Endocrine Abstracts

Hypopituitary patients on conventional hormone replacement, excluding GH have a reduced quality of life (QoL) and an increased risk of cardiovascular mortality. NICE guidelines on criteria for initiation and maintenance of therapy rely on QoL score defined by the Adult GHD assessment (AGHDA) questionnaire. However, it is uncertain how this score is related to other biological effects such as vascular risk.

Methods: Sixteen hypopituitary patients were recruited (peak GH <3 μg/l during ITT). Patients were randomised using a cross-over design to either six months of GH therapy or no treatment followed by six months of the other. At baseline, six and twelve months, the AGHDA questionnaire was completed, IGF-1, CRP, lipids, leptin and intercellular adhesion molecules (ICAM-1 and VCAM) were measured and waist circumference (WC), hyperinsulinaemic euglycaemic clamp, pulse wave velocity and 24 hour ambulatory blood pressure were carried out.

Results: GH had the expected effect on IGF-1 with a significant increase from 67.7±7.2 to 166.7±16.2 μg/l (P<0.001). AGHDA fell from 10.4 to 6.4 (P=0.059), waist circumference reduced from 88.1 to 84.7 cm (P=0.09), CRP reduced significantly from 3.78 to 1.99 mg/l (P=0.007), 24 hour mean arterial BP fell from 91.3 to 89.3 mmHg (P=0.006) and PWV reduced from 8.1 to 6.7 m/s (P<0.05). Insulin sensitivity did not alter after GH therapy. There was a strong trend to correlation between improvement in QoL and increase in IGF-1 (r=0.49, P=0.09) but there was no correlation between improvement in QoL and reduction in waist circumference, BP, PWV, CRP, total cholesterol, leptin or intercellular adhesion molecules (ICAM-1, VCAM).

Conclusion: Growth hormone replacement induces improvements in QoL and discernible reductions in surrogates of cardiovascular risk. Lack of correlation between QoL and cardiovascular risk may mean patients are given or denied GH therapy inappropriately.