CB03 Evaluation of trabecular bone score as a predictor of incident fragility fractures in patients with acromegaly: an international retrospective cohort study

Abstract

Acromegaly is associated with increased skeletal fragility that is not adequately reflected by bone mineral density. Trabecular bone score (TBS), an indirect measure of bone microarchitecture, has been associated with prevalent vertebral fractures in acromegaly, but its ability to predict incident fractures remains unclear. To evaluate the prognostic value of TBS for incident vertebral fractures in patients with acromegaly. This international retrospective cohort study included adult patients with acromegaly from eight European referral centres. Baseline was defined as the first assessment including both vertebral morphometry and TBS. The primary outcome was the occurrence of incident vertebral fractures during follow-up. A total of 184 patients were included, with a median follow-up of 4.2 years. Median disease duration at baseline was 7 years. Nineteen patients (10.3%) had prevalent vertebral fractures. Compared with patients without fractures, they were older (63.5 vs. 54.3 years; P = 0.02), had lower total hip T-scores (−1.04 vs. −0.27; P = 0.01), and lower TBS values (1.172 vs. 1.270; P = 0.01). The association between TBS and prevalent fractures remained significant after adjustment for age, sex, and hypocortisolism. During follow-up, incident vertebral fractures occurred in 17 patients (9.2%). TBS was not significantly associated with incident fractures (hazard ratio 0.85 per 0.1-unit increase; 95% confidence interval 0.60–1.21; P = 0.36). The strongest predictor of incident fractures was the number of prevalent vertebral fractures at baseline (hazard ratio 1.82 per additional fracture; 95% confidence interval 1.01–3.28; P = 0.04). In patients with acromegaly, TBS is associated with prevalent but not incident vertebral fractures. Periodic vertebral morphometric assessment remains essential for early fracture detection and fracture risk stratification.