title: High blood pressure in 2.5-year-old children born extremely preterm.
abstract: OBJECTIVE
  Adolescents and young adults born preterm have elevated blood pressure (BP). The objective of this study was to investigate if BP is elevated at 2.5 years of age after an extremely preterm birth (EXPT).
  
  
  METHODS
  In a regional subset of the national population-based cohort Extremely Preterm Infants in Sweden Study, BP at 2.5 years of age was studied in 68 survivors of EXPT (gestational age: 23.6-26.9 weeks; mean ± SD birth weight: 810 ± 164 g), and 65 matched controls born at term.
  
  
  RESULTS
  At follow-up at 2.5 years of corrected age, EXPT children had significantly higher systolic blood pressure (SBP) and diastolic blood pressure (DBP) z scores than controls born at term, according to pediatric BP nomograms by age, gender, and height. The proportion of SBP ≥90th percentile was 44% (30 of 68) in EXPT children and 23% (15 of 65) in controls (P = .01). In logistic regression analyses stratified according to gender, EXPT was associated with an odds ratio for a SBP ≥90th percentile of 3.32 (95% confidence interval: 1.25-8.81) among boys. The corresponding odds ratio among EXPT girls was 2.18 (95% confidence interval: 0.62-7.61). In EXPT children, SBP and DBP z scores were inversely correlated to catch-up growth from 36 weeks' postmenstrual age to follow-up at 2.5 years of age.
  
  
  CONCLUSIONS
  Children born extremely preterm have elevated office SBP and DBP at a corrected age of 2.5 years. This finding might have implications for their cardiovascular health later in life.
authors.affiliation: Department of Women's and Children's Health, Karolinska Institutet, Stockholm, Sweden. anna-karin.edstedt.bonamy@ki.se
authors.forename: Anna-Karin Edstedt
authors.initials: AK
authors.lastname: Bonamy
authors.forename: Karin
authors.initials: K
authors.lastname: Källén
authors.forename: Mikael
authors.initials: M
authors.lastname: Norman
mesh_terms: D000886:Anthropometry; D001794:Blood Pressure; D002675:Child, Preschool; D015331:Cohort Studies; D015897:Comorbidity; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006339:Heart Rate; D006801:Humans; D006973:Hypertension / Q000453:epidemiology*; D015994:Incidence; D007223:Infant; D052577:Infant, Extremely Low Birth Weight; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000453:epidemiology*; D008297:Male; D016017:Odds Ratio; D012737:Sex Factors; D013548:Sweden