Instituto de Biomedicina de Sevilla, IBIS (Universidad de Sevilla, HUVR, Junta de Andalucía, CSIC), Sevilla, Spain.
Department of Clinical Biochemistry, Virgen del Rocío University Hospital, Seville, Spain.
Exp Gerontol. 2018 Jul 15;108:201-208. doi: 10.1016/j.exger.2018.04.019. Epub 2018 Apr 26.
Homocysteine (Hcy) high levels are associated with fractures, bone resorption and an early onset of osteoporosis in elderly persons; a relationship between Hcy and bone formation has also been suggested but is still controversial. Frailty, an independent predictor of fractures and decreased bone mineral density is associated with altered bone metabolism in women. However, no previous works have studied the relationship among frailty, Hcy levels and bone turnover.
We studied the association among Hcy, osteoporosis and N-terminal propeptide of type I procollagen (PINP), C-terminal telopeptide of type I collagen (β-CTX), parathyroid hormone (PTH), calcium and 25-hydroxyvitamin D (25(OH)D) in 631 Spanish women between the ages of 65-78 from the Toledo Study for Healthy Aging (TSHA) cohort, who were classified as highly functional (robust subjects) or non-robust (pre-frail or frail subjects) according to Fried's criteria.
Hcy was independently associated with β-CTX in the entire population (B = 0.22; 95% CI, 0.09-0.34; p = 0.001) and in the non-robust group (B = 0.24; 95% CI, 0.09-0.39; p = 0.002). Hcy was also associated with PINP in the entire and non-robust populations, but the association was lost after including the levels of β-CTX, but not the other bone biomarkers, in the multivariate analysis. This suggests that the controversial relationship between Hcy and bone formation might be explained, at least to a certain extent, by the confounding effects of β-CTX.
This work highlights the important implication of frailty status in the association between Hcy and increased bone turnover in older women.
同型半胱氨酸（Hcy）水平升高与老年人骨折、骨吸收和骨质疏松症的早期发生有关；也有人提出 Hcy 与骨形成之间存在关系，但仍存在争议。衰弱是骨折和骨密度降低的独立预测因素，与女性骨代谢改变有关。然而，以前没有研究过衰弱、Hcy 水平和骨转换之间的关系。
我们研究了 631 名年龄在 65-78 岁的西班牙女性（来自托莱多健康老龄化研究（TSHA）队列）中 Hcy、骨质疏松症和 I 型前胶原 N 端前肽（PINP）、I 型胶原 C 端肽（β-CTX）、甲状旁腺激素（PTH）、钙和 25-羟维生素 D（25(OH)D）之间的关系，这些女性根据 Fried 的标准分为功能高度正常（健壮受试者）或非健壮（衰弱前期或衰弱受试者）。
Hcy 与整个人群中的β-CTX 独立相关（B=0.22；95%CI，0.09-0.34；p=0.001）和非健壮组（B=0.24；95%CI，0.09-0.39；p=0.002）。Hcy 与整个和非健壮人群中的 PINP 也相关，但在多元分析中纳入β-CTX 水平后，这种相关性消失，但不包括其他骨生物标志物。这表明，Hcy 与骨形成之间有争议的关系可能至少在一定程度上可以用β-CTX 的混杂作用来解释。
这项工作强调了衰弱状态在老年女性中 Hcy 与骨转换增加之间的关联中的重要意义。
