Adult height in short children born small for gestational age treated with growth hormone

Background and objective: Recombinant human growth hormone (rhGH) treatment in small for gestational age (SGA) children has been effective, although there is significant variability in the response. Adult height and the factors that determine the long-term response are evaluated.

Patients and design: A retrospective study of 80 patients born SGA with short stature treated with rhGH and followed until adult height (23 males).

Results: The group starting treatment pre-puberty reached a higher Adult height (-1.4±0.6 vs. -1.9±.6 in pubertal children), the highest final height gain was achieved in those treated for at least 2years prepuberty (1.32±.5 SDS). Factors associated with greater adult height gain were: a) less height, weight and BMI at start of treatment, b) lower chronological and bone age with lower IGF-I before treatment, c) greater distance to target height, d) higher growth velocity the first and second year of treatment, and higher height gain before and during puberty. The percentage of patients with good response in the first year ranged from 46.6% to 81.6% depending on the criteria. Growth velocity increase ≥3cm/ first year correlated best with long-term response.

Conclusion: rhGH treatment in children born SGA produced a varying increase in adult height that allowed them to reach their adult height. The best results occurred in the prepubertal group and did not depend on pituitary GH response.