Objective : Data on trabecular bone mass in acromegaly are controversial. All the studies are cross-sectional and bone mineral density (BMD) has been evaluated largely by dual X-ray absorptiometry (DXA), which is influenced by bone enlargement. In this study we assessed in acromegalic patients the effects overtime of GH excess on trabecular bone mass measured by single-energy quantitative computed tomography (QCT) which is not influenced by bone size. Design : Longitudinal retrospective study. Patients : A total of 46 acromegalic patients followed-up for 48 months (median), subdivided into four groups: group A (eugonadal patients with active disease: n = 13), group B (hypogonadal patients with active disease; n = 9), group C (eugonadal patients with controlled disease; n = 10), group D (hypogonadal patients with controlled disease; n = 14). Measurements : Serum GH and IGF-I levels, spinal trabecular BMD, and vertebral fractures were evaluated in all patients. BMD variations were reported as change (Δ) in Z-values (Z-QCT) measured at baseline and end of follow-up per year (Δ Z-QCT). Results : Δ Z-QCT was greater in group A vs. group B and D (P = 0·002 and P = 0·0001, respectively) and in group C vs. group D (P = 0·009). Multivariate regression analysis showed that hypogonadal status (β = -0·69; P = 0·001) and baseline duration of hypogonadism (β = 0·44; P = 0·02) but not baseline duration of acromegaly, length of follow-up and disease activity, were significantly associated with Δ Z-QCT. Conclusions : This longitudinal study suggests that the effect of chronic GH excess on spinal trabecular bone mass seems to be anabolic in active eugonadal patients but not in hypogonadal ones.
ASJC Scopus subject areas
- Endocrinology, Diabetes and Metabolism