Response to growth hormone therapy in Indian patients

Abstract

To analyse response to growth hormone therapy on Indian patients with short stature. Data were collected on 71 patients of short stature on GHT. All patients underwent clinical and hormonal evaluation. GHD was diagnosed in the presence of short stature (height SDS < 2) and peak GH levels < 10 ng/ml. Bone age was estimated using Tanner Whitehouse 3 method (TW3). Primary GHD (73%) was the commonest diagnosis among patients on GHT, followed by organic GHD (12.6%), genetic syndromes (8.4%) and systemic diseases (5.4%). Mean chronological age at presentation was 10.07+/-3.26 years (median-11 years, range 3-15 years), mean height age was 6.98+/-2.82 years (median 7.5 years, range 1-13 years) and mean bone age (available for 55 patients) was 7.19+/-3.1 years (median 8.2 years, range 1.3-13 years). Patients with systemic diseases (6.75+/-3.5 years) presented earlier, compared to patients with GHD (10.27+/-3.16 years) and genetic syndromes (10.18+/-3.20 years) (p=0.349). Most of the patients on GHT were in the age group 9-15 years (60.6%). Mean height gain with GHT was 8.7+/-2.7 cm (median 8.3 cm, range 3.0-13 cm) during 1st year then decreased to 6.9+/-2.4 cm (median 7.0 cm, range 3.0-12.5 cm) in the second year, and was maintained through the third year (mean 7.1+/-3.0 cm, median 7.0, range 3.0-13 cm). Among patients with GHD, those with primary deficiency had significantly better response to GHT in 1st year than secondary deficiency (9.0+/-2.65 vs 6.8+/-3.03 cm, p = 0.026). Response to GHT was negatively correlated with CA (r-0.27, p = 0.05), HA (r-0.47, p = 0.027) and BA (r-0.31, p=0.022) at presentation. Four patients (5.6%) developed hypothyroidism and one patient each developed disseminated tuberculosis and rickets. One patient of Turner's syndrome died of adrenal carcinoma. Short follow up and absence of measurement of IGF-1 and IGFBP3 were major limitations of this study. Response to GHT in Indian patients is comparable to western counterparts. Maximum height gain on GHT is during the first year than decreases in second year, but is maintained through third year. Patients with primary GHD had better response than secondary GHD. Response to GHT is negatively correlated with chronological, height and bone age at presentation.