Should short children who are not deficient in growth hormone be treated?

Abstract

There are many causes of short stature during childhood and adolescence.1 About half of all children referred to pediatric endocrinologists for an evaluation of their growth show normal variants of short stature. This means that their height falls below the conventional cutoff of 2 standard deviations below the mean but they have healthy increments in growth that parallel the growth channels on standard growth charts for the general population.1,2 A deficiency in growth hormone is the main endocrinologic cause of pathologically short stature. A major objective of treatment with growth hormone in children (who typically are prepubertal at the start of treatment) is to accelerate the speed of growth to reduce discrepancies in height with peers during childhood and adolescence and to enable them to reach an adult height that is commensurate with their genetic potential.3 Because the sole source of growth hormone before 1985 was pituitary glands taken from cadavers, there was never enough growth hormone available to meet the needs of children who had a deficiency. The treatment was, therefore, restricted to those with the most severe deficiencies. The hormone became more widely available after biosynthetic growth hormone was manufactured in 1985. The availability of biosynthetic growth hormone ensures that children who are deficient can have replacement therapy, but it also has created the opportunity to treat children who are short but do not have a deficiency. As time passes, some of these newer, nontraditional applications are becoming accepted as the standard of care in the United States.4 The treatment of short children who are not deficient in growth hormone is predicated on the widespread belief that being taller improves children's psychological well being.5 Moreover, it is thought that increased height will reduce or eliminate their risk status for the development of problems as adults. The broader use of this comparatively intensive, chronic, and costly hormonal intervention is supported by complaints made by short youths of psychosocial stresses related to their height and society's beliefs about the disadvantages of being short.6 In the United States, growth hormone is more frequently prescribed to youths who are not deficient in growth hormone than to those who are.4 This aspect of clinical practice remains controversial.4, 7 Practice guidelines on the use of growth hormone in children who are short clearly state that decisions regarding “instituting or continuing therapy should be individualized... and be guided by the goal of improving the quality of life of the child and future adult.”8 Unfortunately, these recommendations, designed for pediatric endocrinologists, provide no guidance in how to conduct an evaluation of the quality of the child's life. Reviewing the assumptions that are frequently made about the quality of life of short children who are not deficient in growth hormone may help clinicians in making decisions on managing these children.