Growth hormone treatment before the age of 4 years prevents short stature in young girls with Turner syndrome

Abstract

Adult height deficit seen in Turner syndrome (TS) originates, in part, from growth retardation in utero and throughout the first 3 years of life. Earlier diagnosis enables earlier therapeutic intervention, such as with recombinant human GH (r-hGH), which may help to prevent growth retardation. In this open-label, multicentre phase III study, we investigated efficacy and safety in r-hGH treatment in young girls with TS. Girls (n=61) aged <4 years with TS receiving 0.035-0.05 mg/kg per day r-hGH for 4 years were compared with an historical control group (n=51) comprising untreated, age- and height-matched girls with TS. The main outcome measure was change in height SDS (H-SDS). Other measures included changes in height velocity SDS, IGF1 levels and glucose metabolism. After 4 years, a gain in mean H-SDS of 1.0 SDS (from -2.33±0.73 to -1.35±0.86 SDS) was observed with r-hGH treatment, in contrast to the decrease in mean H-SDS of 0.3 SDS in the control group (from -2.09±0.81 to -2.44±0.73 SDS; P<0.0001). r-hGH treatment was the main predictor of H-SDS gain and accounted for 52% of variability (multivariate analysis). r-hGH was well tolerated. As expected, IGF1 levels rose with treatment. A case of transient glucose intolerance resolved after dietary adaptation. Early treatment with r-hGH helps to prevent natural evolution towards short stature in most girls with TS. IGF1 levels and glucose metabolism should be monitored routinely during r-hGH therapy.