Ahn Seong Hee, Lee Seokhyeon, Kim Hyeonmok, Lee Seung Hun, Kim Beom-Jun, Koh Jung-Min
a Department of Endocrinology , Inha University School of Medicine , Incheon , Republic of Korea.
b Division of Endocrinology and Metabolism , Asan Medical Center, University of Ulsan College of Medicine , Seoul , Republic of Korea.
Endocr Res. 2016 Nov;41(4):334-342. doi: 10.3109/07435800.2016.1155600. Epub 2016 Apr 4.
Despite the clear effect of iron on bone metabolism, most clinical studies related to bone health have only focused on bone mineral density (BMD). In the present study, we investigated the relationship between serum ferritin and composite indices of femur neck strength via a population-based, cross-sectional study using the Korea National Health and Nutrition Examination Survey (KNHANES).
Our study series included 693 women at the stage of bone loss (≥ 45 years of age), defined based on the observed patterns of age-related BMD changes in the KNHANES. Geometric bone structure properties, including hip axis length (HAL) and femur neck width (FNW), were measured using hip dual-energy X-ray absorptiometry scans and were combined with BMD, body weight, and height to create composite indices of femur neck strength relative to load in three different failure modes: compression (CSI), bending (BSI), and impact strength indices (ISI).
After adjustment for age, body mass index (BMI), lifestyle factors, serum 25-hydroxyvitamin D, calcium and phosphorus intake, diabetes, and menopause status, multiple regression analyses revealed that serum ferritin was inversely associated with the BMD values at the lumbar spine and femur neck, and the femur neck cortical thickness. Importantly, in all adjustment models, higher serum ferritin was consistently associated with the lower values for all three femur neck composite indices, such as CSI, BSI, and ISI.
These data provide the first clinical evidence that increased total body iron stores reflected by higher serum ferritin may be associated with the decrease of bone strength relative to load.
尽管铁对骨代谢有明确影响，但大多数与骨骼健康相关的临床研究仅关注骨矿物质密度（BMD）。在本研究中，我们通过一项基于韩国国家健康与营养检查调查（KNHANES）的人群横断面研究，调查了血清铁蛋白与股骨颈强度复合指标之间的关系。
我们的研究系列包括693名处于骨质流失阶段（≥45岁）的女性，这是根据KNHANES中观察到的与年龄相关的BMD变化模式定义的。使用髋部双能X线吸收法扫描测量包括髋轴长度（HAL）和股骨颈宽度（FNW）在内的几何骨结构特性，并将其与BMD、体重和身高相结合，以创建相对于三种不同失效模式（压缩（CSI）、弯曲（BSI）和冲击强度指数（ISI））负荷的股骨颈强度复合指标。
在对年龄、体重指数（BMI）、生活方式因素、血清25-羟基维生素D、钙和磷摄入量、糖尿病和绝经状态进行调整后，多元回归分析显示血清铁蛋白与腰椎和股骨颈的BMD值以及股骨颈皮质厚度呈负相关。重要的是，在所有调整模型中，较高的血清铁蛋白始终与所有三个股骨颈复合指标（如CSI、BSI和ISI）的较低值相关。
这些数据提供了首个临床证据表明，较高血清铁蛋白反映出的全身铁储存增加可能与相对于负荷的骨强度降低有关。
