Long-term Response to Recombinant Human Growth Hormone Therapy in Indian Children with Growth Hormone Deficiency

Growth hormone deficiency (GHD) remains the most common indication for use of recombinant human growth hormone (rhGH) therapy in clinical practice. However, there is a paucity of studies focusing on long-term response to rhGH therapy in the Indian context.

To determine the response to rhGH therapy and its predictors in children with GHD followed up at a tertiary care center in North India.

We performed a retrospective review of the records of children with GHD who received rhGH therapy for at least 1 year. The relevant anthropometric, biochemical and radiological data at baseline and follow-up were recorded.

A total of 99 children (64 boys, 35 girls; 61 isolated GHD, 38 multiple pituitary hormone deficiency) were studied. The mean (±SD) age and height SDS at treatment initiation were 12.4 (±3.0) years and -4.0 (±1.1) respectively, while median (IQR) serum insulin-like growth factor 1 (IGF-1) and peak growth hormone level on clonidine stimulation were 73 (25-167) ng/ml and 1.1 (0.4-3.6) ng/ml respectively. The height velocity was highest during the first year of treatment (10.6 ± 3.0 cm/year), declining to 8.7 ± 2.7 and 7.9 ± 2.2 cm/year during second and third year, respectively. Over the subsequent years, there was further graded fall in height velocity, declining to 4.8 ± 3.6 cm/year (n = 2) during the seventh year. The height gain during first year was negatively correlated with age at initiation of treatment, baseline height SDS, baseline serum IGF-1 and peak serum GH level on GH stimulation test, while it showed a positive correlation with bone age delay at baseline. Only baseline height SDS was found to have a significant negative correlation with height gain during the second year.

This study provides data on long-term response to rhGH therapy and its predictors in Indian children with GHD.