Recombinant Human GH Replacement Therapy and Thyroid Function in a Large Group of Adult GH-Deficient Patients: When Does<scp>l</scp>-T₄Therapy Become Mandatory?

Abstract

The effect on thyroid function of GH administration to 66 adult patients with severe GH deficiency was studied. Seventeen patients were euthyroid, and 49 had central hypothyroidism and were adequately treated with l-T4. Forty patients were assigned to a low recombinant human GH (rhGH) regimen (3 μg/kg body wt·d for 3 months followed by 6 μg/kg body wt·d for another 3 months) and 26 to a higher one (6 μg/kg body wt·d for 3 months followed by 12 μg/kg body wt·d for another 3 months). Serum IGF-I, TSH, free T4 (FT4), free T3 (FT3), reverse T3, T4-binding globulin, and antithyroid autoantibody (TgAb and TPOAb) were measured in basal condition and after 3 and 6 months of therapy.