SHORT-TERM GROWTH AND COLLAGEN TURNOVER IN ASTHMATIC ADOLESCENTS TREATED WITH THE INHALED GLUCOCORTICOID BUDESONIDE

Short term lower leg growth, the insulin-like growth factor axis, and collagen turnover were assessed in 16 adolescents with asthma during t reatment with inhaled budesonide, 800 mu g/d, from a pressurized meter ed dose inhaler with a volume spacer. The design was a randomized doub le blind, placebo-controlled two-period crossover trial with treatment periods of 4 weeks and a 1-week wash-out. Lower leg growth was assess ed by knemometry. Serum levels of insulin-like growth factor-1, insuli n-like growth factor-binding protein-3 and the following markers of co llagen turnover were evaluated: Serum markers of type I collagen forma tion and degradation; the carboxy-terminal propeptide of type I procol lagen and the carboxy terminal pyridinoline cross-linked telopeptide o f type I procollagen (ICTP), the serum marker of type III collagen for mation; the amino-terminal propeptide of type III procollagen (PIIINP) and-the urinary concentrations of the type I collagen degradation pro ducts pyridinoline (PYD) and deoxypyridinoline (DPD) cross-links. Mean lower leg growth velocity was suppressed from 0.51 mn/week during pla cebo to 0.18 mm/week during budesonide treatment (p < 0.001). No stati stically significant effects on insulin-like growth factor-1, insulin- like growth faster-binding protein-3, or carboxy-terminal propeptide o f type I procollagen were observed. ICTP and PIIINP were reduced with 2.3 and 2.5 mu g/liter (p < 0.001 and p < 0.001, respectively) during budesonide treatment, urinary concentrations of PYD and DPD with 32.9 nmol/mmol creatinine (p < 0.005) and 6.8 nmol/mmol creatinine (p < 0.0 05), respectively. Significant correlations between lower leg growth v elocity and ICTP, PIIINP, PYD, and DPD during placebo (p < 0.01, p < 0 .05, p < 0.01, and p < 0.01) and budesonide (p < 0.05, p < 0.05, p < 0 .05, and p < 0.05) periods were found. Short term lower leg growth sup pression in adolescents treated with inhaled budesonide, 800 mu g/d, r eflects suppression of type I and III collagen turnover. (C) 1997 by E lsevier Science Inc.