ABSTRACT
STUDY OBJECTIVES: It is well known that systemic administration of corticosteroids has a dual effect on growth hormone (GH) secretion in man: acute systemic administration stimulates GH release, whereas chronic administration consistently blocks it. In this study, we evaluate whether administration of inhaled corticosteroids could acutely stimulate GH secretion, and whether this effect could be dose related. DESIGN: Double-blind, placebo-controlled, crossover study. PARTICIPANTS: Eight normal male volunteers all recruited at our institution. INTERVENTIONS: Administration of increasing doses of inhaled beclomethasone dipropionate (BDP; range, 50 to 1,500 mug) or placebo. MEASUREMENTS AND RESULTS: Blood samples for GH determinations were collected at - 15, 0, 60, 120, 180, 240, 300, and 360 min in relation to BDP or placebo administration. The results of this study show a peak GH secretion at 240 min after the administration of BDP at doses > 100 microg. The comparisons among the peaks obtained with increasing doses showed a dose-response effect on GH secretion, starting from 100 to 1,000 microg. BDP 1,500 microg did not induce a peak significantly different from that obtained with 1,000 microg. When we calculated the GH response to BDP as an area under the curve (micrograms per liter x 6 h), the data confirmed that GH secretion was elicited in a dose-related manner. CONCLUSIONS: Our data show that inhaled BDP at dose > 100 microg acutely stimulates GH secretion in a strictly dose-dependent manner. We propose this test as a surrogate for systemic absorption and as a valuable test to compare systemic effects among different inhaled steroids.
