Predicting and Monitoring of Growth in Children with Short Stature during the First Year of Growth Hormone Treatment

ABSTRACT. Fifteen prepubertal short stature children (10 girls, 5 boys), mean age 9.6 years (range 5.2–12.7 years), with normal response to growth hormone stimulation tests (group A) or partial growth hormone deficiency (GHD) of idiopathic nature (group B) were included in a controlled longitudinal study for evaluation of predictive parameters for the long-term growth response after administration of biosynthetic human growth hormone (B-hGH). The average knee–heel length velocity for the first 3 months was significantly correlated to total body height velocity during the following 9 months ( p <0.0008). By contrast, this association could not be found for height velocity during the same period. The increase in serum values of alkaline phosphatase and insulin-like growth factor I (IGF-1) during the first month of treatment was not significantly correlated to height velocity during the first year. During one year of treatment with B-hGH the mean height velocity for groups A and B increased from 4.4 cm/year (range 2.5–6.5) to 7.6 cm/year (range 4.7–10.6). Bone age advanced by 1.08 t0.60 per chronological year. The ratio between total height and knee-heel length prior to treatment was 3.34 ± 0.10 and after one year 3.33 ± 0.10, suggesting a proportional linear growth. An inverse relationship was observed between the ratio and chronological age. In conclusion, early knee–heel measurement may be a useful non-invasive predictor of long-term linear growth in children during treatment with growth hormone, and the ratio of total height to lower leg length may be of importance in detecting dysproportional growth.