title: Normal values of serum IGF-1 in adults: results from a Brazilian population.
abstract: OBJECTIVE
  To determine the normal values of serum IGF-1 (Immulite 2000) in a Brazilian adult (21-70 years) population.
  
  
  METHODS
  Healthy volunteers were divided into 10 groups according to age (5-year intervals), with 100 subjects (50 men and 50 women) per group. One-hundred participants were selected for repetition of the test after 12 weeks.
  
  
  RESULTS
  No difference in IGF-1 values was observed between men and women, but a progressive reduction of serum IGF-1 with age was seen. The reference values provided by the manufacturer of the assay, although discretely higher, were very close to the values found in this study. A second measurement of IGF-1 after 12 weeks revealed a variation < 20% in 99% of subjects.
  
  
  CONCLUSIONS
  This study established the reference range for IGF-1 determined with the Immulite 2000 assay for a large number of healthy Brazilian adults stratified according to age, and suggests that variations > 20% in IGF-1 levels within an interval of 12 weeks cannot be attributed to interassay variability.
authors.affiliation: Santa Casa de Belo Horizonte, Departamento de Neuroendocrinologia, Santa Casa de Belo Horizonte, MG, Brazil. pedrorosario@globo.com
authors.forename: Pedro Weslley
authors.initials: PW
authors.lastname: Rosario
mesh_terms: D000328:Adult; D000368:Aged; D001938:Brazil; D005260:Female; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D012737:Sex Factors; D055815:Young Adult
chemical_list: D007334:Insulin-Like Growth Factor I