Growth, growth hormone and cognitive functions

Abstract

The interactions among short stature, growth hormone (GH) and cognitive functions have been extensively studied so far. However, although it seems well established that short stature is associated with cognitive problems, little effort has been made to point out the presence of specific psychological effects related to the different forms of short stature. In 'short normal' children, the presence of a scholastic underachievement seems to suggest that short stature 'itself' might predispose these patients to some of their psychosocial difficulties. The higher incidence of academic failure, in presence of a normal intellectual functioning, has been attributed to environmental and psychosocial factors, including over-protective parents and low self-esteem resulting from the impact of short stature. These problems appear to be common also to other forms of short stature (such as Turner's syndrome) where, however, they are frequently associated with other specific deficits. The in vivo model which might allow, at least in part, better understanding of GH (per se)-dependent effects is represented by GH deficiency (GHD), in which, however, the specific role of GH on psychological functioning is frequently masked by the presence of associated hormonal deficiencies. Children with isolated GHD are reported to have specific educational deficits, in particular learning disability and attention-deficit disorders, which have been tentatively attributed to a compromised intellectual potential. The psychological effects of long-term GH treatment in children with GHD still remain controversial, with some retrospective studies describing a generally beneficial outcome. Since early experiences in school are closely related to success in adult life, the possible implications that GHD during childhood holds during adulthood have been recently considered. Although regional differences have been observed in subgroups of adults with GHD, it seems that these patients have normal cognitive functions and educational attainment, but are more likely to be unemployed (and unmarried) than members of the general population. In general, patients with GHD, who have been treated at centers where psychological counselling was an integral part of the treatment program, seem to be better adjusted in adult life. For these reasons, a multidisciplinary treatment approach could allow early detection of problems in academic achievement and psychosocial development in patients with short stature, being immediately able to provide the appropriate educational and counselling interventions.