Department of Endocrinology and Internal Medicine, Aarhus University Hospital, Tage-Hansens Gade 2, 8000, Aarhus C, Denmark.
Department of Clinical Medicine, Aarhus University, Palle Juul-Jensens Boulevard 82, 8200, Aarhus N, Denmark.
Osteoporos Int. 2018 Oct;29(10):2211-2218. doi: 10.1007/s00198-018-4602-x. Epub 2018 Jun 28.
Increased levels of parathyroid hormone (PTH) may have adverse effects on bone health. In a cross-sectional design, we investigated this hypothesis among 102 postmenopausal vitamin D insufficient women. Elevated PTH was associated with altered bone geometry, decreased bone mineral density in the spine, and increased bone turnover.
In vitamin D insufficiency, elevated parathyroid hormone (PTH) levels may contribute to adverse effect on bone. We assessed effects of PTH responses to vitamin D insufficiency on bone metabolism, density, and geometry.
Using a cross-sectional design, we investigated 102 healthy postmenopausal women with low 25-hydroxy-vitamin D (< 50 nmol/L) levels, who had either secondary hyperparathyroidism with elevated PTH levels (> 6.9 pmol/L, N = 51) or normal PTH levels (N = 51). Bone mineral density (BMD) and bone geometry were assessed by Dual-Energy X-ray absorptiometry (DXA), quantitative computed tomography (QCT) and high-resolution peripheral QCT (HRpQCT) scans. Bone metabolism was assessed by biochemistry including bone turnover markers.
Levels of 25(OH)D were 38 (IQR 31-45) nmol/L with no differences between groups. PTH levels were 8.5 (IQR 7.5-9.5) in women with SHPT and 5.2 (4.4-6.6) pmol/L in women with normal PTH (p < 0.001). BMI and eGFR did not differ between groups. SHPT was associated with lower total- and trabecular bone area, lower cortical perimeter, and increased cortical area in tibia and radius. SHPT was associated with a lower weight-adjusted BMD at the lumbar spine (p < 0.05). High compared to normal PTH levels were associated with significantly lower plasma levels of 1,25(OH)D, phosphate, but higher levels of osteocalcin and borderline higher levels of CTx. PTH correlated to osteocalcin and CTx.
High PTH levels are associated with altered bone geometry, increased bone turnover, and reduced BMD at the spine. Whether an increased cortical thickness with a lower trabecular volume is an effect of PTH or not needs further elucidations.
在维生素 D 不足的情况下，甲状旁腺激素 (PTH) 水平升高可能对骨骼健康产生不利影响。我们评估了维生素 D 不足时 PTH 反应对骨代谢、密度和几何结构的影响。
采用横断面设计，我们研究了 102 名绝经后低 25-羟维生素 D(<50nmol/L)水平的健康女性，她们要么甲状旁腺激素水平升高(>6.9pmol/L，N=51)，要么甲状旁腺激素水平正常(51 名)。通过双能 X 射线吸收法(DXA)、定量计算机断层扫描(QCT)和高分辨率外周 QCT(HRpQCT)扫描评估骨矿物质密度(BMD)和骨几何结构。通过生物化学包括骨转换标志物评估骨代谢。
25(OH)D 水平为 38(nmol/L) (IQR 31-45)，两组间无差异。SHPT 组 PTH 水平为 8.5(IQR 7.5-9.5)，正常 PTH 组为 5.2(4.4-6.6) pmol/L(p<0.001)。两组 BMI 和 eGFR 无差异。SHPT 与总骨和小梁骨面积降低、皮质周长降低、胫骨和桡骨皮质面积增加有关。SHPT 与腰椎负重调整后的 BMD 降低有关(p<0.05)。与正常 PTH 水平相比，高 PTH 水平与血浆 1,25(OH)D、磷酸盐水平显著降低有关，但与骨钙素水平升高和 CTx 水平升高有关。PTH 与骨钙素和 CTx 相关。
高 PTH 水平与骨几何结构改变、骨转换增加和脊柱 BMD 降低有关。较高的皮质厚度和较低的小梁体积是 PTH 的作用，还是其他因素的作用，尚需进一步阐明。
