Beyond height: Effects of growth hormone on body composition and physical function in children

Physiologic effects of growth hormone (GH) extend beyond the stimulation of linear growth during childhood and adolescence. Children and adults with G H deficiency (GHD) also demonstrate significant reductions in lean body mas s, increases in percentage of body fat, and subnormal bone mineral density. In particular, excessive fat tissue is distributed in visceral and truncal areas, locations associated with increased cardiovascular risk. Replacemen t of GH attenuates these abnormalities. Children with body composition abno rmalities resembling the GHD state (e.g., Prader Willi syndrome) also respo nd favorably to administration of GH treatment with decreases in adipose ti ssue, and increases in lean body (muscle) mass, fat utilization and oxidati on, and energy expenditure. Importantly, improvements in strength and agili ty are also observed in these disabled children. Effects of GH on body comp osition, aside from well-known benefits on growth, appear to be important d uring childhood.