title: Renal function and systolic blood pressure in very-low-birth-weight infants 1-3 years of age.
abstract: BACKGROUND
  Preterm very-low-birth-weight (PT-VLBW) infants are at risk of an elevated systolic blood pressure (SBP) in infancy and adulthood; however, the pathogenesis remains unclear. Altered renal development or function may be associated with increased SBP, but their contribution in PT-VLBW is unknown.
  
  
  METHODS
  We determined renal function and its relationship to SBP in three groups of PT-VLBW at 1, 2, and 3 years of age, using serum cystatin-C to calculate the estimated glomerular filtration rate (eGFR).
  
  
  RESULTS
  Cystatin-C levels decreased from 0.84 ± 0.2 (SD) within the 1-year group to 0.70 ± 0.1 mg/l (±SD; P < 0.001) at 3 years and were unrelated to gender, fetal growth, and neonatal indomethacin exposure. eGFR rose from 121 ± 59 in the 1-year group to 138 ± 21 ml/min · 1.73 m(2) (P < 0.001) at 3 years. At 1 year, cystatin-C levels decreased with increasing SBP (P < 0.007), and infants with SBP ≥ 90 th% had lower cystatin-C and higher eGFR (P < 0.05). At 3 years, infants with lower birth weight (P < 0.03) and gestational age (P = 0.06) had reduced eGFR.
  
  
  CONCLUSIONS
  Preterm very-low-birth-weight infants demonstrate increasing renal function with advancing age. An elevated SBP and eGFR at 1 year suggests dysfunctional renal autoregulation and hyperfiltration, which may alter subsequent renal function and contribute to the lower eGFR seen at 3 years in infants with the lowest birth weight and gestational age.
authors: Division of Neonatal-Perinatal Medicine, Department of Pediatrics, University of Texas Southwestern Medical School at Dallas, 5323 Harry Hines Boulevard, Dallas, TX 75390-9002, USA.
authors: Joshua A
authors: JA
authors: Frankfurt
authors: Andrea F
authors: AF
authors: Duncan
authors: Roy J
authors: RJ
authors: Heyne
authors: Charles R
authors: CR
authors: Rosenfeld
mesh_terms: D001794:Blood Pressure / Q000502:physiology*; D002675:Child, Preschool; D055316:Cystatin C / Q000032:analysis / Q000097:blood; D005260:Female; D005919:Glomerular Filtration Rate / Q000502:physiology*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases; D019102:Infant, Very Low Birth Weight / Q000502:physiology*; D007668:Kidney / Q000503:physiopathology*; D008297:Male
chemical_list: D055316:Cystatin C