Zuchinali P, Souza G C, de Assis M C S, Rabelo E R, Rohde L E
Medical School, Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
Nutr Hosp. 2012 Nov-Dec;27(6):1987-92. doi: 10.3305/nh.2012.27.6.6068.
Dietary vitamin K intake has been considered a major factor that influences stability of oral anticoagulation (OA) with coumarins. Few studies have evaluated the relationship between amounts of dietary vitamin K intake and stability of anticoagulation.
To assess whether high dietary vitamin K intake is associated to stability of International Normalized Ratio (INR) of the prothrombin time.
We performed a sub-analysis of a randomized clinical trial involving outpatients from the anticoagulation clinic of a university hospital. INR and vitamin K intake were prospectively collected at baseline, 15, 30, 60 and 90 days after randomization. Patients were considered with a stable anticoagulation when their INR coefficient of variation was less than 10%. Dietary vitamin K intake was assessed by a food frequency questionnair and a score of intake was derived.
We studied 132 patients on chronic OA (57 ± 13 years; 55% males); 23 patients (17%) were achieved stable anticoagulation. Stable and unstable patients had no significant differences in baseline characteristics. The dietary vitamin K score over the entire follow-up for stable patients was significantly lower than that for unstable patients (p = 0.012).
Our findings suggest that INR stability could be achieved with relatively low amounts of dietary vitamin K.
膳食维生素K摄入量一直被认为是影响香豆素类口服抗凝治疗(OA)稳定性的主要因素。很少有研究评估膳食维生素K摄入量与抗凝稳定性之间的关系。
评估高膳食维生素K摄入量是否与凝血酶原时间国际标准化比值(INR)的稳定性相关。
我们对一项涉及大学医院抗凝门诊门诊患者的随机临床试验进行了亚分析。在随机分组后的基线、15、30、60和90天前瞻性收集INR和维生素K摄入量。当患者的INR变异系数小于10%时,认为其抗凝稳定。通过食物频率问卷评估膳食维生素K摄入量,并得出摄入量评分。
我们研究了132例接受慢性OA治疗的患者(57±13岁;55%为男性);23例患者(17%)实现了稳定抗凝。稳定组和不稳定组患者的基线特征无显著差异。稳定患者在整个随访期间的膳食维生素K评分显著低于不稳定患者(p = 0.012)。
我们的研究结果表明,相对较低的膳食维生素K摄入量即可实现INR稳定。