Objectives: To evaluate the effects of growth hormone deficiency (GHD) and of growth hormone (GH) therapy on cardiac structure in adults with childhood-onset GHD.
Setting: Out-patient clinic in the Italian Institute for Auxology, Milan.
Subjects: Eight adults with childhood-onset GHD and eight healthy controls, matched for sex, age, exercise and body mass index.
Interventions: Recombinant GH (Saizen Serono, Italy), administered in a conventional dose of 0.5 IU kg-1 week-1 for 6 months.
Main outcome measures: Cardiac structure parameters, evaluated by two-dimensional, M-mode and Doppler echocardiograms, and stress test, by means of a modified Bruce protocol with a bicycle ergometer, were determined before and after 6 months GH therapy.
Results: Before treatment, mean (+/- SE) intraventricular septal thickness (IVST: 7.1 +/- 0.2 mm), LV posterior wall thickness (LVPT: 5.2 +/- 0.1 mm), LV mass (LVM: 94.6 +/- 5.0 g), LV mass index (LVM/body surface area, LVMI: 65.1 +/- 3.0 g m-2) and left ventricular end-diastolic diameter (LVED: 41.4 +/- 0.6 mm) of patients were significantly lower (P < 0.01) than in controls, whilst LV end-systolic diameter (LVES) of patients (25.5 +/- 0.7 mm) was similar to controls (27.5 +/- 0.7). GH treatment significantly (P < 0.01) increased LVPT (6.8 +/- 0.2 mm), LVM (111.6 +/- 4.6 g) and LVMI (80.5 +/- 3.5 g m-2); no significant changes were observed in LVED, LVES and IVST values. The stress test showed a significant improvement of cardiac performance, as demonstrated by the reduction of blood pressure x heart rate product at the same workload (basal: 32,722.5 +/- 897.4 vs. after: 25,574.6 +/- 439.7).
Conclusions: GH plays a role in the maintenance of a normal cardiac structure in adulthood. The present study suggests that GH treatment might be able to improve the cardiac structure of patients with childhood-onset GHD.