Effects of growth hormone and nutritional therapy in boys with constitutional growth delay: A randomized controlled trial

Objective: To examine whether supplemental nutrition augments the anabolic actions of growth hormone (GH) in boys with constitutional delay of growth and maturation (CDGM). Study design: We conducted a randomized, controlled trial at an outpatient clinical research center. Subjects were 20 prepubertal boys (age, 9.3 ± 1.3 years) with CDGM (height standard deviation score, -2.0 ± 0.5; bone age delay, 1.8 ± 0.8 years; body mass index standard deviation score, -1.2 ± 1.0; peak stimulated GH, 15.7 ± 7.7 ng/mL), who were randomized (n = 10/group) to 6 months observation or daily nutritional supplementation, followed by additional daily GH therapy in all for another 12 months. t tests and repeated measures analyses of variance compared energy intake, total energy expenditure (TEE), growth, hormones, and nutrition markers. Results: Energy intake was increased at 6 months within the nutrition group (P = .04), but not the observation group, and TEE was not statistically different within either group at 6 months. Addition of 6 months GH resulted in higher energy intake and TEE in the GH/nutrition group at 12 months (P < .01), but not in the GH group versus baseline. Height, weight, lean body mass, hormones, and nutrition markers increased comparably in both groups throughout 18 months. Conclusion: Boys with CDGM use energy at an accelerated rate, an imbalance not overcome with added nutrition. GH therapy increases growth comparably with or without added nutrition in these patients.