维他命D值低会促成压力型骨折风险


  【24drs.com】根据发表于二月号足踝外科期刊的一篇回溯世代研究,至少有半数压力型骨折患者的维他命D值不足。
  
  第一作者、宾州马尔文Premier骨科与运动医学的Jason R Miller医师等人写道,一个人的维他命D浓度,与饮食钙及磷的摄取密切相关。
  
  他们指出,维他命D缺乏者仅吸收约10%至15%的饮食钙质和50%至60%的饮食磷,因此,可能会发生骨质降低与结构完整性不足,以及钙数值降低。
  
  不过,作者们表示,他们的研究对象、体适能良好、有运动者中,维他命D不足的阈值各异;对于功能需求增加者,无法定义一个可以保证适当骨骼健康的最低血清25-hydroxyvitamin D [25(OH)D]值。
  
  我们希望,多多讨论「对于可能有压力型骨折风险的活动型患者,建议维持比较高之正常血清维他命D值」的可能性。
  
  相对于常见的运动伤害,压力型骨折发生于施诸骨骼的压力超过它承受这些压力的能力时。
  
  研究者回溯回顾了2011年7月至2014年8月间在Miller医师的诊所确认有压力型骨折之患者的病历,独立审查确认有压力型骨折诊断的124名患者的X光片和/或磁振造影资料。
  
  有53名患者在他们的骨折诊断前3个月内有测量维他命D值,平均血清25(OH)D值为31.1 ng/mL,其中,44名患者(83%)的数值低于40 ng/mL,根据维他命D委员会的标准认定为不足。约半数、28名患者(52.8%)的数值低于30 ng/mL,根据美国内分泌协会的建议认定为不足。
  
  约三分之一(33.9%)患者的第二脚骨(跖骨)有压力型骨折,这是压力型骨折最常见的类型,另17.7%患者在第三跖骨发生。
  
  作者们指出,血清25(OH)D值和发生压力型骨折之间的关联,在之前一些已发表的研究中曾提出,已经进行广泛的研究,在年轻而活跃的新兵中曾有报告。
  
  他们建议,血清维他命D值至少达40 ng/mL,以预防压力型骨折,特别是需要中度或高度功能需求的活动型患者。
  
  因为17%患者的数值至少有40 ng/mL,作者们说明了压力型骨折其它的一些风险因素,如之前定义的,包括白种人、女性、尼古丁与酒精滥用、使用类固醇、骨密度低、身体质量指数低、使用双磷酸盐类药物治疗。
  
  当有维他命D不足或缺乏且发生压力型骨折时,研究者建议,主要可根据内分泌协会维他命D缺乏患者的指引进行补充。
  
  他们写道,对于25(OH)D值<35 ng/mL者,我们会建议高剂量补充,导入4至8周的处方,每周剂量50,000 IU,直到骨折愈合;对于血清浓度35 -40 ng/mL者,我们建议每天3000- 5000 IU。
  
  他们结论指出,维他命D值达到适当程度之后,患者可以服用至少每天2000 IU的维持剂量。
  
  资料来源:http://www.24drs.com/
  
  Native link:Low Vitamin D Levels May Contribute to Stress Fracture Risk

Low Vitamin D Levels May Contribute to Stress Fracture Risk

By Tara Haelle
Medscape Medical News

At least half of patients with stress fractures who had their vitamin D levels tested had insufficient levels, according to a retrospective cohort study published in the January–February issue of the Journal of Foot & Ankle Surgery.

"An individual's vitamin D concentration is intimately linked to the absorption of dietary calcium and phosphorus," write lead author Jason R Miller, DPM, of Premier Orthopedics and Sports Medicine in Malvern, Pennsylvania, and colleagues.

They note that individuals with vitamin D deficiency only absorb approximately 10% to 15% of dietary calcium and 50% to 60% of dietary phosphorus, "thus, a decrease in bone mineralization and structural integrity can develop," with a decrease in calcium levels.

The authors also say, however, that the varying thresholds for vitamin D insufficiency are estimates among the type of patients they studied — fit, active individuals. "No minimum serum 25-hydroxyvitamin D [25(OH)D] level has been defined that can guarantee adequate skeletal health in a patient with an increased functional demand," they note.

Nevertheless, "we wish to encourage a discussion of the possibility that a higher 'norm' concentration of serum vitamin D should be recommended for active patients who may be at risk of stress fractures."

Study Confirms Previous Findings

Stress fractures, a relatively common sports-related injury, occur when stress on a bone exceeds its capacity to withstand those forces.

The researchers retrospectively reviewed the medical records of patients with confirmed stress fractures seen in Dr Miller's practice from July 2011 through August 2014. Independent review of radiographs and/or magnetic resonance imaging confirmed the stress fracture diagnosis in 124 patients.

The 53 patients who had their vitamin D levels measured within 3 months of their fracture diagnosis had an average serum 25(OH)D level of 31.1 ng/mL. Of these, 44 patients (83%) had levels below 40 ng/mL, considered insufficient based on standards of the Vitamin D Council. And about half, 28 patients (52.8%), had levels below 30 ng/mL, considered insufficient based on recommendations by the US Endocrine Society.

About a third (33.9%) of patients had a stress fracture in the second foot bone (metatarsal), the most common bone seen with a stress fracture, and 17.7% had one in the third metatarsal.

"The association between serum 25(OH)D levels and the occurrence of stress fractures has been previously documented in published studies, extensive investigation has been performed, and association has been reported in young and active military recruits," the authors note.

They recommend minimum serum vitamin D levels of at least 40 ng/mL to prevent stress fractures, "especially for active patients with a moderate or high functional demand."

Because 17% of patients had levels of at least 40 ng/mL, the authors describe other risk factors for stress fractures, also previously identified, including white race, female gender, nicotine and alcohol abuse, steroid use, low bone density, low body mass index, and bisphosphonate therapy.

Supplement When Vitamin D Sufficiency Accompanies Stress Fracture

When vitamin D insufficiency or deficiency exists alongside a stress fracture, the researchers recommend supplementation based largely on the Endocrine Society's guidelines for vitamin D deficient patients.

"We would advocate high dosage supplementation for individuals with a 25(OH)D of <35 ng/mL, introducing a 4- to 8-week regimen of a 50,000 IU weekly dose until fracture healing has occurred," they write.

"For those with a serum concentration of 35 to 40 ng/mL, we would recommend 3000 to 5000 IU daily."

After vitamin D levels are adequate, patients can take a maintenance dose of at least 2000 IU daily, they conclude.

No external funding or disclosures were reported.

J Foot Ankle Surg . 2016;55:117-120.

    
相关报导
虚拟切片为即将发生的骨折风险提供处置时机
2016/10/5 下午 03:53:03
维他命D值低与黄斑部病变风险有关
2016/4/21 上午 09:45:19
手术对于减少副甲状腺机能亢进症之骨折效果最佳
2016/4/15 下午 01:13:29

上一页
   1   2   3   4   5   6   7   8   9   10  




回上一页