EFFECT OF LOW-DOSAGE RECOMBINANT HUMAN GROWTH-HORMONE THERAPY ON PULMONARY-FUNCTION IN HYPOPITUITARY PATIENTS WITH ADULT-ONSET GROWTH-HORMONE DEFICIENCY

An impairment of the pulmonary function has been described in adult pa tients with childhood-onset growth hormone deficiency (GHD). We examin ed forced vital capacity (FVC), forced expiratory volume (FEV1), total lung capacity (TLC), functional residual capacity (FRC), residual vol ume (VR) and the index of inspiratory strength, middle tidal volume an d tidal inspiratory time ratio (TV/I), in 29 patients with adult-onset GHD. Data were compared with those obtained in 46 healthy control sub jects. Only the FEV1/FVC ratio was statistically different (p=0.04) be tween the two groups of subjects. In a group of 15 GHD patients low do sages (0.5-1 IU/day sc, bedtime) of recombinant human GH (rh-GH; n.=8 subjects) or placebo (n.=7) were given at random for a 6-month period. A significant increase in IGF-I levels was noted in the rh-GH-treated group (p=0.04) but not in the placebo group. After the 6-month period no statistically significant changes in pulmonary function were found between the rh-GH-treated and placebo-treated GHD patients. This stud y shows that adult-onset GHD patients suffer from minimal impairment o f pulmonary function. Low rh-GH dosages able to induce an increase in IGF-1 levels do not improve pulmunary function. The effect of rh-GH on respiratory muscle strength could be related to the age at which GHD diagnosis is made, or induced only by high rh-GH dosages given for a l ong time. (J. Endocrinol. Invest. 21: 423-427, 1998) (C)1998, Editrice Kurtis