the equation explained little of the total variability in BP (26%). These correlations were significant at P < 0.05. In conclusion urinary electrolytes correlated poorly with BP in a sample of Spanish schoolchildren. Body weight was the only variable that showed a weak relationship with BP and Na excretion.
authors.affiliation: Hypertension Unit, University Hospital of Granada, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Maldonado-Martín
authors.forename: L
authors.initials: L
authors.lastname: García-Matarín
authors.forename: B
authors.initials: B
authors.lastname: Gil-Extremera
authors.forename: C
authors.initials: C
authors.lastname: Avivar-Oyonarte
authors.forename: M E
authors.initials: ME
authors.lastname: García-Granados
authors.forename: F
authors.initials: F
authors.lastname: Gil-García
authors.forename: J
authors.initials: J
authors.lastname: Latorre-Hernández
authors.forename: J
authors.initials: J
authors.lastname: Miró-Gutiérrez
authors.forename: A
authors.initials: A
authors.lastname: Soria-Bonilla
authors.forename: J
authors.initials: J
authors.lastname: Vergara-Martín
authors.forename: M R
authors.initials: MR
authors.lastname: Javier-Martínez
mesh_terms: D000293:Adolescent; D001794:Blood Pressure / Q000502:physiology*; D001827:Body Height / Q000502:physiology; D001835:Body Weight / Q000502:physiology; D002648:Child; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D006973:Hypertension / Q000453:epidemiology* / Q000503:physiopathology / Q000652:urine; D008297:Male; D011188:Potassium / Q000652:urine*; D012964:Sodium / Q000652:urine*; D012982:Sodium, Dietary / Q000008:administration & dosage*; D013030:Spain / Q000453:epidemiology; D013997:Time Factors; D014883:Water-Electrolyte Imbalance / Q000453:epidemiology* / Q000503:physiopathology / Q000652:urine
chemical_list: D012982:Sodium, Dietary; D012964:Sodium; D011188:Potassium