title: Risk factors associated with a decreased estimated glomerular filtration rate based on cystatin C levels in school-age children with extremely low birthweight.
abstract: OBJECTIVE
  A single centre retrospective cohort study was designed to investigate the estimated glomerular filtration rate (eGFR) in school-age children born with extremely low birthweight (ELBW) and to determine risk factors predictive of decreased eGFR.
  
  
  METHODS
  We compared eGFR based on cystatin C (CysC-eGFR) between school-age children born with ELBW (ELBW group, n = 48; median gestational age: 26.9 weeks; median birthweight: 792 g) and children born at term (control group, n = 48). The ELBW group was then further divided into a decreased CysC-eGFR subgroup (eGFR <90 mL/min per 1.73 m2, n = 20) and a normal CysC-eGFR subgroup (n = 28), and perinatal background factors were compared.
  
  
  RESULTS
  The ELBW group showed a significantly lower CysC-eGFR compared with the control group (P < 0.001). Comparison between the decreased and normal CysC-eGFR subgroups in the ELBW group showed that children with lower birthweight, shorter gestational age, lower 5-min Apgar score, longer length of mechanical ventilation, lower weight gain in the first 11 weeks, chronic lung disease, and postnatal corticosteroid administration had significantly decreased CysC-eGFR. Multivariate logistic regression showed that a lower 5-min Apgar score was the only independent risk factor for decreased CysC-eGFR.
  
  
  CONCLUSIONS
  CysC-eGFR might already be decreased at school age in children born with ELBW. Renal assessment in regular follow-up examinations is recommended.
authors.affiliation: Department of Pediatric Nephrology and Metabolism, Osaka Medical Center and Research Institute for Maternal and Child Health, Izumi, Japan.
authors.forename: Natsumi
authors.initials: N
authors.lastname: Yamamura-Miyazaki
authors.affiliation: Department of Pediatric Nephrology and Metabolism, Osaka Medical Center and Research Institute for Maternal and Child Health, Izumi, Japan.
authors.forename: Katsusuke
authors.initials: K
authors.lastname: Yamamoto
authors.affiliation: Department of Pediatric Nephrology and Metabolism, Osaka Medical Center and Research Institute for Maternal and Child Health, Izumi, Japan.
authors.forename: Kaori
authors.initials: K
authors.lastname: Fujiwara
authors.affiliation: Department of Pediatric Nephrology and Metabolism, Osaka Medical Center and Research Institute for Maternal and Child Health, Izumi, Japan.
authors.forename: Yoko
authors.initials: Y
authors.lastname: Santo
authors.affiliation: Department of Pediatric Nephrology and Metabolism, Osaka Medical Center and Research Institute for Maternal and Child Health, Izumi, Japan.|Department of Bone and Mineral Research, Osaka Medical Center and Research Institute for Maternal and Child Health, Izumi, Japan.
authors.forename: Toshimi
authors.initials: T
authors.lastname: Michigami
authors.affiliation: Department of Neonatology, Osaka Medical Center and Research Institute for Maternal and Child Health, Izumi, Japan.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Kitajima
authors.affiliation: Department of Pediatric Nephrology and Metabolism, Osaka Medical Center and Research Institute for Maternal and Child Health, Izumi, Japan.
authors.forename: Kenichi
authors.initials: K
authors.lastname: Satomura
mesh_terms: D001724:Birth Weight; D016022:Case-Control Studies; D002648:Child; D055316:Cystatin C / Q000097:blood*; D005260:Female; D005865:Gestational Age; D005919:Glomerular Filtration Rate; D006801:Humans; D052577:Infant, Extremely Low Birth Weight; D007674:Kidney Diseases / Q000097:blood* / Q000209:etiology*; D008297:Male; D012189:Retrospective Studies; D012307:Risk Factors
chemical_list: D055316:Cystatin C
keywords: Apgar score; chronic kidney disease; cystatin C; estimated glomerular filtration rate; extremely low birthweight