Endocrine Abstracts (2017) 49 OC12.5 | DOI: 10.1530/endoabs.49.OC12.5

Effects of pegvisomant and somatostatin receptor ligands on risk of vertebral fractures in patients with Acromegaly

Sabrina Chiloiro1, Gherardo Mazziotti3, Antonella Giampietro1, Anna Maria Formenti2, Antonio Bianchi1, Marilda Mormando1, Alfredo Pontecorvi1, Andrea Giustina4 & Laura De Marinis1

1Pituitary Unit, Catholic University of the Sacred Heart, Rome, Italy; 2Department of Molecular and Translational Medicine, University of Brescia, Brescia, Italy; 3Department of Internal Medicine, Mantua Hospital, Mantua, Italy; 4Chair of Endocrinology, Vita-Salute San Raffaele University, Milan, Italy.

Acromegalic osteopathy is an emerging complication of chronic GH excess characterized by increase in bone turnover, deterioration in bone microarchitecture and high risk of vertebral fractures (VFs). Medical therapies may exert direct effects on peripheral targets leading to improvement of clinical outcomes regardless of biochemical control of acromegaly. In this longitudinal study, we compared the effects pegvisomant (PegV) and somatostatin receptor ligands (SRLs) on VF risk in 80 acromegaly patients (47 females, 33 males; mean age 53 years, range 24–86 years) who were prospectively evaluated by quantitative vertebral x-ray morphometric approach. During the 30 month study period, 39 patients (48.8%) were treated with PegV, 33 (41.2%) with SRLs and 8 (10%) showed a controlled disease after neurosurgery. At follow-up, 23 patients (28.8%) experienced incident VFs which were significantly correlated with persistently active disease (OR .49, C.I.95% 1.75–17.22; P=0.003) and preexisting VFs (OR 2.79, C.I. 95%1.03–7.61; P=004). By contrast, no significant differences in incident VFs were found between patients receiving PegV and those treated with SRLs alone, either when disease was persistently active (58.3% vs 60.0; P=0.94) or when disease was controlled by treatment (20.0 vs 27.0%; P=0.67). In conclusion, this longitudinal study showed that PegV and SRLs had comparable effects on VF risk in acromegaly. Biochemical control as well as early diagnosis of the disease are the main endpoints for fracture prevention in acromegaly.