title: Abnormal circadian blood pressure regulation in children born preterm.
abstract: OBJECTIVE
  To assess a possible relationship between prematurity and casual blood pressure (BP) by means of 24-hour ambulatory BP monitoring (ABPM).
  
  
  METHODS
  ABPM was performed in 41 children aged 5 to 17 years who were born prematurely with (n = 11) or without intrauterine growth restriction, and in 27 matched children who were born at term with a birth weight appropriate for gestational age.
  
  
  RESULTS
  Although BP did not differ between the preterm group and control subjects during the daytime, nocturnal standardized systolic BP was elevated (P < .05) and a lack of nocturnal decrease was more prevalent in the preterm children compared with the control subjects (73% versus 41%, P = .01). The difference was caused by a marked increase of nighttime systolic BP in the light-for-date children (1.17 +/- 0.61 standard deviation scores; P < .01), although preterm children with appropriate weight (0.33 +/- 1.00) were not different from control subjects (0.09 +/- 0.73). Nighttime BP standard deviation scores were closely correlated with standardized heart rate, compatible with a role of sympathetic hyperactivation.
  
  
  CONCLUSIONS
  Subtle abnormalities of BP regulation, indicated by a selective increase of nocturnal systolic BP, are present during childhood in subjects born prematurely, and are prominent in those with intrauterine growth restriction.
authors: Division of Pediatric Nephrology, University Hospital for Pediatric and Adolescent Medicine, Hacettepe University, Ankara, Turkey. ukavak@yahoo.com
authors: Umut Selda
authors: US
authors: Bayrakci
authors: Franz
authors: F
authors: Schaefer
authors: Ali
authors: A
authors: Duzova
authors: Sule
authors: S
authors: Yigit
authors: Aysin
authors: A
authors: Bakkaloglu
mesh_terms: D000293:Adolescent; D001794:Blood Pressure; D018660:Blood Pressure Monitoring, Ambulatory; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D002940:Circadian Rhythm; D005317:Fetal Growth Retardation / Q000503:physiopathology*; D006706:Homeostasis; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D007236:Infant, Small for Gestational Age; D016014:Linear Models; D016555:Matched-Pair Analysis; D012016:Reference Values; D018709:Statistics, Nonparametric