Context: Survivors of childhood onset acute lymphoblastic leukemia (CO ALL) treated with prophylactic cranial radiotherapy (CRT) often exhibit GH deficiency (GHD), which is associated with increased prevalence of cardiovascular risk factors and cardiac dysfunction.

Objective: To evaluate the effect of GH replacement on cardiovascular risk factors and cardiac function in former CO ALL patients.

Design: 18 former CO ALL patients (age 19-32 yr) treated with CRT (18-24 Gy) and chemotherapy and with confirmed GHD were studied at baseline and after 12 (n = 18) and 24 months (n = 13) of GH treatment (median 0.5 mg/day). A group of 18 age- and sex-matched subjects served as controls.

Results: After 12 months of GH treatment a significant decrease in serum leptin (P = 0.002), leptin/kg fat mass (FM) (P = 0.01), plasma glucose (P = 0.004), FM (P = 0.002), hip (P = 0.04) and waist (P = 0.02) circumference, and increased muscle mass (P = 0.004) was recorded in the patients. Before GH treatment 6 patients had a metabolic syndrome, but after 12 months only one had it and after 24 months none. After 24 months of GH treatment an increase in left ventricular mass index (P = 0.06), and significant improvements in cardiac systolic function, measured as fractional shortening (P = 0.03) and ejection fraction (P = 0.03), were recorded.

Conclusions: Improvement in cardiac systolic function and reduced prevalence of metabolic syndrome was recorded after 2 yr of GH replacement in former CO ALL patients with GHD. Long-term follow up is highly warranted.