CLINICAL STUDY Impact of gender and androgen status on IGF-I levels in normal and GH-deficient adults

Objective: The regulation of IGF-I levels is complex and not only dependent on GH status, as the diagnostic sensitivity of serum IGF-I levels for GH deficiency (GHD) in adults is low. Other GH-related parameters have so far not proven to be of additional diagnostic value in GHD adults. In the present study we evaluated the impact of gender and androgen status on IGF-I levels and the diagnostic value of IGF-I and GH-related parameters in a population of adult hypopituitary patients and age- and gender-matched healthy subjects. Design: A cross-sectional study. Subjects: Fifty-nine GHD patients (40 males, mean age 39.3 6 1.7 (S.E.M.) years, and 19 females, mean age 41.9 6 2.6 years) and 69 healthy subjects (42 males, mean age 36.7 6 1.5 years, and 27 females, mean age 38.9 6 2.1 years). Results: IGF-I levels were low in the GHD patients (91 6 7 vs 173 6 7 mg/l, P < 0.001), and lower in female patients than in male (68 6 10 vs 100 6 8 mg/l, P 0.03). In the control group there was n