title: Weight at birth and infancy in relation to adult leukocyte count: a population-based study of 5619 men and women followed from the fetal period to adulthood.
abstract: BACKGROUND
  Impaired fetal growth is associated with increased risk for coronary heart disease and diabetes in adulthood, but the underlying mechanism is unclear.
  
  
  OBJECTIVE
  The objective of the study was to examine the relation between early growth (weight at birth and first year) and adult total leukocyte count, the primary cell effectors of inflammation.
  
  
  METHODS
  This was a birth cohort study (Northern Finland Birth Cohort 1966) with participants prospectively and longitudinally followed up from birth to age 31 yr.
  
  
  METHODS
  This was a general population-based cohort in Finland.
  
  
  METHODS
  A total of 5619 offspring of expectant mothers who attended a clinical examination and blood draw at 31-yr follow-up (4486 with complete data on weight at 1 yr) participated in the study. MAIN EXPOSURE VARIABLES: Weight at birth and at 1 year.
  
  
  METHODS
  Absolute leukocyte count was measured.
  
  
  RESULTS
  Total leukocyte count was lower at higher birth weight categories with or without adjustments for adult systolic blood pressure, total cholesterol, fasting insulin, body mass index, cigarette smoking, sex, gestational age, and other life course factors. The covariate-adjusted regression coefficient for log-transformed total leukocyte count (x 10(9) cells/liter) per 1 SD (525 g) increase in birth weight was -0.012 (95% confidence interval -0.021 to -0.004). The association persisted, even when limiting our analyses among healthy and nonsmoking individuals, and the inversely linear relation was steepest among those with lower weight attained at 1 yr (P for interaction = 0.027).
  
  
  CONCLUSIONS
  Poorer growth in early life was associated with systemic low-grade inflammation in adulthood. This relation suggests a plausible inflammatory mechanism linking early growth impairment with risk of coronary heart disease and diabetes later in life.
authors.affiliation: Institute of Health Sciences, University of Oulu, Oulu 90014, Finland. dexter.canoy@manchester.ac.u
authors.forename: Dexter
authors.initials: D
authors.lastname: Canoy
authors.forename: Anneli
authors.initials: A
authors.lastname: Pouta
authors.forename: Aimo
authors.initials: A
authors.lastname: Ruokonen
authors.forename: Anna-Liisa
authors.initials: AL
authors.lastname: Hartikainen
authors.forename: Pekka
authors.initials: P
authors.lastname: Saikku
authors.forename: Marjo-Riitta
authors.initials: MR
authors.lastname: Järvelin
mesh_terms: D000293:Adolescent; D000328:Adult; D032721:Adult Children; D001724:Birth Weight / Q000502:physiology*; D002648:Child; D002657:Child Development / Q000502:physiology*; D002675:Child, Preschool; D015331:Cohort Studies; D005260:Female; D005312:Fetal Blood / Q000166:cytology; D005317:Fetal Growth Retardation / Q000097:blood / Q000503:physiopathology; D005387:Finland; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007958:Leukocyte Count; D008297:Male; D011153:Population; D011247:Pregnancy; D055815:Young Adult