Thrailkill Kathryn M, Fowlkes John L
Department of Pediatrics, University of Arkansas for Medical Sciences, Little Rock, AR.
Clin Rev Bone Miner Metab. 2013 Mar 1;11(1):28-37. doi: 10.1007/s12018-012-9127-9.
Most studies across a variety of geographic locations suggest that vitamin D insufficiency is more common in individuals with type 1 diabetes (T1D) compared to the general population. In type 2 diabetes (T2D), while obesity is commonplace and lower vitamin D levels are present in obese adolescents and adults, the association between vitamin D insufficiency and T2D is less clear. Studies suggest that the relationship between T2D and vitamin D may be concurrently influenced by ethnicity, geography, BMI and age. None-the-less, diabetic osteopathy is a significant co-morbidity of both forms of diabetes, and is characterized by micro-architectural changes that decrease bone quality leading to an increased risk for bone fracture in both disorders. The question remains, however, to what degree vitamin D homeostasis contributes to or exacerbates skeletal pathology in diabetes. Proposed mechanisms for vitamin D deficiency in diabetes include: 1) genetic predisposition (T1D); 2) increased BMI (T2D); 3) concurrent albuminuria (T1D or T2D); or 4) exaggerated renal excretion of vitamin D metabolites or vitamin D binding protein (T1D, T2D, animal models). The specific effects of vitamin D treatment on diabetic osteoporosis have been examined in rodents, and demonstrate skeletal improvements even in the face of untreated diabetes. However, human clinical trial data examining whether vitamin D status can be directly related to or is predictive of bone quality and fracture risk in those with diabetes is still needed. Herein, we provide a review of the literature linking vitamin D, diabetes and skeletal health.
来自不同地理位置的大多数研究表明，与普通人群相比，1型糖尿病（T1D）患者中维生素D不足更为常见。在2型糖尿病（T2D）中，虽然肥胖很常见，肥胖青少年和成年人的维生素D水平较低，但维生素D不足与T2D之间的关联尚不清楚。研究表明，T2D与维生素D之间的关系可能同时受到种族、地理位置、体重指数（BMI）和年龄的影响。尽管如此，糖尿病性骨病是两种糖尿病的一种重要合并症，其特征是微观结构变化，导致骨质下降，从而增加了这两种疾病中骨折的风险。然而，问题仍然存在，即维生素D稳态在多大程度上导致或加剧了糖尿病中的骨骼病变。糖尿病中维生素D缺乏的可能机制包括：1）遗传易感性（T1D）；2）BMI增加（T2D）；3）并发白蛋白尿（T1D或T2D）；或4）维生素D代谢产物或维生素D结合蛋白的肾脏排泄增加（T1D、T2D、动物模型）。维生素D治疗对糖尿病性骨质疏松症的具体影响已在啮齿动物中进行了研究，结果表明，即使在未治疗糖尿病的情况下，骨骼状况也有所改善。然而，仍需要人体临床试验数据来检验维生素D状态是否与糖尿病患者的骨质量和骨折风险直接相关或具有预测性。在此，我们对有关维生素D、糖尿病和骨骼健康的文献进行综述。
