Endocrine Abstracts (2017) 49 EP243 | DOI: 10.1530/endoabs.49.EP243

Impact of vitamin D on the bone quality assessed by trabecular bone score in men

Mário Rui Mascarenhas1,2, Ana Paula Barbosa1,2, Nuno Duarte2, Ana Wessling2,3, Ana Raquel Coelho Gomes3, Carolina Faria3, Raquel Paixão3, David Barbosa3, Catarina Silvestre3, José Poupino2, Vânia Gomes3, Ana Sofia Osório3, Francisco Sampaio2, Jacinto Monteiro2, Didier Hans4, Manuel Bicho1 & Maria João Bugalho2,3

1Endocrinology and Metabolic Diseases, Faculty Medicine of Lisbon, Lisbon, Portugal; 2Fracturary Osteoporosis Outpatient Clinic – Endocrinology, Diabetes and Metabolism Department, Santa University Maria Hospital-Chln, Epe, Lisbon, Portugal; 3Endocrinology, Diabetes and Metabolism Department, Santa University Maria Hospital-Chln, Epe, Lisbon, Portugal; 4Bone Center, Lausanne University Hospital, Lausanne, Switzerland.

Trabecular bone score (TBS) is a recent noninvasive analytical method, based upon DXA images, related to bone microarchitecture or bone quality; together, TBS and DXA may evidence bone strength. Falls and osteoporotic fractures increase with ageing, while both BMD and vitamin D levels slowly decline. Data about the influence of vitamin D on the TBS are scarce.

Aim: To evaluate the influence of the blood vitamin D levels on the TBS in normal men.

Material and methods: The lumbar spine BMD (g/cm2), and TBS (obtained from DXA scans) were evaluated in a group of normal men more than 40 years old. Fasting blood was collected for osteocalcin, 25(OH)D and iPTH measurements. This group was divided in normal, insufficiency and deficiency vitamin D groups (ES Guidelines) and also in normal BMD, low BMD and osteoporosis groups. Total body fat and lean masses were also assessed by DXA. Adequate statistical tests were used (statistical significance P<0.05).

Results: The mean (±S.D.) BMD and TBS of the vitamin D groups are shown in Table 1. Men of the deficiency vitamin D group were the heaviest and had the lowest TBS. Significant relations were detected between the blood 25(OH)D vs. TBS, vs. weight and vs. total fat mass but not vs. BMD.

Table 1
Groups VariableNormal (49.3%)Insufficiency (37.7%)Deficiency (13.0%)P
TBS L1-L4 1.044 (±0.14)1.087 (±0.16)1.079(±0.15)0.0071
L1-L4 BMD g/cm21.294 (±0.12)1.323 (±0.12)1.434 (±0.07)NSD

Conclusions: Blood 25(OH)D levels may play an important role on the bone microarchitecture (by TBS) in vitamin D deficient men, as they have worse bone quality. These data suggest that further studies are needed on larger cohort of men and it might be worth to investigate also elderly men with osteomalacia.