Changes of amino-terminal propeptide of C-type natriuretic peptide and growth velocity in patients with idiopathic short stature or isolated growth hormone deficiency after recombinant human growth hormone treatment

Abstract

Objective To explore the value of amino-terminal propeptide of C-type natriuretic peptide (NTproCNP) in evaluating the efficacy of therapy with recombinant human growth hormone ( rhGH ) in patients with idiopathic short stature (ISS) and isolated growth hormone deficiency ( IGHD ).Methods Forty-eight prepubertal children( IGHD n=25,ISS n=23 ) treated for at least 1 year with rhGH were included.Serum insulin-like growth factor- Ⅰ ( IGF- Ⅰ ) and NTproCNP levels were measured before starting treatment and 6 months later.Twelve months after starting treatment,all patients were assessed and annual growth velocity ( GV ),height standard deviation score ( HTSDS),and gained HTSDS (△HTSDS) were recorded.Results In GHD group,positive relationships between GV and change of IGF- ISDS( △IGF- ISDS ),GV and change of NTproCNP concentrations(△NTproCNP) were found( r=0.407,P=0.044 ;r=0.490,P=0.013 ).GH peak value was also positively associated with IGF- ISDS and NTproCNP before therapy ( r =0.558,P =0.004; r =0.630,P =0.001 ).△IGF- ISDS and △NTproCNP were positively associated after therapy ( r =0.466,P =0.019 ).In ISS group,GV was associated with △NTproCNP ( r=0.845,P＜ 0.01 ).Conclusions NTproCNP is a novel biomarker of growth as its level increases during growth-promoting treatment.Furthermore,IGF- Ⅰ is also valuable in evaluating the efficacy of rhGH therapy in short stature patients. Key words: Growth hormone treatment; Growth hormone deficiency; Idiopathic short stature; Insulinlike growth factor- Ⅰ ; C-type natriuretic peptide