Endocrinology and Diabetes, Universitá Campus Bio-Medico di Roma, Via Alvaro del Portillo 21, 00128 Rome, Italy.
Dipartimento di Medicina Interna e Specialistica (DIMIS), Università di Palermo, Via del Vespro 129, 90127 Palermo, Italy.
Int J Endocrinol. 2014;2014:487463. doi: 10.1155/2014/487463. Epub 2014 Jul 7.
It is unclear which vitamin D status is optimal for bone health. In this study, we aimed to assess cutoffs of 25-hydroxyvitamin D (25OHD) derived by the literature (20, 25, or 30 ng/mL) in relation to bone turnover and bone mineral density (BMD). Serum 25OHD, PTH, osteocalcin, bone alkaline phosphatase, and C-telopeptide were measured in 274 consecutive postmenopausal women. BMD of the lumbar spine (L1-L4) and of femoral neck were also evaluated. 50 patients had normal BMD, while 124 had osteopenia and 100 had osteoporosis. 37.6%, 56.2%, and 70.8% subjects had serum 25OHD lower than 20, 25, or 30 ng/mL, respectively. No differences in bone turnover markers were found when comparing patients with low 25OHD defined according to the different cutoffs. However, a cutoff of 25 ng/mL appeared to differentiate better than a cutoff of 30 ng/mL in those subjects with reduced femoral neck BMD. The PTH plateau occurred at 25OHD levels of 26-30 ng/mL. In conclusion, vitamin D deficiency is common in Sicilian postmenopausal women and it may be associated with low BMD and increased bone turnover markers. Further studies are needed to better define the right cutoff for normal vitamin D levels in postmenopausal women.
目前尚不清楚哪种维生素 D 状态最有益于骨骼健康。在这项研究中，我们旨在评估文献中得出的 25-羟维生素 D（25OHD）的切点（20、25 或 30ng/ml）与骨转换和骨密度（BMD）的关系。我们检测了 274 例连续的绝经后妇女的血清 25OHD、甲状旁腺激素（PTH）、骨钙素、碱性磷酸酶和 C 端肽。还评估了腰椎（L1-L4）和股骨颈的 BMD。50 例患者的 BMD 正常，124 例患者患有骨质疏松症，100 例患者患有骨质疏松症。分别有 37.6%、56.2%和 70.8%的患者的血清 25OHD 低于 20、25 或 30ng/ml。根据不同的切点，比较低 25OHD 的患者之间，骨转换标志物无差异。然而，与 30ng/ml 的切点相比，25ng/ml 的切点似乎更能区分那些股骨颈 BMD 降低的患者。当 25OHD 水平在 26-30ng/ml 之间时，PTH 平台出现。总之，西西里绝经后妇女维生素 D 缺乏很常见，可能与低 BMD 和增加的骨转换标志物有关。需要进一步的研究来更好地定义绝经后妇女正常维生素 D 水平的正确切点。
