title: Insulin-like growth factor-1 is a predictor of blood haemoglobin concentration in 70-yr-old subjects.
abstract: The role of growth hormone (GH) for maintaining normal erythropoiesis among non-GH-deficient elderly subjects is not known.
  
  
  OBJECTIVE
  To determine relationships between the concentrations of serum insulin-like growth factor-1 (IGF-1) and it's carrier protein insulin-like growth factor binding protein 3 (IGFBP-3), as well as plasma erythropoietin (EPO), and blood haemoglobin (Hb) in elderly subjects.
  
  
  METHODS
  Serum IGF-1 and IGFBP-3 and plasma EPO were, in addition to basal haematological tests, measured in a community based representative population sample of 70-yr-olds (n = 619; 317 women and 302 men). Statistical analyses were made before and after exclusion of non-healthy subjects.
  
  
  RESULTS
  Mean IGF-1 concentration was higher among men than women (155 vs. 138 mug/L, P = 0.0000), and that of IGFBP3 lower (2.21 vs. 2.65 mg/L, P = 0.0000). Exclusion of subjects with demonstrable disorders did not significantly influence the distributions of serum-IGF-1 and serum-BP-3. Hb concentration was positively correlated to concentrations of IGF-1 (r = 0.15, P < 0.01 for the men; r = 0.34, P < 0.001 for the women), and IGFBP-3 (r = 0.07, n.s. for the men; r = 0.27, P < 0.001 for the women), and negatively correlated to EPO concentration (r = -0.34, P < 0.001 for the men; r = -0.42, P < 0.001 for the women). In multivariate analysis, serum concentrations of IGF-1, iron, and plasma concentrations of EPO were independently correlated to Hb among both men and women.
  
  
  CONCLUSIONS
  GH and/or IGF-1 are, independently from EPO and regardless of health status and sex, a significant determinant of Hb in elderly subjects.
authors.affiliation: Department of Medicine, the Sahlgrenska Academy at Göteborg University, Göteborg, Sweden. herman.nilsson-ehle@medic.gu.se
authors.forename: Herman
authors.initials: H
authors.lastname: Nilsson-Ehle
authors.forename: Bengt-Ake
authors.initials: BA
authors.lastname: Bengtsson
authors.forename: Göran
authors.initials: G
authors.lastname: Lindstedt
authors.forename: Dan
authors.initials: D
authors.lastname: Mellström
mesh_terms: D000368:Aged; D015415:Biomarkers / Q000097:blood; D004920:Erythropoiesis / Q000502:physiology*; D004921:Erythropoietin / Q000097:blood; D005260:Female; D013006:Growth Hormone / Q000097:blood; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D008297:Male; D011237:Predictive Value of Tests; D012737:Sex Factors
chemical_list: D015415:Biomarkers; D006454:Hemoglobins; D018972:Insulin-Like Growth Factor Binding Protein 3; D004921:Erythropoietin; D007334:Insulin-Like Growth Factor I; D013006:Growth Hormone