ECE2019 Poster Presentations Calcium and Bone 1 (60 abstracts)
1Comenius University Faculty of Medicine, 5th department of Internal Medicine, University Hospital, Bratislava, Slovakia; 2National institute of Endocrinology and Diabetology, Lubochna, Slovakia; 3Comenius University Jessenius Faculty of Medicine, 1th department of Internal Medicine, University Hospital Martin, Martin, Slovakia; 4Department of Medicine, University of Wisconsin, Madison, USA; 5Galgo Medical, Barcelona, Spain; 6University of California San Francisco, San Francisco, USA.
Introduction: Patients suffering from acromegaly, despite normal or even higher bone mineral density (BMD), have prevalent vertebral fractures (VFs). Impaired bone microarchitecture is involved fragility fracture development, but vitamin D status could be involved in this impairment.
Aim of the study: Comparison of bone parameters such as BMD, trabecular bone score (TBS) and 3D-SHAPER parameters in acromegaly patients according to level of 25(OH)D3.
Methods: A cross-sectional study recruited all acromegaly patients who came for visit from 6/2016 8/2017. In all subjects a single measurements of pituitary axis hormone levels, bone turnover markers (BTMs), BMD, (total hip [TH] and lumbar spine [LS]), TBS and 3D-SHAPER [volumetric BMD (vBMD), surface BMD (sBMD) and mean cortical thickness (mCth)] were performed. Levels of 25(OH)D3 were measured by measured in a chromatographic assay using a simple isocratic HPLC system with UV detection (Chromsystem®) (interassay variability CV, 0.8−3%). All patients were advised to use 800 IU of cholecalciferol and 1000 mg of Ca supplement daily.
Results: 106 patients with acromegaly (mean age 56.6 years, BMI 30.2 kg/m2) were included. Patients in lowest quartile (Q1vitD; mean 111.1 nnmol/) of 25(OH)D levels had lower LS BMD (0.99 vs. 1.06 g/cm2; P=0.02); lower TBS (1.13 vs. 1.23; P<0.0001) and higher TH sBMD (183.2 vs. 172.4 g/cm2; P=0.05) in comparison to patients in highest quartile (Q4vitD; mean 34.5 nnmol/l). There was no difference in TH BMD, FN BMD, mCth, vBMD, CTx and P1NP between Q1vitD vs. Q4vitD.
Conclusions: This study indicates that in patients with acromegaly low levels of vitamin D may contribute to significant impairment in trabecular bone at lumbar spine, as represented by TBS. Higher sBMD at TH could indicate increased amount of cortical bone caused by GH hypersecretion, but cortical porosity could be decreased, as showed by previous studies with bone biopsies. We recommend maintaining vitamin D levels in sufficient range in all patients with acromegaly.