Insulin resistance is an intrinsic defect independent of fat mass in women with Turner's syndrome

Horm Res. 2006;65(2):69-75. doi: 10.1159/000090907. Epub 2006 Jan 10.


Background/aims: Turner's syndrome (TS) is associated with increased insulin resistance and adiposity, which might be associated with type 2 diabetes in later life. We aimed to determine whether the defect in insulin sensitivity is a primary intrinsic defect in TS or dependent on variation in body composition.

Methods: Sixteen women with TS not on growth hormone replacement but receiving oestrogen replacement therapy [age (mean +/- SD): 30.2 +/- 8.5 years; height-corrected fat-free mass: 26.1 +/- 3.1 kg/height] and a control group of 16 normal healthy women (age: 30.1 +/- 8.2 years; height-corrected fat-free mass: 25.9 +/- 2.4 kg/height) were studied. Fasting blood samples were obtained for measurement of glucose, insulin, IGF-I, IGFBP-1, IGFBP-3 and lipid levels. The hyperinsulinaemic euglycaemic clamp was performed to assess peripheral insulin sensitivity (M value), and the Homeostasis Model Assessment (HOMA-S) was used to estimate fasting insulin sensitivity. Body composition was assessed using a dual-energy X-ray absorptiometry scan.

Results: Fasting insulin sensitivity (HOMA-S 103.2 +/- 78.6 vs. 193.9 +/- 93.5, p = 0.006) was lower in TS subjects compared to controls as was whole-body insulin sensitivity (M value 2.9 +/- 1.9 vs. 5.5 +/- 2.6 mg/kg/min, p = 0.003). In a multiple regression analysis the Turner karyotype was significantly related to insulin sensitivity (p = 0.008) independent of any differences in fat-free mass and percent whole-body fat mass.

Conclusion: The increased insulin resistance in women with TS is independent of measures of body composition and may represent an intrinsic defect related to their chromosomal abnormality.

MeSH terms

  • Adolescent
  • Adult
  • Body Composition / physiology*
  • Case-Control Studies
  • Cholesterol / blood
  • Estrogens / therapeutic use
  • Fasting / blood
  • Female
  • Glucose Clamp Technique
  • Humans
  • Insulin Resistance / physiology*
  • Middle Aged
  • Regression Analysis
  • Turner Syndrome / drug therapy
  • Turner Syndrome / physiopathology*


  • Estrogens
  • Cholesterol