title: Gestational age at birth affects maturation of baroreflex control.
abstract: OBJECTIVE
  To assess the effect of prone sleeping, the major risk factor for sudden infant death syndrome, in the control of blood pressure (BP) in preterm infants born across a range of gestational ages.
  
  
  METHODS
  Daytime polysomnography was performed at 2-4 weeks, 2-3 months, and 5-6 months postterm age. The participants were 21 very preterm (mean gestation 29.4 ± 0.3 weeks), 14 preterm (mean gestation 33.1 ± 0.3 weeks), and 17 term (mean gestation 40.1 ± 0.3 weeks). BP was measured via a Finometer cuff (Finapres Medical Systems, Amsterdam, The Netherlands) placed around the wrist. Data were recorded both supine and prone. Baroreflex sensitivity (BRS) was calculated via cross-spectral analysis of spontaneous fluctuations in BP.
  
  
  RESULTS
  BRS was lower in the prone position in very preterm infants at 2-4 weeks in active sleep (P < .05). Maturation of BRS was delayed in very preterm compared with both preterm and term infants.
  
  
  CONCLUSIONS
  Maturation of BRS after term-equivalent age is altered in very preterm infants. Reduced BRS may result in an impaired ability of very preterm infants to respond to cardiovascular stress during infancy and may predispose them to cardiovascular disease later in life.
authors.affiliation: The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Victoria, Australia; The Department of Paediatrics, Monash University, Melbourne, Victoria, Australia.
authors.forename: Karinna L
authors.initials: KL
authors.lastname: Fyfe
authors.affiliation: The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Victoria, Australia; The Department of Paediatrics, Monash University, Melbourne, Victoria, Australia.
authors.forename: Stephanie R
authors.initials: SR
authors.lastname: Yiallourou
authors.affiliation: The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Victoria, Australia; The Department of Paediatrics, Monash University, Melbourne, Victoria, Australia; Monash Newborn, Monash Health, Melbourne, Victoria, Australia.
authors.forename: Flora Y
authors.initials: FY
authors.lastname: Wong
authors.affiliation: The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Victoria, Australia.
authors.forename: Alexsandria
authors.initials: A
authors.lastname: Odoi
authors.affiliation: The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Victoria, Australia.
authors.forename: Adrian M
authors.initials: AM
authors.lastname: Walker
authors.affiliation: The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Victoria, Australia; The Department of Paediatrics, Monash University, Melbourne, Victoria, Australia. Electronic address: rosemary.horne@monash.edu.
authors.forename: Rosemary S C
authors.initials: RS
authors.lastname: Horne
mesh_terms: D017704:Baroreflex / Q000502:physiology*; D005260:Female; D005865:Gestational Age; D006801:Humans; D015994:Incidence; D007223:Infant; D007230:Infant, Low Birth Weight; D007231:Infant, Newborn; D007234:Infant, Premature; D007235:Infant, Premature, Diseases / Q000503:physiopathology*; D008297:Male; D017286:Polysomnography; D016684:Prone Position; D012307:Risk Factors; D012890:Sleep / Q000502:physiology*; D013398:Sudden Infant Death / Q000453:epidemiology / Q000209:etiology*; D014739:Victoria / Q000453:epidemiology