title: Secondary IGF-I deficiency as a prognostic factor of growth hormone (GH) therapy effectiveness in children with isolated, non-acquired GH deficiency.
abstract: OBJECTIVE
  Growth hormone (GH) deficiency (GHD) has recently been classified as secondary IGF-I deficiency but the significance of IGF-I measurement in diagnosing GHD is still discussed. The aim of the study was to assess the relationships between IGF-I secretion and GH therapy effectiveness in children with GHD.
  
  
  METHODS
  The analysis comprised 300 children with isolated, non-acquired GHD (GH peak below 10 μg/l) who completed GH therapy and attained final height (FH). In all patients IGF-I concentration was measured before the treatment and IGF-I deficiency was diagnosed if IGF-I SDS for age and sex was below -1.0. The following auxological indices were assessed: patients' height SDS before treatment (H₀SDS), FH SDS and improvement of FHSDS vs. H₀SDS (ΔHSDS).
  
  
  RESULTS
  In the patients with IGF-I deficiency when compared with those with normal IGF-I secretion before treatment, significantly better FH SDS (-1.42±0.90 vs. -1.74±0.86, p=0.004) and ΔHSDS (1.64±1.01 vs. 1.32±1.05, p=0.010) were observed, despite similar H₀SDS (- 3.07±0.78 vs. - 3.11±0.77, p=0.63) and GH peak (7.0±3.1 μg/l vs. 6.8±2.1 μg/l, p=0.55). The patients who achieved FH over 10(th) centile had significantly lower IGF-I SDS before treatment than those with FH below 10(th) centile (- 1.59±1.54 vs. - 1.20±1.64, p=0.04), despite similar GH peak (7.0±2.3 μg/l vs. 6.7±3.1 μg/l, p=0.45). The patients with ΔHSDS over the median value had significantly lower IGF-I SDS than those with ΔHSDS below the median value (- 1.59±1.71 vs. - 1.09±1.47, p<0.0001), despite similar GH peak (6.8±2.5 μg/l vs. 7.0±2.7 μg/l, p=0.86).
  
  
  CONCLUSIONS
  In children with isolated, non-acquired GHD, secondary IGF-I deficiency is an important predictor of better GH therapy effectiveness.
authors.affiliation: Department of Endocrinology and Metabolic Diseases, Polish Mother's Memorial Hospital - Research Institute, Lodz, Poland.
authors.forename: J
authors.initials: J
authors.lastname: Smyczyńska
authors.affiliation: Department of Endocrinology and Metabolic Diseases, Polish Mother's Memorial Hospital - Research Institute, Lodz, Poland.
authors.forename: R
authors.initials: R
authors.lastname: Stawerska
authors.affiliation: Department of Endocrinology and Metabolic Diseases, Polish Mother's Memorial Hospital - Research Institute, Lodz, Poland.
authors.forename: M
authors.initials: M
authors.lastname: Hilczer
authors.affiliation: Department of Endocrinology and Metabolic Diseases, Polish Mother's Memorial Hospital - Research Institute, Lodz, Poland.
authors.forename: A
authors.initials: A
authors.lastname: Lewiński
mesh_terms: D000293:Adolescent; D001827:Body Height / Q000187:drug effects*; D002648:Child; D004393:Dwarfism, Pituitary / Q000097:blood / Q000188:drug therapy*; D005260:Female; D020249:Hormone Replacement Therapy; D019382:Human Growth Hormone / Q000097:blood / Q000494:pharmacology / Q000627:therapeutic use*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000172:deficiency* / Q000378:metabolism; D008297:Male; D011379:Prognosis; D016896:Treatment Outcome
chemical_list: D019382:Human Growth Hormone; D007334:Insulin-Like Growth Factor I