Spine Bone Texture Assessed by Trabecular Bone Score in Active and Controlled Acromegaly: A Prospective Study

Context: Acromegalic patients have an increased vertebral fracture (VFx) risk due to bone quality reduction, independently of bone mineral density (BMD).Objective: The aim of the study is to describe bone quality in acromegaly, measured by trabecular bone score (TBS), a noninvasive index for assessing bone microarchitecture.Methods: We collected data from 18 patients (13 female, age 56.2 +/- 15 years) newly diagnosed with acromegaly. Thirty-six age- and sex-matched healthy controls were also recruited. Pituitary function, bone and calcium-phosphorous metabolism, and BMD at spine and femur and TBS (by dual-energy x-ray absorptiometry) were assessed in acromegalic patients at diagnosis and 12 months after the achievement of insulin-like growth factor 1 (IGF-1) normalization.Results: At diagnosis, BMD and the VFx prevalence were comparable between patients and controls (28.3 +/- 5.9 vs 27.6 +/- 3.7 and 11% vs 8.3%), whereas TBS was significantly lower in acromegalic patients (1.20 +/- 0.13 vs 1.30 +/- 0.06; P< .001) and carboxytermi nal telopeptide (CTX) and osteocalcin were significantly higher compared to controls (707 +/- 365.7 vs 371 +/- 104.1 pg/mL; P= .001 and 31.6 +/- 15.4 vs 17.0 +/- 5.7 ng/ mL; P= .001, respectively). One year after IGF-1 normalization, a significant reduction of bone turnover indexes was observed in the group of acromegalic patients surgically cured (osteocalcin decrease of 61.2%, CTX decrease of 60.3%) compared to the ones controlled by medical therapy (osteocalcin decrease of 39%, CTX decrease of 40.7%; P= .01 and P = .001, respectively). Despite these findings, noTBS or BMD variations were observed.Conclusion: Acromegalic patients have impaired bone quality despite normal density. Achieving normal growth hormone secretion rapidly leads to the normalization of bone turnover.