Objective. We evaluated metabolic and cardiac parameter changes with GH-therapy. Design. Sixteen adults with childhood-onset hypopituitarism receiving pituitary hormone replacement, except GH-replacement, were assessed at baseline and after 6 and 12 months of GH-replacement. Sixteen healthy adults matched for sex, age, weight, height, body mass index, and body surface area served as the control group to compare cardiac function in both groups. Results. All patients had GH-deficiency. After 12 months, serum insulin-like growth factor-1 levels normalized. Basal glucose or insulin levels had no alterations. The low/high density lipoprotein-cholesterol ratio decreased (3.18 +/- 1.32 x 2.17 +/- 0.8, p < 0.001). Percent lean body mass increased (69.9 +/- 5.5 x 78.4 +/- 8.1%). and percent fat body mass decreased (30.1 +/- 5.5 x 21.6 +/- 8.1%) (both, p < 0.001). Before treatment, patients had decreased left ventricular (LV) echocardiographic morphologic indexes, which were corrected (initial versus 12 months): interventricular septal thickness (0.68 +/- 0.06 x 0.78 +/- 0.06 cm), LV posterior wall thickness (0.69 +/- 0.07 x 0.78 +/- 0.05 cm), and LV mass index (58.9 +/- 11.0 x 71.1 +/- 9.4g/m(2)) (all, p < 0.001). Exercise capacity improved, as assessed by oxygen consumption (7.84 +/- 1.44 x 9.67 +/- 1.74 METS, p < 0.001). Conclusions. GH-replacement seems to reduce cardiovascular risks in adults with childhood-onset GH-deficiency. (C) 2003 Elsevier Science Ltd. All rights reserved.