据7月10日发表在《美国医学会杂志》上的一则研究披露，在一个多族裔的成人组中，白人及华裔参与者的血清25 - 羟维生素D浓度低与冠心病事件风险的增加有关，但在黑人或西语裔中则不存在这种关系；这些结果表明，维生素D补充剂的风险和裨益应该在各种族与族裔中进行仔细的评估。
“大多数的有关25 - 羟维生素D（25[OH] D）与冠心病（CHD）风险的研究所检查的是大体或完全由白人参与者组成的人群。这些研究的结果常常被类推至多种族人群。这样做可能是不恰当的，因为维生素D代谢和循环中的25（OH）D浓度会因为种族/族裔而有很大的差别。”
华盛顿大学西雅图分校的Cassianne Robinson-Cohen, Ph.D.及其同事在一个大型的、基于社区的多族裔成年人群中对血清25(OH)D浓度与事件性CHD发作之间的关系进行了检查。该分析中包括了参与多族裔动脉粥样硬化研究（MESA）的6436位参与者，他们是在2000年7月至2002年9月间被招募的。研究人员检测了基线血清25(OH)D浓度，而25(OH)D与判定的CHD事件的关系的评估一直持续到2012年5月。判定的CHD事件被定义为心肌梗塞（心脏病发作）、心绞痛、心脏骤停，或CHD死亡。
在本研究开始的时候，参与者的平均年龄为62岁，其中53%为妇女。血清25(OH)D平均浓度随着种族/族裔的不同而有相当大的变化。在中位数（中点）为8.5年的随访中，有361位参与者出现过一次CHD事件。
研究人员发现25(OH)D与CHD风险之间的关系会因种族/族裔而存在明显的异质性。在白人参与者中，血清25(OH)D浓度较低与CHD风险的显著增高有关系，25(OH)D浓度每降低10 ng/mL，其风险会增加26%；而在华裔参与者中，其风险会增加67%。“然而，没有证据显示在黑人或西语裔中有这种关系。”
“我们的研究表明，维生素D补充剂的风险和裨益应该在各个种族及族裔中进行仔细评估，而正在进行中的维生素D临床试验的结果应该谨慎地运用于非白人的个体。”（生物谷 Bioon.com）
生物谷推荐的英文摘要
JAMA doi:10.1001/jama.2013.7228
Racial Differences in the Association of Serum 25-Hydroxyvitamin D Concentration With Coronary Heart Disease Events
Cassianne Robinson-Cohen, PhD1; Andrew N. Hoofnagle, MD, PhD2; Joachim H. Ix, MD, MAS3; Michael C. Sachs, PhD1; Russell P. Tracy, PhD4; David S. Siscovick, MD, MPH5; Bryan R. Kestenbaum, MD, MS1,6; Ian H. de Boer, MD, MS1,6
Importance Low circulating concentrations of 25-hydroxyvitamin D (25[OH]D) have been consistently associated with an increased risk of coronary heart disease (CHD) in white populations. This association has not been rigorously evaluated in other races or ethnicities, in which the distributions of 25(OH)D concentration and possibly other aspects of 25(OH)D metabolism differ.
Objective To examine the association of serum 25(OH)D concentration with risk of CHD in a multiethnic population.
Design, Setting, and Participants We studied 6436 participants in the Multi-Ethnic Study of Atherosclerosis (MESA), recruited from July 2000 through September 2002, who were free of known cardiovascular disease at baseline. We measured baseline serum 25(OH)D concentrations using a mass spectrometry assay calibrated to established standards. We tested associations of 25(OH)D with adjudicated CHD events assessed through May 2012.
Main Outcome and Measures Primary outcome measure was time to first adjudicated CHD event, defined as myocardial infarction, angina, cardiac arrest, or CHD death.
Results During a median follow-up of 8.5 years, 361 participants had an incident CHD event (7.38 events per 1000 person-years). Associations of 25(OH)D with CHD differed by race/ethnicity (P for interaction < .05). After adjustment, lower 25(OH)D concentration was associated with a greater risk of incident CHD among participants who were white (n = 167 events; hazard ratio [HR], 1.26 [95% CI, 1.06-1.49] for each 10-ng/mL decrement in 25(OH)D) or Chinese (HR, 1.67 [95% CI, 1.07-2.61]; n = 27). In contrast, 25(OH)D was not associated with risk of CHD in participants who were black (HR, 0.93 [95% CI, 0.73-1.20]; n = 94) or Hispanic (HR, 1.01 [95% CI, 0.77-1.33]; n = 73).
Conclusions and Relevance Lower serum 25(OH)D concentration was associated with an increased risk of incident CHD events among participants who were white or Chinese but not black or Hispanic. Results evaluating 25(OH)D in ethnically homogeneous populations may not be broadly generalizable to other racial or ethnic groups.
