Leung Vivian W Y, Shalansky Stephen J, Lo Melissa K, Jadusingh Esther A
Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Columbia, Canada.
Ann Pharmacother. 2009 May;43(5):875-81. doi: 10.1345/aph.1L631. Epub 2009 Apr 28.
The use of complementary and alternative medicine (CAM), including orally administered herbals, botanicals, vitamins, and supplements, may pose a risk to patients on warfarin therapy.
To estimate the prevalence of CAM use among patients taking warfarin and evaluate the impact of CAM exposure on the risk of warfarin-related adverse effects.
A survey was administered to hospital inpatients and clinic outpatients on drug exposure (including CAM) over the previous month, self-reported bleeding events, use of alcohol and vitamin K-rich foods, and medical conditions. Prescription medication use was verified, and laboratory records were checked for out-of-range international normalized ratios (INRs) (defined as INR >4 or <2). The use of CAM, including products with reported or theoretical interactions with warfarin, was compared between patients with and without self-reported bleeding or out-of-range INR.
Among the 314 patients who completed the survey, 44.3% reported using CAM at least weekly. Potentially interacting CAM was used by 34.1% of all patients, or 18.2% if vitamin E was excluded as an interacting CAM. Vitamin E was used by 24.2% of all patients and 71.0% of those who used potentially interacting CAM. There was no significant difference in CAM use or consumption of vitamin K-rich foods between patients with and without INRs greater than 4 or for patients with and without INRs less than 2.
The use of potentially interacting CAM in this cohort was higher than the use previously reported among patients on warfarin therapy. However, exposure to CAM was not associated with an increase in the risk of self-reported bleeding or out-of-range INR.
使用补充和替代医学（CAM），包括口服草药、植物药、维生素和补充剂，可能会给接受华法林治疗的患者带来风险。
评估服用华法林的患者中使用CAM的流行率，并评估接触CAM对华法林相关不良反应风险的影响。
对医院住院患者和门诊患者进行一项调查，内容包括过去一个月的药物接触情况（包括CAM）、自我报告的出血事件、酒精和富含维生素K食物的摄入情况以及医疗状况。核实处方药物的使用情况，并检查实验室记录中超出范围的国际标准化比值（INR）（定义为INR>4或<2）。比较有和没有自我报告出血或INR超出范围的患者之间CAM的使用情况，包括与华法林有报告或理论上相互作用的产品。
在完成调查的314名患者中，44.3%报告至少每周使用一次CAM。34.1%的所有患者使用了可能相互作用的CAM，如果将维生素E排除在相互作用的CAM之外，则为18.2%。24.2%的所有患者使用了维生素E，在使用可能相互作用的CAM的患者中这一比例为71.0%。INR大于4的患者与INR不大于4的患者之间，以及INR小于2的患者与INR不小于2的患者之间，CAM的使用情况或富含维生素K食物的摄入量没有显著差异。
该队列中使用可能相互作用的CAM的情况高于先前报道的接受华法林治疗患者中的使用情况。然而，接触CAM与自我报告出血或INR超出范围的风险增加无关。
